1089

ABSTRACTS FROM AOCS JOURNALS

Correlating VI.sco!iily wilh Temperature and Other Pmperfjes. CharlesH. Fisher. Chemistry Department. Roanoke College. Salem. Virginia24153.

Simple viscosity equations based on Hnearities 111'le (01' ~e) vs. T:T/r[e V5. T and ~ vs. P: ('1. viscosity;~. fluidity: T. temperature; and P.any property 01' property function linear with T. such as. density. refractiv-ity. and surface tension )J are given fOl' glycerol. uiglycerides. glycerideoils. fl-fllUy acids. esters. an alcohol. and an amine.JAOCS ts. 1229--1232 (1998).

SurfKe Tensioft or Prole!n and Insoluble Lipids at the Air-AqueousPhast Inlerface, Ma Rosario Rodriguez Nii\o and Juan M. RodriguezPalino-, Departlllmnto de Ingenieria Quimica. Facultad de Qulmica.Uni~id3d de Sevilla. 41012-Sevilla. Spain.

The surface activity of bovine serum albumin (BSA) in water andIIqlle()tlS solutions of ethanol (0.5, 1.0, and 2.0 M) and SIICI'O§e (0.5 and1.0 M) has been investigated over a range of protein concentrations(5_1.10-5, 'I> w/w). The surface tension data were determined by theWilhelmy plate method. Surface data at low protein concentrations indi-cate a low surface activity, which rises to a plateau as the monolayer issaturated at higher protein concentratioru;. TI!e protein concentration andsurface tension at the plateau depend on the aqueous phase composition.The effect of aqueous phase composition on BSA-lipid interactions hasbeen investigated by spreading an insoluble lipid (monostearin ormonoolein) on II film of BSA previously adsorbed on the interfece. Theexistence of protein-lipid interactions depends on the proteinl1ipid ratio,The surface acnvny of mixed BSA-lipid films is determined by the lipidbecause the surface pressure of the mixed film is the same as the lipidequilibrium spreading pressure, and the monolayer is not saturated byBSA. However, the surface octivity of mixed BSA-lipid films is deter-mined by BSA as the monolayer is saturated by the protein.JADCS 75. 1233-1239 (1998).

Surfllce Tension or Rovlne Serum Albumin and Tween 20 at IheAir-Aqueous Interface. Ma Rosario Rodriguez Nii\o and J.M. RodrfguezPatino", Departamento de lngenierfa Qufmica. Facultad de Qulmica.Universidad de Sevilla. 41012-Sevilla. Spain.

Interfacial properties (surface tension. c. and critical micelle concen-tration. CMC) of aqueous solutions of Tween 20 (polycxyethylene sorbi-tan monolaunue) and/or bovine serum albumin (BSA) were evaluated.Temperature. Tween 20 concentration in the aqueous phase, BSAfTWcen20 ratio. and aqueous pllase composition [water. ethanol (0.5, 1.0. and 2.5M), and SllCl"05C (0.5 M») were the variables studied. llIe CMC of Tween20 was determined by surface tension measurements (Wilhelmy platemethod). Tbe existence of BSA-1'ween 20 inte ....lCtions was deduced fromsurface tension measurements. TI!e results show that the effect of temper-ature on CMC depends on the aqueous phase composition. but the a valueat CMC, 0CMC' does decrease as temperaturc is increased. The CMCand 0CMC values also depend on the aqueous phase composition. Inaqueous ethanol solutions. the CMC increases. but aCMC decreases.However. in sucrose aqueous solutions. the CMC decreases. but there isno significant effect on 0CMe- The BSA- Tween 20 interactions at theinterface depend on both Tween 20 concemrt a tion (C) and solute in thebulk phase. In water and aqueous solutions of ethanol and sucrose. 0 val-ues decrease in the presence of protein at C < CMC but are practicallyindependent of C at C > CMC. This is an indication that the interfacialcharacteristics of the mixed film are determined by either the protein orthe lipid al the higher and [ower protcinl1ipid ratio. respectively. In theintermediate region. thoeexistence of BSA- Tween 20 interactions domi-nates the interfocial characteristics of milted films.JADCS 75.1241-1248 (1998).

A Compllrlson or Physical lind Chemical Propertit's or Milk FalFl1IIclions Obtained by n-·o Processing Technol~es. A.R, Bhaskar",S.S.H. Rizvia,-. C. Bertolib. L.B. Fayh. and B. Hug". Qlru;tirute of FoodScience. Cornell University. Ithaca. New York 14853. and bNestltResearch Centre, 1000 Lausanne 26. Switzerland.

Milk fat fractions from supercritical carbon dioltide (SC-eov CJttrac-

lion were compared with commercial melt crystallization (MC) fractionsfor their physical and chemical properties. The fractions were analyzedfor fatly acids, trincylglycerols. cholesterol. total carotenoid content. andvolatile compounds. Tbe fractions were also evaluated for solid fat con-tent (SFC) by pulsed nuclear magnetic resonance and thermal profiles bydifferential scanning calorimeter (DSC). The distribution of fatly acidsand trlocylglycerols in the fractions depended on the fractionation tech-nique used. SC~ separated fractions based on molecular weight ratherthan on Imlting point. which is the driving force for the MC process. "Thediffercnces among the fractions were quantified from their SFC and DSCcurves. Triacylglycerol profiles by high·performance liquid chromalogra-p/ly showed that the SC~ fractions were distinctly different from eachother and from MC fractions. The SC-C~ solid fraction (super stearin)was the IfIQSI unique. It had. high concentration of joeg-chain. unsatunll-cd fatty acid-containing triacylglycerols in a narrow range of high rnolec-ular weight. indicating a homogeneity of this fraction thal has not: bce:nattainable by other I«hniqUC!S. It was also enriched in P-<arotene and wasdevoid of volatile compounds. As compared to liquid MC fractioru;. theliquid SC-CO:z fraction had a high concentration of low-melting uiacyl-glycerols and was enriched in volatile compoonds. With SC-C02' it isthus possible to simultaneously fractionate and produce a fla\'or-rich coo-centrate at 00 Utnl processing costJAOCS 75.1249-1264 (1998).

'Ow Innuence or Chftnkal IntertSterirlCatlon on Ph)'sicochemic:al Prop-erties or Compltx .'11 Systems I. Melting and CI"}·stallization. AlejandroG. Marangoni- and D!!rid Rousseau. Department of Food Science.University of Guelph. Guelph NIG 2Wl. Ontario. Canada.

The effects of blending palm oil (PO) with soybean oil (S80) and lardwith canola oil. and subsequent chemical intere.sterification (CIE). ontheir melting and crystallization behavior were investigated. Lard under-went larger CIE-induced changes in rriacylglycerot (TAG) compositionthan palm oil. Within 30 min 10 1 h of CIE. changes in TAG profileappeared complete for both lard and PO. PO had a solid rat content (SFC)of -68'1> pt O°C, which diminished by -30% between 10 and 20"C.Dilution with SBO gradually lowered the initial SFC. CIE linearized themelting profile of all palm oil-soybean oil (POSBO) blends between 5and 40·C. Lord SFC followed an entirely different trend. The meltingbehavior of lard and tard-cancla oil (LCO) blends in the 0-4Q'C rangewas linear. CIE led to II"IOI"e abrupt Imlting for all LCD blends. Both sys-terns displayed mcncecuc behavior. ClE increased the DP of POSBOblends with 280'1> PO in the blend and lowered that of blends with :S70'1>PO. All CIE LCO blends had a slightly lower DP ";s-ii-\';s their noninter-esterified counterparts.JADCS 75. 1265-1271 (1998).

Isothermal Crystallizalion or lIydro~enated Sunflower 011:I-Nucleation. M.L. Herrerna,-, C. Falabelta . M. Melgarejo". and M.C.AMna. "Centro de lnvesrigacion y Desarrollo en Cnorecnotogra deAHmentos (CIDCA) (UNLP - CONICET). La Plata 1900. Provincia deBuenos Aires. Argentina, and "Molinos Rfo de La Plata S.A .. BuenosAires 1323. Argentina.

Nucleation kinetics of sunflower seed oil. which was hydrogenatedunder tWOdifferent conditions. was studied by means of a polarized lightmicroscope and an optical setup with a laser as the light source. When thelaser WIISused. observed inductioo times were shorter than the ones mea-sured by the microscope. Tbe laser method was found 10 be more sensitiveand accurate. 1'wo diffcrcnt crystallization behaviors were found dependingon the chemical composition of the samples. Samples with high content oftrielaidin crystallized in the ~ form 01 temperatures close to the meltingpoints. They eXhibited both P' and ~ forms depending on crystallization tem-perature. lIS happens in Mtural semisolid fats such as palm oil. Samples withhigh content of mixed oleic and elaidic teiecylglycerols crystallized in the Wform even III ieniperarures close to the melting points and they did not show~ form under the conditions used in this study. Activation free energies ofnucleation for hydrogenated sunflower seed oil were low for the two hydro-genation conditions. It can be concluded that nucleation of sunflower seedoil is a f!lSl process and initially needs low supercooling. These results an:also important from a practicaJ point of view for processing design. especial-ly in rcgards \0 processc:s in which fats shoukI be completely crystallized bythe end ofthc production line.JAOCS 75.1273-1280(1998).

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Chf'mkal ComposlUon or Commercial Cornlcabra Virgin Ottve Oilfrom 1995196 and 1996/97 Crop:5. M.D. Satvador'", F. Aranda. and G.Fregapane, Univcrsidad de Castilla-La Mancha. Facultad de CiendasQufmicas, Departamento de Qufmici Analltica y Tecno1ogfa deAlimenl05. 13071 Ciudad Real. Spain.

The chemical composition of commercial Comicabra virgin olive oils(II • 65) was studied. as was ns relationship with oil quality and the influ-erce of the elll1llCl.ionmethod and production year. "The main chanJcteris..ties of these olive oils wac: oxidative stability 53 1 24 h. mean poIypheoolCOIltent 162:t,7 mglkg (as gallic acid). oleic acid 8O.8:t 0.9%, linoleic acid4.6:t 0.6%. and campeMeml4.J :to.I<I., which is p.o.culiat to this variety. Noclear differences in composition were observed with respect 10 the differ-ent exll1lClion systems (dual-phaseltriple-pha.se decanters and pressure).although oils produced by the duaJ-pha.se decanter showed higher Ollida-live slDbilily and polyphenol content. lllere were significant diffm:nces inmajor Iauy acids and sterols aa:ording to the prodoction Yea(.JAOCS 75. 130~1311 (1998).

ABSTRACTS FROM AOCS JOURNALS

Determination of Pho!ipholipids in VegetalHe Oil by Fooner TransformInfrared Spedllll'iCOpy, 1.M. Nzai· and A. Proctor. Oepanmcnt of FoodScience. University of Arkansas. Fayetteville. Arkansas 72704.

A method was developed to determine the tOlai phospholipid contentin vegetable oil by Fourier transform infrared spectroscopy (FTIR).Calibration curves of l-e-phosphatidylchollne (PC). t-c-phcs-phatidylethanolamine (PE), and l-c-pbospbatidyhnositcl (PI) in hexanewere generated at different concentrations. The optimal phospholipidabsorplion bands between 1200-970 cm-! were identified and used forquantitative determilUltion. High R2 ~ 0.968 were observed between bandareas and phospholipid standard concentmions. Phospholipids from crude:soybean oil were obtained by water degumming, and purification was per-formed on a silicic acid column. The phospholipid contents of purifiedphospholipid extract. degummed and crude soybean oil determined fromcalibration equations were >90, 0.0113. and 1.77%_ respectively. Highcorrelations of determination (R2 ~ 0.933) were observed between tileFTIR method and thin-layer chromatography-imaging densitometrymethod fOl'the determination of phospholipid contera. FnR was found tobe a useful analytical tool fOf simple and rapid quantitative detenninationof phospholipids in vegetable oil.JAOCS 75.1281-1289 (l998).

Total .'ally Acid AnalJsis or \'egetalHe Oil Soapslocks by SupercriticalFluid Extl'1lctiolV'Reactlon. Jerry W. King·. Scott L. Taylor. Janet M.Snyder, and Russell L. Holliday, Food Qualily and Safety Research,NCAUR. ARS. USDA. Peoria.litinois61604.

Scepstocc from vegetable oil refining operations is a value-added by-product that finds further industrial use based on its Iany acid content.Since the Iauy acid content of 5Oapstock can vary according to its veg-etable oil soun:e or method of refining. determination of its total fatty acid(TFA) by an accurate analytical method is of key importance to pur-chasers of this refinery by-product. Traditionally. the TFA content ofsoapstcck has been determined by the AOCS Official Method 03-53based on a gravimetric assay. Unfcnunately, this gravimetric-based assayrequires considerable time and incorporates a considerable quantity oforganic solvent per assay. In this study. the authors have applied supercrit-ical fluid extraction (SFE) with an enzymatic-based reaction (SFR). in thepresence of supercritical carbon dio~ide (SC-CO:!). to determine the TFAcontent of soaostocks. The SFElSFR sequence was conducted using twocommercially available extractors using an in situ supported lipase in theextraction cell \0 form fally acid methyl esters (FAME). Gas chromato-graphic (GC) determination of the individual FAME, followed by quanti-tetion based on the calculated sum of enme fatty acids from the GC anal-ysis, allowed a precise determination \0 be made of the soapsrock's TFAcontent. The TFA contents of three different soepstocks determined bythis method were slightly higher than the values derived from OfficialMethod 03-53. The reponed method takes less than one-half of the timeof Official Method 03-53 and reduces organic solvent use from 575 mLto under 2 mL of solvent by using SC-C02'JAOeS 75. 1291-1295 (1998).

Characterization or Fatly Acid Isomers in Dehydl'1lted Castor 011 byGas Chromatography and Gas Chromatography-Mass SpectrometryTechniques. Suresh Ramamunhte, Venkat Manohar, and V.V.S. Mani,Hindustan Lever Research Centre. Andheri (East). Mumbai 400099.India.

Feuy acid isomers present in dehydrated castor oil were analyzed by8as chromatography and gas chromatography-mass spectrometry(GC-MS) of their dimethyl oxazonne derivatives. Conjugated linoleicacid 9.11 and 10.12 isomers were identified by GC based on equivalentchainlengths. Segmental peak analysis of GC-MS total ion chromatogrammass fragmentation pattern revealed the presence of 7.9 and 8.10 conju-gated linoleic acids along with 9.11 and 10.12 conjugated linoleic acids.Interestingly. a reverse elution of Irans,IMns-conjugate<! linoleic acidswas observed. ~iz. 10.12 was followed by 9.11 ..... hich was in tum fol-lowed by the 8, I0 and 7,9 isomers. The observed reverse order of elutionwas in COIltraSlto the conventional elution paltern of 00lh nonronjU88tedand conjugated cis.cis-. cis.rrons- and trons.cis-isomers.JAQCS 75,1297-1303 (1998).

Autoxidation or the Funn Fatty Acid Esler, Methyl 9,12..:pox}·oc!adeca-9,1I-dJ.e00llIr. N. $clull, M.P. Yurawecz-. J.A.O. Roach.M.M. Mossoba. K. wliIZ. E.P. Mazzola. and Y. Ku. U.S. Food and DrugAdministration. Center for Food Safety and Applied Nutrition,Washinglon. OC 202Q4.

The objective of this study was to identify autoxidation products ofmethyI9.12-epollyoctadeca·9.1I·dienoate (F9.12)' Previous work hasshown that F9.12 is a product botb of autoxidation and singlet oxygenoxidation of the methyl ester derivative of conjugated linoleic acid (CLA).F9.12' 95'1> pure. was syntbesized from methyl ricinoleate. lbe synthelicF9.12 was heated at 5O"C in scaled tubes containing air. Each tube con-tained 6 mg F9 12 and I mg methyl stearate as an internal standard.Samples were tiken at 4.5, 7, 23, 46.5. 69.5. and 93 h. The oxidized F9.12was dissolved in tscocene and analyzed by gas chromatography (OC).GC-tlirect deposhlcn-Pourler transform infrared spectroscopy. and GC-electron ionization mass spectrometry. CLA methyl ester was oxidized ina similar manner. Under these conditions. the half-lives of CLA and F9,12were 40 lind 35 h, respectively. Oxidation products of F9.12 that wereidentified included: 5·hexyl-2-furaldehyde (I). methyl a-oxccccmcere(II), methyl 13-oxo-9.12-cpoxytrideca·9.II·dienoate (Ill). methyl g-oxo-9.12-epo~y-9.1 I-ocradecedtencere (IV), and methyl 13-o~0-9.12-epoxy-9.II-octadccpdienoate (V).JAOeS75.1313-1319(1998).

Concerns for the Detl'TllIinalion of .'I'I,.-e .'ally Acid In Cottonseed, P.J.Wanll.-. D.R. Pakartnen". and P.J. Wakelynh. aUSDA. ARS. SouthernRegional Re."Ilareh Center. New Orleans. Louisiana 70124, and hN3IionalCOMn Council. Washington. DC 20036.

The official AOCS method for the determination of free rany acid(FFA) in ceuonseed requires dehulllng the seed. grinding the meats with a12-blade food processor. lind extrecting the ground meats in a butt tubewith three portions of recm-temperuture petroleum ether. The extractedoil. after cesolvenuaenon, is then titrated with NaOH to the end point ofphenolphthalein in a mind solvent of isopropanol and hexane. Our studyshowed that this procedu1l: tends to underestimate the amount of FFA pre-sent in the oil of couonseed by as much as II.5'1>. It was also found that10 obtain consistent ond lIC(:urate FFA content. a desirable panicle size issmaller than 10 mesh (preferably <14 mesh). minimum extraction temper-ature should be no less than ~C (preferably greater than 50°C). and theeXlBCtion time should be longer than 2 h in a Soxhlet extractor.JAOeS 75. 1321-1324 (1998).

0cr01'l't'1lCe or 5a...(;hoIesta·7.l4-dlen,~ and 2J..DebJdmlop~noI Inthe Bean Lipids or Vllnillll mlldagllscllrirnsis, Beatrice Ramarcscn-Raoniufinimanana. Emile M. Gaydcu'", and Isabelle Bombarda.Laboratoire de Phytochimie de Marseille. Facult<!! des Sciences etTechniques de Saint HrOme, Universit<!! d'Ailt-Marsci1le Ill. 13397MlITKilIe Cedc:lt 20. Fnmce.

Eleven 4-d.esmethylsterols. four 4.4-dimethylsterols, and twelve 4_methylstcrols were identified in llinilla moJagascariensis beans. The 4_desmethylslerol fTllClionwas ch:uaclCriud by I high level of .5a-cholC$l8-7,24(25}dien-31H>1 (35.3'lb). The 4-methylslCrol fraction was character-ized by I high level of 31-non::yeloanenol (57.5%) and the presence of23-dehydrolophenol (9.4'lb). Cydoartenol (72.~). cyclosadol (12.7'1»,

INFORM. VOl. 9. no. 11 (November 1998)

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parkecl (9.7%), and 24-dchydrotirucallol (4.7~) were identified in the4,4-dimethylstcrol fraction.JAOCS 75, 1325---1328 (1998).

Synlhesls or Polyunsaturated Falty Acid-Enriched Tr\glycerldes bylJpa.'ie-Clilalyud EsterifICation, L. Esteban Ccniin, A. Robles Medina·.A. Gim~nez Gimenez, M.J. Ib'ilez Gondlez. and E. Molina Grima.Departamento de Ingenierfa Qufmica, Universidad de Almerfa. E-04071Almeria, Spain.

This paper reports on the synthesis of triglycerides by enzymaticesterification of potyuesaueated fany adds (PUFA) with glycerol. APUFA concentrate oblained from cod liver oil was used 10 opdrnize thereaction 10 favor triglyceride synthesis with hpeses. The type and amountof lipase and o.ganic solvent. glycerol content. tempcrntun:. water con-lent. and amount and time of addition of molecular sieves were studied.The optimal reaction mixture and conditions were: 9 mL hexane. 6O"C,0.5% (voVvol) water. 1 g molecular sieves added after 24 h of reaction,glyceroVfatly acid molar ratio 1:3 and 100 mg of Novozym 435 (NovoNordisk AlS) lipase. Under these conditions, an enriched triglycerideyield of 84.7% containing 27.4% etccsapemeeeotc acid and 45.1 %docosahexlICnoic acid was obtained from a cod liver oil PUFA ccncen-trate.JAOCS n 1329-1337 (1998).

Enr;ymlltK: Inleresterification or Lard lind High·OleK: Sunno ...er 011with Condida antarctial Lipase to ProdUtt Plastk Fats, Vimon Seriburilind Casimir C. Akoh·. Department of Food Science and Technology.Food Science Building. The University of Georgia. Athens. Georgia30602·7610 ..

Lard lind high-oleic sunflower oil (frisuntl full'll) were interesterifledat 55"C fOl"24 h with SP435 lipase from Candida amaraica to produceplastic fats. As the amount of trisun increased, percentage free fatty acid,unseturered fatty acid/saturated teuy acid value, oxidizability. and theamount of 18:1 found at the slI-2 position of triglyceride productsincreased. Differential scanning calorimetry showed that the low-meltingcomponents in the product contained more 18:1 than the high-meltingcomponents. A 60:40 (w/w) ratio of lard to trisun had the widest plasticrange (3-26"C). The scaled-up reaction to produce this blend resulted in aproduct that had 60.1% Ig:1 at the $/1-2 position compared 10 44.9'1> forthe physical blend. The solid fat content of ee 60:40 intcresterified mix-ture resembled soft-type margarine oil.JADeS 75. 1339-1345 (l998).

ModirlCll.!ion or Butterfat by seiecuve H}'drolysis and lnleresterif\caUooby Lipase: Process aDd Product Characteriution, Victor M. BalcAQ'l,Asmo Kemppinenb. F. Xavier Malcaufl .•. and Paavo 1. Kala". uEscolaSuperior de Biotecnologia. UniversidaOe CalOlica Ponuguesa. 4200 Porte,Portugal, and Departments of bJ:ood Technology and cApplied Chemistryand Microbiology. University of Helsinki. Viikl:i 00014. Finland.

Butterfat was chemically modified via combined hydrolysis and inter-esterification. catalyzed by a commercial lipase immobilized OIItOa bun-dle of hydrophobic hollow fibers. The main goal of this research effortwas to engineer butterfat with improved nutritional properties by lakingIIdvanlllge of the 5n-I.3 specificity and fauy acid specificity of a lipase inhydrolysis and ester Interchange reactions. and concomitantly decrease itslevel of long-chain saturated fatty acid residues (';z .. lauric. myristic, andpalmitic acids) and change its melting propenies. All reactions were car-ried OUIat 4O"C in a sotvem-tree system under controlled water activity,and their extent was mooiton:d "ia cbromatographlc assays for free fauyacids. esterified fatty acid moieties. and triacylglycerols; the thermalbehavior of the modified butterfat was also assessed ~ia calorimetry.Lipase-modified butterfat possesses a wider melting temperature rangethan regular butterfat. The total saturnted lriacylglycerols decreased hy2.2%. whereas triacylglycerols with 28-46 acyl carbons (which cont.ainedIWOor uvee lauric. myristic. or palmitic acid moieties) decreased by 13%.The total monoene triacylglycerols increased by 5.4%, whereas polyenetrillCylglycerols decreased by 2.9%. The triecylglycerols of intcresterifiedbutterfat had ca. 10.9'1> less lauric, ]O.7~ less myristic, and 13.~ lesspalmitic acid residues than those of the original butterfat.JAOCS 75. 1347-1358 (1998).

Enzymatic Glycerolysls or Soybean on, H. Noureddini" and S.E.Harmeier, Department of Chemical Engineering, University ofNebraska-Lincoln, Lincoln, Nebraska 68588"()126.

Enzymatic glycerolysis of soybean oil was studied. Of the nine tlpasesthat were tested in the initial screening. Pseudomonus sp- resulted in lbehighe5t yield of monogfycendes. Lipase from PseudOfTlOlUU sp. was fur-lner studied fOl"the influence of temperature. thermal slllbility, enzyme/oilratio, and glycerol/oil ratio. A full factorial optimization approach wasperformed. The following conditions were lested over the specifiedranges: temperature (30--7O"C). thermal slability (30--70"C). enzyme/oilralio (0.0.5-0.2 g enzyme/IO g oil). glycerol/oil ratio (1:1-3: I glycerol/oilmolar ratio) and I h reaction time. The stabilily of the enzyme at the reec-tion temperature was also incorporated as a separate variable. AI tempera-lures above 4O"C enzyme denaturation olTsetthe higher activity. The opti-mal conditions were selected 10 be the basis for a continuous process:4O"C. a glycerol/oil molar ratio of 2:1. and an enzyme/oil ratio of 0.1 genzyrnellO g oil. A definition fOl"glycerolysis activity was adopted. TIleglycerolysis activity (I GU) was defined as the amount of enzyme neces-sary 10consume I ~I of substrate (glycerol and oil) per minute. Thisresearch is intended 10explore the relICtion parameters that are importantin a continuous enzymatic glycerolysis process.JAOCS 75. 1359-1365 (l99g).

'tUnoienH: Add in Zygomycetous .'ung;: Srogiln nugaloaupus. J.D.weere-. F. Shewmaker. and S.R. Gandhi. Department of Botany andMicrobiology, Alabama Agricultural Experiment Station. AuburnUniversity, Auburn, Alabama 36849.

TIle fatty acids of over 150 species and isolates of zygomycetous fungiwere analy:t.ed. and il was found thai. y-linolenic acid (GLA) composed 35 to62%ofthe iotaI terry acids in several species. i.e .. Citrtru!11a 5implu, Mucor;ndiclU. Srogirt5 megalocarpsu (ATCC 18025). and Z)"gom)"lIchlU m~l-lierit II. (UAMH 1556). Further study of S. mtgalocarpu5 showed that thelotal lipid content of the mycelium could be increased from 9.8% of the drybiomass to 20 to 25% when grown in a medium with a high carbon/nitrogenralio. Under these conditions, the GLA content of the triacyglycerols in-creased during culture development. even during the SlIItionary phase, bulremained relatively constant in the phospholipid fraction. Nonsaponifiablelipid represenled 4% of the total lipid, and tne major sterol among 14 ottlersdetected was ergoMemI at 52% of the total. Pho!;:phoIipids composed 7~ oftne total lipid with phosphatidylethanolamine and phospbatidylcholine rep-resenting 53 and 39% of the total. respectively.JAOCS 75.1367-1372 (1998).

Lleer Upids and FaUy Adds of the Sting Ray Dasyalis bfuhri (BIYlh6.Debasish Pa]a. Dipankar Banerjee", l'.lIlln K. PamU, Amarendra Patra ,and Amitabha Ghosha .•. aDepanment of Chemistry. Bose Institute.Calcutta 700009, India, and bCAS on Natura] Products. Depanmenl ofChemistry. College of Science & Technology. Universily of Calcutta.Calcutta 700009. India.

The sting ray, DasyaIis bieeuri (Blyth), has been studied for lipids andfatty acids of its liver. The neutral lipids identified were hydrocarbons, wuesters, steryl esters. I-O-alkyl·2.34iacylglycerols. triacylglycerols. andsterols. Neutral lipids were predominanl (91.8~). major components beingtriecylglycercls (92.7%). PoIyenoic fatty acids of n-3 series. liz. eicosapen-taenoic acid and docosahexaeooic acid. were high in the phospholipid andneutral lipid fractions. Owllesterol was the major component (67.9%) in thesteryl ester fnlction. Glyceryl ethers. with chain lengths up 10 30 carbons.were recorded with unsaturated. anteiso. tso. and normal chains. In waxester alcoOols. up 10 32<atbon chains were ra:orded. Hydrocarbons wereup to 36-carbon chains with antetso, iso, and normal chains. Amongbnlnehcd chain hydrocarbons. prisaane was the major component (6.7%)and squalene was present at the level of 3.5%. Chimyl and batyl alcoholbackbones were the major components found in I-O-alkyI4iocylglycerols.JAOCS 75. 1373-1378 (1998).

Eft'fd of Pro-Oxidants 00 the Occurrence of 2-f>tontyl Pyridine In SoyProfeln Isolate. W.L Boatrighr", A.D. Crum. and Q. Lei. Animal ScienceDepartment, University of KenRlCky. Lexington. Kentucky 40546-0215.

Levels of 2-pentyl pyridine in hexane-defatted soybean flours pre-pared from Burlison. Stressland. and Probsl varieties and a variely null forlipoxygenase 1.2. and 3 were determined using an internal standard ofdeuterium-labeled 2·penlyt pyridine. "These defalted nours conlllined from

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ABSTRACTS FROM AOCS JOURNALS

0.06 to 0.51 ppm 2-penl)'l pyridine. The Ilcars from upoxygenase-nunand SU"eSSlandvarieties of soybeans contained the lowest levels. ControlIreeze-dned soy protein isolates (SPI) prepared from ~falled·nO\lrs allcontained from 0.16 100.18 ppm 2-penl)'1 pyridine. Adding pro-oxidants(FeCI)_ CUC]2) or exposing tile protein slurries to ultraviolet light duringSPI processing increased the level of z-pemyt pyridine in the proIein iso-lates by up (0 1256 percent above tile control Burlison. Stresstaed. andProbst SPI. The Cueh andlor UV rreatmem contributed the IDI'l!e51iocru.se in exh case. Tiie same prt)-Qxidant and UV treatmentS contribut-ed no signifICant increases in lhe level of 2-penl)'1 pyridine in the proteinisolates from the lipoxygenase null SPI.JAOCS 75.1379-1383 (1998).

Key Odorants of Fn'nch Fne., Robert K. Wagner and Werner Orosche.Deutsche Forschungsanstalt fIIr Lebensminekbemie. 1)..85748 Garching.Germany.

Twenty-one compounds, ....hich had been screened in preceding exper-iments as poIent odomnts of french fries prepared in palm oil (PO). wen:quantified by !>table isotope dilution IlSsays. Nineteen odorants were dis·solved in sunflower oil in concentrations equal to tOOse in PO. The Ilavorprofile of the model obI:a.ined was close to that of a real sample of PO. Acomparison of the complete model with models lacking one or more com-pounds indicated the following key odorants of PO: 2-ethyl-3.5-di meth y Ipyrui ne. 3-eth y 1-2. 5-d imet hyl Pyrazi ne, 2,3 ·dieth yl- 5·methylpyraaine. 3-isobutyl-2-metho~ypyrazine. (E.ZJ- and (E.E)-2.4-decadienal. Inllls·4,5-epox y.(E). z-decenat. 4·hydroxy-2.5-dimet hyl-3(2H)-furanone. methylpropanal. 2- and 3-metbylbutanal, andmethanethiol. Replacement of palm oil by coconut fat led to a coconutnote in the profile of french fries. j-Ocmlectone was identified as a majorcontributor to this rKlte:JAOeS75.1385-1392(1998).

Effect of Vacuum Frying on the Qxidoth'e Stability of Oils. Shyi·UangShyu. Lung-Bin Hau, and Lucy Sun Hwang -, Graduate Institute of FoodScience and Technology. National Taiwan University. Taipei, Taiwan,106. Republic ofChinu.

The purpose of this study WIlSto evaluate frying oil quality wilh dif-ferent assessment methods during vacuum frying of carrot slices. In sixronsecutlve days, palm oil, lard, and soybean oil were fried under vacuumat 105·C for 20 min each hour in an 8-h shift. Peroxide value. acid value,carbonyl value, total polar components, dielectric COnStalll (Food OilSensor reading). viscosity. and fally acid composition were used to evalu-ate the quality of these oils. Results showed that palm oil and lard possessgreater thennal stability than soybean oil. The decrease in CI8:2/C16:0ratio was greater for soybean oil than the other two oils. Of the assess-ment methods used, peroxide value, carbonyl value. total polar compo-nents. and dielectric constant all showed good correlation with frying timeand between each other, Viscosity was suitable to assess vacuum-friedlard and soybean oil, bill rKltpalm oil. The measurement of dielectric con-stant. on the other hand. appeared to be unsuitable to assess vacuum-friedsoybean oil.JAOeS 75. 1393-1398 (1998).

The rnnuence or Carotenoids and Tocopherols on Ihe Slablllty ofSamO"eT Seed Oil During lIeat-Catalyzed Oxidation. L.K. Henry".G.L. Catignanio. and S.J. SchWartlb,-, «Depanrnenr of Food Science.North Carolina State University. Raleigh, Nonh Carolina 27695·7624 andbDepartment of Food Science and Technology, TIle Ohio State University.Columbus. Ohio 43210-1097.

llIe stability and antioxidant effects of carotenoids and tocopherols insafflower seed oil were evaluated under thennal (7S·C) and oxidative con-ditions and the oxidative stability index (OSI) detennined. The antioxidantcapability ofbutylated hydroxy toluene (BHn was also compared with thatofjl-carotene in a model system. Lycopene and jl-camtene (I to 2000 ppm)....ere heated (7S"C) and exposed to air (2.S psi) in an oxidative stability in-strument. ~-Carotene had no antioxidant effect at concentrations below500 ppm. because il did rKlt alter the induction time. Lycopene increasedthe induction time only slightly at low concentrations. However, at con-cemranons greater than 500 ppm. both IJ-carotene and IYCOJ'C'neacted asprooxidants. significantly dec:reasing the indUCIion period. AI the highestconcentration. 2000 ppm, lycopene was more procxidative than Il-carotene. Q- and "\"-Tocopherol (concentration. 1000 ppm) delayed the in·

duct ion time by 16 and 26 h. respectively. There was no cooperative inter-action between a-tocopherol and li<aTOlene in delaying the OIl5Ctof oxi-dation. Furthermore. BHT wu significantly more antioxidative than ~_carotene. Thus. under thennal and oxidative conditions.lJ-carotene couldrKltdelay the onsct of oxidation. The tocopherols and BIiT were effectivein suppressing the onset of oxidation. as determined by the oxidative sta-bility measurement.JAOCS 75. 1399-1402 (1998).

Urea Ccmptexauen tor the Rapid. Ecolngically Responsible."ntelionation of ."ally Adds from Setd Oil, Douglas G. Haycso. Ylva C.Bengusonc• James M. Van Alstineb.c, •. and Fredrik Seuerwatlc.DepanmenlS of °Chemical Engineering and bcrn:mistry. University ofAlabama in Huntsville. Huntsville. Alabama 35899. and '"Department ofChemical Engineering and Technology. Royal Institute of Technology.SE-l00 44 Stockholm. S....eden.

Urea complex formation is a dusK: method for fractionating faltyacids from seed and other oils. The method's simplicity. ease of scaling.and ecological friendliness suggesl its reevaluation in Il'gard to modemfractionation challenges. In keeping with this. a simple. quick. ieexpen-sive, robust. and environmentally friendly procedure was developed forreducing the suturated free falty acid (FFA) conrern of saponified Jew-ere-cic acid rapeseed oil (LEAR). The process involves formation of a h0mo-geneous M·C solution of FFA and urea in 95% ethanol (5% water), fol-lowed by cooling of the resultant urea complex sluny to room tempera·ture. The urea complex and liquid phases are separated by gravity flltra-tion. and the urea isolated in each phase is Il'mo\"ed by extraction with60°C water. Saturated LEAR oil FFA preferentially formed urea complex-es easily separated from the eoncompiexed. mostly unsaturated FFA. themain product of inteTCSI.The effects of single- vs. oocbie-srage fractiona-tions and several other variables (component mass or volume r-~tios. tern-perature. ethanol solvent to water ratio) were preliminarily evaluated.Results demonstrmed Ihe robustness. reproducibility, and simplicity of Ihemethod.JAOeS 75, 1403-1409 (1998).

I>rct~tment or Corn Oll for l'hyslcal Rennlng, Rosemer Anroniessi" .•.Walter ESlevesh, and Antonio rose de Almeida Meirel1esb. uEMBRAPA_CTAA. Rio de Janeiro. RJ, Brazil, CEP 23020-470. and bFaculdade deEngenhariu de Alimemos-UNICAMP. Campinas, SP. Br-ail.

Crude com oil that contained 380 ppm of phosphorus and 5% of freefauy acids was degummed. bleached. and winterized for physical refining.The pretremmenr and lhe sleam·refining conditions were studied in pilotplant scale (2 kgibmch). The efficiency of wet degumming and of the totaldegumming processes, at different temperatures, was evaluated. TriSyl sili-ca was tested as an auxiliary agent in the reduction of me phosphorus con-lent before bleaching. TIle experimerual conditions of the physical refiningwere: temperature at 240 or 25O"C; 8 \0 18 mbar vacuum. WId distillationtime varying from I 103 h. Degumming at 10 or 30·C resulted in meremoval of more phosphorus Ihan at 70·C. Water degumming was moreefficient than tbe processes of lotal degumming or acid degumming. Comoil. degummed at 10 or JOOC, after bleaching passed the cold lest. irrespec-tive of the degumming agent used. Degumming and winterization tookplace simultaneously ot lhese temperatures. The pretreatment was able toreduce the phosphorus comem to less than 5 ppm. The amount of bleach-ing earth was reduced by canying oot dry dc:gumming or by using silicabefore bleaching. Com oilacidily. after physical refining. varied from 0.49to 1.87%, depending on the residence time. Contrary to alkali Il'fining.physical refining did rKltpromote color removal due to the fixation of pig_ments present in the crude COllIoil.JAOCS 75, 1411-1415 (1998).

Commerdal Prcducrlon of Chla in Nor1h"estern Argentina. Wayne:Coates- and Ricardo AyC1""J)j(h). Bioresources Research Facility. Office ofArid L..andsStudies, The University of Arizona. Tucson. Ari:ron.a 85706.

The economy of nonh,,·estem Argentina depends heavily on 5ugarand tobacco. [)qnMed prices for these crops in recent yean; have causedsignIficant CCOfH.>mil;problems, and altemath·e crops are actively beingsought. Chia (SoMI' hllfNInica L). a source of industrial oil for the 005-metics indu!>try and (1)-3a-linolenic acid for the food industry. is one newcrop tilat could help diversify the local economy. A projecl to de'·elopchia as a commercial crop was initiated in 1991. In 1996. J3 fields were

INFORM Vol. 9. no. 11 (Novembef 1998)

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commercially grown in IWO provinces of northwestern Argentina.Biomass prodoction and seed yields were affected by weather, location.and production precoces. Average seed yield was 606 kgrha. Oil oonlcnland fauy acid composition varied between fields.JA.OCS 7J, 1417-1420(1998).

Recovery or y-Oryzanol From Rice Bran Oil with Silica-BasedContinuous Chromatography. Michael Saskatl •• and Gordon J.Rossiterb, QAudubon Sugar tnsuune. Louisiana State UniversityAgricultural Center. Balon Rouge, Louisiana 70803. and bAdvancedSepanllion T«hoologies.ll'IC .• L..al:eland. florida 33801.

A simulated moving bed chromatography separator was tested forrecovery of l-OI)'ZlIool from dcgummed and dewaxed rice bran oil thatcontained 1.2 \0 1.6-" y-oryunol. A crude product with 12-15'1> of y-OI)'Unol was obtained and a 90 to 9S'l> pun: product was recovered from!he concenlralC by CJ')'stalliz.alion from beptane. With the recycling of thecrystallization liquor, an o\'erall"'t<l')'Vll101 recovery of8:i to 9Q'I, is feasi-ble and is potentially higher than !he recovery in !he conveeuonat soap-stock-based process.JAOCS 75.1421-1427 (1998).

El(In.ction of 011 rrom Meado .. foam Fla);.l'S. Kenneth D. Carlsona. BlissS. Phillips(J·-. Terry A. Isbella. and Terry C. N~lsenb. aNew CropsResearch. NCAUR. MWA. ARS. USDA and bOffice of the Area Director.MWA. ARS. USDA. Peoria. Illinois 61604.

As pan of a program to improve meadowtoam seed processing. theauthors examined the effects of seed moisture. seed temperatull:. and flaldngroll opening on oil extraction efficiency in meadowfoam flakes. Flakes wen:prepared using a Wolf Mill with dual Ilorizontal. unheated 12-in. diameterrolls. Roll openings of 0.005. 0.013. and 0.02Q in. (0.127. 0.330. and 0308mm. respectively) gave average flake thickneMc:s of 0.013. 0.021. and 0.031in.. respectively (0.330. 0.j33. and 0.787 mm). Seed moistures of 9. 12. andIj% and seed tempemtUIl:S of 6.5. 190. and 2100F (18. 88. and CJ9OC) clKKnfor flaking well: known to provide a range of conditiom MliUlblefor enzyme:inactivation during seed cooking prior to flaking. Experimental flakes well:examined for extractable oil content (petroleum ether extraction); this wascompared to tOOl.Ioil CQIllent (31.5%) detem\ined on finely ground flakes.Roll opening was !he dominant variable detem\ining flake thickness. tbe pri-mary parameter affecting oil extmc1ion effICiency. ThUs. the thinnest flakesat 0,013 in. well: only slightly less extract.able (29.8") than finely groundflakes (31,5">, but intermediate (0.021 in.) and thick (0.031 in.) flakes well:significantly less extractable (28.0 and 26.0%. respectively). 'There was aslight but significant (P < 0.01) trend towanlthicker flak:es with increasingseed moistull: (Ij > 12> 9'1» during flaking. A similar trend to thickerflakes with increasing temperature was significant (P < 0.01) only for thethickest flakes produced at the lorgest roll opening (0.020 in.). Lower seedmoiSlull: and higher seed temperature signifkanuy impacted extract.able oilcontent of the thickest Ilakes. but negligibly affected extractability of thethinnest flakes. The Duthors conclude that meadowfoam flakes must be asthin as possible (e.g .. 4l.015 in.) for effICient oil extraction. Further. seedcooking temperatures >190°F at rneisrures >10% and <15 .. that are ade-quate ro-emoem enzyme inactivation in the whole seed are also suit.able forseed flaking,JAOCS 75. 1429-1436 (1998).

Deacidification of a Synthetic Oil with an Anion Exchange Resin.Vol~rie Eychenne and 'Uphirin Mculoungui". Laboratoire de ChimieAgro-Indusrrlette UA INRA 31A1010. Ecole Nationale Superieure deChimle de Toulouse. INP Toulouse. 31077 Toulouse Cedex 4. France.

Esters of mmethylolpropane were prepared by reaction of trimethylol-propane with erucic acid. tfnreacred erucic acid was eliminated by fixa-lion on an anion exchange resin to produce an oil with a low free fattyacid content. The authors describe the deacidification of the reaction prod-uct by Lewatit MPj()()A and MP600 resins in a fixed-bed reactor or in astirred reactor. The discontinuous process gave the besI: results with tbeLewatit MP600 resin in a stirred Il:aclor with a 99'1> yield. The acid valuewas below 0.1 after less than I h of contact.JAOCS 75. 1437-1440 (1998).

Comparison of "'our Accdenlled Stability Methods ror Lard and TallowWith and Without Antioxidants. Chao liang"'- and Kilen SchWarzer".aKernin Industries (Asia) Pte Ltd .. Singapore 758200. and bKemin

Europa N.V.. lndustriezene wotrnee. 2200 Herentals. Belgium.The oxidative stability of lard and tallow with and without antioxi-

dunts was evaluated by four accelemted stability methods. the active oxy-gen method (AOM). the oxygen bomb test. the Rancimat method. and theSchaal oven test. The results indicated that the oxidative stability of ani-mal fats and the relative effectiveness of an antioxidant in the fats couldhave different mechanisms. When the protective index was used todemonstmte the relative effectiveness of the antioxidants. the results sug-gested thllt the Roncimat Method may be !he least reliable method com-~ with AOM. oxygen bomb test. and Schaal even ~. More than oneaccelerated stability method is recommended roc evaluating the effecti"e-ness of an antioxidant or the oxidative stability of fats.JADeS 75. 1441-1443 (1998).

Calculating the Iodine "alut ror Marine Oils rrom fat!)· Add Profiles.Bryan Ham-, Robert Shelton. Boyce Butler. and Paul Thionville.Thionvillc Laboratories. New Orleans, Louisiana 70183.

The iodine values of marine oils wen: dill:Ctly calculated from fattyacid profiles by using reacting ratios (calculation factors) between 12(iodine) and either the fally acids bound to a triglyceride or the free fattyacids. A total of 20 factors were incorporated from C14:1 to C24:1.placed into an Exccl~ spreadsheet. and used to calculate the iodine val-ues. The calculated values well: then compared to the oil's iodine valueobtained by the traditionul titmtion method. The results indicate that thismethod can be used to obtain the iodine value of marine oils directly fromthe oil's fatly acid composition. thus giving two results from one analysis.JAOeS7j.I44S--1446(1998).

UltnLwnk Allenuatkm of Edible Oi ts. Ratjika Chanamai and O. JulianMcClements-. Biopolymers and Colloids Research Laboratory.Department of Food Science. University of Massachusetts. Amherst.Massachusetts 01003.

The frequency dependence (1-60 MHz) of the ultrasonic attenuationcoefficient of canota oil. com oil. olive oil. peanut oil. safflower oil. soy-bean oil. and sunflower oil was measured at 25°C, lbe attenuation coeffi-cient of all the oils could be described by the relation: a --Ar (with Abetween 6 and 40 x lO-12. and 11 between 1.74 and 1.86).JAOCS 75. 1447-1448 (1998).

Occurrence or Conjugated Llnolek Add Isomers in Beef. Sonja Fritscheand Jan Fritsche", Institute of Biochemistry and Food Chemistry.University of Hamburg. 20146 Hamburg. Germany.

The amounts of .6.9All-oonjugatcd linoleic acid (CLA) isomers wen:determined in loin-associated fat samples of bulls (11 " 6) and stem; (11" 7)by capillary gas chromatogruphy of fatty acid methyl esrer (FAME) deriva-tives. The main CLA·isomer-18:2 c9.11l-provided approximately 0.76:!:O.lj" Dod 0.86:t 0.15'), of tOOlIFAME in bulls and steers. respectively. Nodiffell:occs (p > 0.05) wen: observed between !he CLA isomer distributionof bulls (r9.c II. 0.026:t 0.014'),; c9.c II. O.Q1j :t 0.008": and 19.111. 0.029:t 0,CXl3.. ) and steers (r9.c II. 0.027:t 0.Q14%; c9.c 11. O.Q1j:!: OJ)05'),; and19.111.0.030:t 0.007'),).JAOeS 75.1449-1431 (1998).

Antioxidant I'ropertll'll or Iksrerrioxllmine E, a New H)'droxllmateAntioxidant. E. Sblmoni". M. Ampel'", H. Zillmer". and I. Neemana.-."Department of Food Engineering and Biotechnology. Technion-IsraelInstitute of Technology. Haifa 32000. Israel. and bUniversity of Tilbingen.D-74OO TUbingen. Federal Republic of Germany.

Antio~idunt propenes of de.~fl'nioxamine E. a cyclic trihydroxamHteproduced by microorganisms. well: tested and compared to those of des-Iemoxarntne Band butylated hydruxyanisole (BHA). Desfemoxamlne Eexhibited significant antioxidant effects in linoleic acid emulsions as w~1Ias in emulsions of linoleic acid and fH;arotene. In concentrations of 100ppm, the effect of both desferrioxamfnes in linoleic acid emulsion wasequal to that of BHA. The amiexidam activit), of the desferrioxamines inemulsions of ~<arotene and linoleic acid was significantly higher than!hat of BHA. In addition. the initial nile of fH;arotene desiruclion was sig-nifICantly lower when desferrioxamines were added to the emulsion.JAOCS 75. 14B-14jj (1998).

Triterpene Airoltots and ""au}' Acids in Lipids and NousaponiliableMaller or JApsonQ communis L. Sub!'ipecies cQmmunis (A5teraceae).

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ABSTRACTS FROM AOCS JOURNALS

Didier FonlllneJQ,-, Michael KatgoloLAJain Gueillierb, and Claude VieiD.aLaboratory of Phlll'TIlocognosy and "Laboratory of Medicinal Chemistry.Faculty of Pharmaceutical Sciences, University of Tours, 37 200 Tours.F_.

The oil content of s.amples of aerial pam of wmpsarw communi! L.subsp. commUni!, harvested in Intire Cl Loire (Frnnce) at different periods.varies from 1.1 to 2.1'1>. Nonsaponifiable matter in these samples repre-sents 36.0 10 65.7'1> of the oil. Yic:lds of rrirerpene alcohols of 000-saponifiable matter (25,9 10 81.8%) were determined by preparative thin-layer dlll)malograpliy after saponificatice. Seven of them were identifiedby gas chromatography-mass spectrometry (GC-MS). Six of the fallyacids in the aerial parts have also been identified by GC-MS.11Je seeds ofL communis ecntain 2.6% oil.JAOCS 75. 1457-1459 (1998).

Optical Resolution of {:t:}-Thna-9,IO,I6- Trih,'drnxy Hexad«anok AcidUsing (-)8rudne. Navdeep B. Malkar and V.G. Kumere. HindustanLever Research Centre, Aooheri (E.) Chakala, Mumbal 4Q0.099. India.

The optical resolution of (%)/hnw-9, 10.I6-trihydroxy hexadecanoicacid was achieved by fractional crystallization using {-)brucine.Formation of an esrotioe during decomposition of the {-)brucine complexwas observed to interfere with the separation of the optically pure materi-al. This was corrected by convening the esonoe to {+}lhrw-9,10.I6-lri·hydroxy hexadecanoic acid \'ia alcoholic alkaline hydrolysis followed byneutralization. Enamiomeric purity was dctennined by chiral lanthanidenuclear magnetic Te!iOfUII'ICe shift reagent.JA.OCS 75. 1461-1463 (1998).

On the Use and Misuse of the Avrami &Juation in Cbaracterizlltion ofthe Kinetics or .'11 Cryttalllllltion. Alejandro G. Marangoni·.Department of Food Science, University of Guelph. Guelph. OnuuioNIG2WI, Canada.

The Avrami model is widely used in the analysis of crystalliutionkinetic data. UnfOl1unately, the use of the original model has been aban-doned in favor of modified versions. 'The modifications are largely lIIti-trary and create a dependence between the Avrami constant and theAvrami exponent. From a curve-filling point of view. no advantages existin using the modified over the original form of the Avrami model. Theorder of a polynomial fit to crystallization data is not equivalent to theAvrami exponent. 1bc use of turbidity measurements for the quantitativecharacterization of crysralllzerion kinetics is not valid.JAOCS 75. 1465-1467 (1998).

Divergent Incorporatlnn of Dietnry trans Fatty Acids in CirrerentSerum Lijlid Fractions, Helvi M. Vidg/en/"·, Anne M. Lcuherumu".Jyrkl J. Agren/I•h, Ursulu S. Schwab", and Malli U. Uuaitupa".Departments of aClinical Nutrition and bphysiology. University ofKuopio, Kuopio. Finland.

Trans futty acids may be involved in atherosclerotic vascular dis-eases. We investigated the incorporation of dietary trans fatty acids andoleic acid into the serum triglycerides (TG). cholesterol esters (CE).and phospholipids (PL). Fourteen healthy female volunteers, aged 23.2:t 3.1 yr (mean % SO), body mass index 20.8 :t 2.1 kgfm2 participatedin this study. A11 subjects consumed both a Irant fatty acid-enricheddiet (TRANS diet) and an oleic acid-enriched diet (OLEIC diet) for 4wk according to a randomized crossover design. Both experimental dietperiods were preceded by consumption of a baseline diet for 2 wkwhich supplied 37'1> of total energy (E'I» as fat: 18 E'I> from saturatedfauy acids (SFA), 12 E'I> from monounSatunlled fally acids. and 6 E'I>from polyunsaturated fally acids. Five E'I> of the SFA in the buc:linediet was replaced by Irant fatty acids (18:11 and 18:2c.I + 18:21.1.where c is cis and, is IrollS) in the TRANS diet and by oleic acid

(18: I n-9) in the OLEIC diet. After the TRANS diet, the proponions of18:11 and 18:2, increased (P < 0.001) in all serum lipid Iracticns ana-lyaed. The increase of 18: II in TG and PL (1.80:t 0.28 vs. 5.26:t 1.40:1.07 % 0.34 V5. 3.39 % 0.76 mol'l> of total Iany acids. respectively) wasmarkedly higher than that in CE (0.44 :t 0.07 vs. 0.92 % 0.26). whereasthat of 18:2, was nearly the same in all three fractions. The proportionsof palmitic. stearic. arachidonic. and eicosapemaenoic acids in TG, CE,and PL and that of oleic acid in TG and CE were decreased when com-pared with the baseline value. In contrast. the proportion of palmitolelcacid in TG and PL and that of linoleic acid in PL increased on theTRANS diet. After consumption of the OLEIC diet. the proportion ofoleic acid increased in all three lipid fractions analyzed. and the per-centage increase was nearly the same in all fractions. In cornrast. theproportions of 18: I / in TG and PL and 18:2, in TG and CE decreasedwhen compared with the baseline value. In conclusion. a moderateincrease in dietary trans fatty acids resulted in a marked incorporationinto serum lipids and decreased the conversion of linoleic acid to it5more unsaturated long-chain metabolites. Analysis of 18: I, from serumTG and PL seems 10 reflect reliably the dietary intake of this fatty acid.Upids JJ. 955-962 (J998).

Identification ol Conjugated Linoleic Add Isomers in Cheese by GILSChromatography, Silver Ion High PerformllOce LiquidChromlltography and MIlSSSpectral Reconstructed Ion Profil~.Comparison of Chromatograrhic Elution Sequences. Najibu11ahSehat", John K.G. Kramerb .. Magdi M. Mouoba". Martin P.Yurawec;pf',·. John A.G. Roacha. Klaus Eulittl'. Kim M. Morehouse",and Youh KuD. "U.S. Food and Drug Administraucn, Center for FoodSafety and Applied Nutrilion. Washington. DC 20204. and bSouthemCrop Protection. Food Research Center. Agriculture and Agri-FoodCanada. Guelph. Ontario N IG2WI. Canada.

Comrnen:ial cheese products were analyzed for !beir C(lmposition andcontent of conjugated linoleic acid (CLA) isomen. The total lipids wereU!raCted from cheese usiog peeoreum ether/diethyl ether and ITlC'lhylatedusing NaOCH3' The fatly acid methyl eslers (FAME) were separated bygas chromatography (Ge). using a lOO-m polar capillary column, intooine minor peaks besides that of the major rumenic acid. 9c.1 lr-octedeca-dienoic acid (18:2). and WeTC attributed to 19 CLA isomers. By using sil-ver ion-high performance liquid chromatography (Ag+-HPLC), CLA iso-mers were resolved into seven lranS"rans (5-9'1». three cturrans(10-13'1», and five cis.cis «1'1» peaks. totaling 15, in addition to that ofthe 9<:'.111-18:2 (78-84'k). The FAME of total cheese lipids were fraction •.ated by semi preparative Ag+ -HPLC and convened to their 4,4-dimethyl-cxeaonre derivatives after hydrolysis to free fany acids. The geomemcerconfiguration of the CLA isomers was confirmed by GC--direct deposi-tion-Fourier transform infrared. and their double bond positions wereestubllshed by GC-el~tron ioni-ution mass spectrometry. Reconstructedmass spectral ion profiles ofthc m + 2 allylic ion and the m + 3 ion (wherem is the position of the second double bond in the parent conjugated fattyacid) were used to identify the minor CLA isomers in cheese. Cheese con-tained 7/.9c-18:2 and the previously unreported I 1/,13c-18:2 and 12c,14,-18:2, and their ,r{JttS,mmsand cis. cis geometric isomers. Minor amountsof 8.1 0-. and 10.12-18:2 were also found. The predicted elution orders ofthe different CLA isomers on long polar capillary GC and Ag+-HPLCcolumns are also presented.Lipids 33. 963-971 (1998).

Influence or Long-Chain Polyunsaturated Fally Acids on InfantCognith'e Functlon, P. Wil1ansa .• , J.S. Forsythb. M.K. DiModugno", S.Varmab. ond M. Colvinb. Departments of apsychology and bChildHealth. University of Dundee. Dundee. 001 4HN. Scotland, UnitedKingdom.

Long-chain pclyunsaturaied fany acids (LCPUFA) are important rornonnal visual and conical development. In a previous study of the effc:ctsof LCPUFA on cognitive function of term infants at the age of 3 mon, weindicated that infants with evidence of reduced growth parameters at binhand impaired attention control as manifested by alate peak fixation duringinfam habiluation assessment may benefit from LCPUFA supplementa-tion. 'The aim or this prospective study was 10 determine whether LCPU-FA supplementation and late peak fiulion are related 10 means-end pr0b-lem-solving ability in these same infants at the age of9 moo. Term infants(58) WeTC randomized to one of two formulas containing either LCPUFA

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1095

or no LCPUFA and completed 4 mon of feeding with their formula.Cognitive function WIIS assessed al 3 mon of age by measures of infanthabituation. Infants (20 LCPUFA and 20 no-LCPUFA) completed theproblem-solving assessment at 9 mono Tbe IIQ-LCPUFA group had lowerscores on both measures of intention and number of solutions. but neitherof these differences WlIs significant. Analysis of covariance for the effeclSof group and peak fi~alion. covaried wilh gestation and birth weight,showed thai tixl number of solutions WIIS significantly reduced in tIw: latepeak-Ilxatlon infants receiving no LCPUFA (P < 0.02). Intention scorestended \0 be reduced in this group (P < 0.(6). The late peak-fixationinfants whoa received LCPUFA had solution and intention scores similar toearly peak-fixation infants receiving LCPUFA or no LCPUFA. Thesefindings suggest Ihm in term infunls who have reduced growth parametersat birth arK! who show evidence of impaired auemicn control. informationprocessing lind problem-solving ability in infancy may be enhanced byLCPUFA supplementation.Upids JJ, 973-980 (\998).

Tornillo Lycepene lind Low Density Lipoprotein Oxidation: A HumanDietary Internnllon Study. Sanjiv Agarwal and A. VenketcshweT Rao·.Dcpanment of Nutritional Sciences. Faculty of Medicine. University ofToronto. Toronto. Ontario M5S 3E2. Canada.

Increase in low density lipoprotein (LOL) oxidation is hypothesized tobe causally associated with increasing risk of atherosclerosis and coronaryheart disease. In recent epidemiological studies, tissue and serum levels oftycopene, a carotenoid available from tomatoes. have been found to beinversely related to risk of coronary hean disease. A srudy was undenak-en !O investigate the effect of dietary supplementation of lycopene onLOL oxidation in 19 healthy human SUbjeclS. Dietary Iycopene was pro-vided using tomato juice. spaghetti sauce. and tomato oleoresin for a peri-od of I wk each. Blood samples were ccttecred III the end of each treal-ment. Serum Iycopene was exirJlCted and measured by high-performanceliquid chromatography using an absot-bance detector. Serum LDL was iso-lated by precipitation with buffered heparin. and thiobarbituric acid-reac-tive substances (fBARS) arK! conjugated dieroes (CD) were measured toestimate LOL oxidation. Both methods. 10 measure LOL oxidation LOL-TBARS and LOL-CD. were in good agreement with ea.h other. Dietarysupplemenuation of Iycopene significantly increased serum Iycopene lev-els by at lellSt twofold. Although there was no change in serum cholesterollevels (tota], LOL, or high-density lipoprotein), serum lipid peroxidationand LOL oxidation were significantly decreased. Tbese results may haverelevance for decreasing the risk for coronary heart disease.l..I"pjds JJ. 981-984 (1998).

Low pH EnhanCe!i the Transfer of Carotene from Carrot Jui« toOlh·e Oil, Gillian T. Rich •. Anneuc Fillery-Travls. and Mary L. Parker.Institute of Food Research. Norwich Research Park. Norwich. NR4 7UA.United Kingdom.

A current model for carotenoid transport and absorption in the gutproposes an initial solubilizatlcn in the oil phase of dietary emulsions fol-lowed by Incorponaloe of the cerotenclds in mixed bite salt micelles. Toas5CSSthe relevance of the first stage of this model to what is observed invivo we have examined the transfer of carotene from carrot juice to oliveoil. Increased acidity enhanced the transfer from both whole juice andcarotene crystals isolated from carrot cteomoptasis. The transfer was sig-nificantly slower from whole juice. By using exogenous ~-carotene andmeasuring its transfer to oil in tile presence and absence of carrot juice wehave demonstrated that the inhibition of the transfer in juice arises. at leastin pan. from sctuble juice foctOB. Tbe inhibition is relieved by a fall inpH, which leads to lowering of the electric potential at the oil/aqueousphase interface and aggregation of carrot tissue including crystallinecarotene. Under conditions of low pH, oil droplets adhere to the tissueaggn:gutes, allowing carotene to pass into the oil. Our results provide anexplanation for why CD/"(J(eocabsorption I" vivo is depressc-d by condi-tions of low gastric acidity_Upids JJ. 985-992 (l998).

EIT«ls or .-ftdlna ~nariD 011 Rich in Nen-onic aDd Erucic Acids onthe Fatty Acid ComposItions or Sphlngomyelins from ErylhroC}1es,U~·er, and Brain or the Quaking Mouse Mutanl. Claire Cookl'. JoanBarneliD• Keith Couplandb. and John Sargenta .•. aOepanment ofBiological and Mol«ulu Scie~, Univ~ily of Stirling, Stirling FK9

4LA. United Kingdom. and bCroda Chemicals Ltd., Hull. Humberside,HU6 7PH. United Kingdom.

Feeding an oil from Lunllria bit",nis rich in 22: I n-9 arK! 24: I n-9 tohomozygous quaking (qk.qk) mice caused a llII"geincrease in the percent-age of 24: I n-9 arK!corresponding decreases in the percentage of 24:0 and22:0 in sphingoruyelies from liver. erythrocytes, and milk. Brain sphin-gomyelin from 2-wk-old qk.qk pups born to qk.qk mothers maintained onthe LurllJria oil had essentially normal percentage of 24: In-9 and 18:0. incontrast to pups born to mothers maintained on a control oil rich in18: In-9 whose brain sphingomyelin had a markedly reduced percentageof 24: I n-9 and an increased percentage of 18:0. After 2 wk and up to andbeyond weaning. the qk.qk pups from Lunaria-fed mothers weaned on tothe Lurwria diet had a marl.:edly decreased percentage of 24: In-9 in theirbrain sphingomyelin. accompanied by an increased percentage of 18:0. ascompared to heterozygous quaking mice. However. the percentage of24: I n-9 in brain sphingomyelin in qk.qk pups weaned on to the Lunariadiet continued throughout this period (2-8 wk possbirth) to be significant-ly higher than in qk.qk pups weaned on to the control diet. We concludethai dietary 24: In-9 influences the fatty acid composiuon of brain sphin_gomyelin in qk.ql.: mice, but only via the mother in pre- or early posmatatanimals. We funher consider thai the dietary effects may be elicited main-ly in the sphingomyelin of nonmyelinated bruin cells, and that the nervon-Ie acid in myelin sphingomyelin may be formed mainly by chain elonga-tion in oIigodcndrocytes from shorter chain fatty acid preccrsoes.Lipids JJ. 993-1000 (1998).

Comparison of RRR_a_ and all-rae-a-Tocopherol Uptake byPermanent Rat Skeletal Muscle Myoblasts (L6 cells): Eff«1S ofExcgeoccs Lipoprolein I.ipasc. Tetsuya Nakamuraa, Helga Reicherb,and Wolfgang Saltle,b,·, aSsai Co., Ltd., Vitamin E Technology Section.Tokyo 112-8088. Japan. and bUnivenity GI1I2.,Department of MedicalBiochemistry, A-801O Gm, Austria.

The purpose of the present investigation was to test whether penna-nent skeletal muscle cells (rat 1..6 cells) could serve as an in »aro modelfor a-tocopherol (aTocH) biodiscrimination studies. L.6 «lis were incu-bated in the presence of high density lipoprotein (HOL), low densitylipoprotein (LOL). and very low density lipOprotein (VLOL) labeled inthe lipid moiety with either nil-roc· or RRR-II4claTocH. These incuba-tions were performed either in the absence or in the presence of esoge-nously added bovine lipoprotein lipase (LPL) since skeletal muscle is oneof the major expression sites of LPL jn ,·i,'O. Time-dependem uptake stud-ies (up to 24 h) in the absence of LPL have shown that equipotent dosesof all-rac- and RRR-[ 14C]aTocH (l.36: I) led to almost identical accumu-lation of the tracer. independent of the lipoprotein class used as aTocHcarrier. With regurd to aTocH donor capacity. it appeared that HOL is themost potent aTocH donor, followed by LOL and VLOL. In the presenceof LPL. all-roc- and RRR-114C]aTocH uptake was significantly enhanced(between two- and tenfold). Biodlscelmination studies using chiral high-performance liquid chromatographic analysis with radiometric detectionof the corresponding methyl ether derivatives on a Chiralcel 00 columnhave demonstrated that the 2S- and 2R-isomers of ttTocll were taken upin a I: I llI!io by L6 cells independcnt of the absence or presence of LPL.In addition. we have not observed biodiscriminmion between the four 2R-isomers. i.e., there was no preferential accumulation of the RRR-isomer.These data suggest that L6 cells do not discriminate between differentaTocH isomers and thut the addition of endogenous LPL significantlyenhances the uptake of RRR- and aJl-flIc-aTocH.Lipids JJ. 1001-1008 (1998).

Metal.lon Stimulation lind Inhibition or Lysophospholipase D WhichGenerates Bioacllve LysophosphatIdic Acid in Rat Plasma. AkiTaTckumura". Maki Miyake, Osamu Yoshimoto. Mayumi Shimizu. andKenji Fokuzawa. Faculty of Pharmaceutical Sciences, "The Univenity ofTokushima. Tokushima 770-850:5. Japan.

We foond that lyscphospbclipase 0 (LPLO) in rat plasma prefenunsaturated to saturated Iysopbosphalidylcholiroes as substrates. generat-ing a biologically active lipid. lysophosphatidic acid. but it does nothydrolyze diacyl·phospholipids. In this study. this LPLO required a metalion for activity. Co2+ being the most effective, followed in order byZn2+. Mn2+, and Ni2+. This metal-ion-stimulated LPLO with uniquesubstnlle specifICity. which hall not been de5cribed previously. was sus-ceptible to thiol·blocking n:agenu and sc:ri"" CStentse inhibitors, bIlt IlOl

INFORM. \obi. 9. no. II (November 1998)

1096

We found thaI sesamtnots. a mix ture of sesaminol and its srereoiso-mers. are potent inhibilOf'S of the oxidation of low-density lipoproteininduced by 2.2'-azobis(2.4-dimcthylvaleronitriLe). Allhough sesaminolsstrongly inhibit lipid peroxldation related \0 their ability 10 scavenge treeradicals, their IIlltioxidant effects have not been investigated. To confirmthe involvement of the phenolic moiety in the sesaminol structure inantioxidant activity. s.csaminols were reacted with 2.Z'-azobis(2.4-dimethylvaleronimle). The reaction products were isolated by high-per-formance liquid chromalOgraphy and found to have a t-cyano-t.j-dimethyl-butyl·peroxyl group in their structures. These chemical struc-tures suggest thaI the sesamleols reacted with the alkylpell)xyl radicals 10form four major rnction prodUCts thai are sreeotsomers of each other.allhough the stereoc~mi5tty of eacll isomer lias not yet ~n confirmed.Further instrumental analyses of tile reaction products may increase ourundl'r.;llmding of the antioJtidant activity of sesaminols.lipidsJJ.I031-1036(1998).

ABSTRACTS FROM AOCS JOURNALS

to a lIislidine-modifying reagent. Ccnslstent with results using tlliol-modi-fying agents. sllon-chain fany aldehydes, secondary proaocts of lipid per-oxklation. were found to inllibit LPLD. Addition of dlbutylhydrcxy-toluc:ne or butylhydroJtyanisole to the plasma increased the activity of thisenzyme, probably in a manner independent of its amioxtdant activity,since another antioxidant. propyl gallate, was rather inhibitory. Theseresults suggest that rat plasma contains an active LPLD that diffcrs insome properties from other members of tile known phospholipase D fami-ly detected in animaltissues and body Iluids.lipids JJ. 1009-1015 (1998).

Lipid and FaUy Add Composition or Diffr~nt Fractions from RatUrinary TransitionMI .:pithelium. Reyna O. Caldl'ron·, MoniciGlocker. and Aldo R. Eynard, Primera Catedr.i de Hisrologia, Embriologiay Genetica. lnstinno de Biologia Celular. Fecuned de Ciencias Medicas,Univenidad Nacional de Cordoba, 5000 Cordoba. Argentina.

The phospholipid composition of rat urinary transitional epithelium(TE) and the fany acid composition of microsomal. mitochondrial,cytosolic. and plasma membrane: (PM) subcellular fractions were investi-gated. PM marker enzymes and ele<:tron microscopy analysis were used tocharacterize the PM fraction, which showed a distinctive lipid composi-tion compared to the general profile of PM from different sources. TIlelevels of cholesterol and sphingomyelin were not enriched in the PM frac-tion: on the other hand, the increased amounts of glycosphingolipids andphcsphatldylserine. and the decreased level of phosphatidylcholine fol-lowed the general features of a PM profile. This differential PM lipidcomposition may rene<:t the unique morphology of this mammal TE. con-sisting of concave plaques with an asymmetrical membmne unit. The dis-tribution of the double bond across the PM indicated a higber unsaturu.tionof the inner relative to the outer pan of the PM hemileaflet. In addition.the presence of 20:3n-9 nonessential fatty acid in II nonnal TE may repre-senr a characteristic fally acid metabolism of this epithelium.lipids 33. 1017-1022 (l998).

Allerallllns In !lellrt and Kidney Membrane Phcsphulipids InHyprrtenslon as Observed by 311' Nuclear Magnetic Resonance,Yuling Chi and Raj K. GuptP-. Depanment of Physiology and Biophysics,Albert Einstein College of Medicine of Yeshiva University. Bronx. NewYork 10461.

Abnormalities of phospholipids in hypertension have previously beendescribed in human erythrocyte. platelet. and plasma lipoproteins. Sincethe heart and kidney ore adversely affected by hypertension. we investi-gated possible altemtiuns in their membrane phospholipids. which couldplaya role in the derangement of intracellular ion balance widelyobserved in hypertension. The phospholipid compositions of heart andkidney from spontaneously hypertcnsive rats (SHR) and Wistar-Kyoto(WKY) rats were determined by using 31p nuclear magnetic resonance(NMR) spectroscopy. Absolute contents of nil phospholipids in hyperten-sive hearts and kidneys were significantly higher than in normotensivehearts and kidneys. EJtPressed as a fraction of total phospholipid. cardi-olipin (Cl) and phosphatidylcthanolamine plasmalogen (PEp) were sig-nificantly increased in SHR heans compared to WKY hearts (eL and PEpwere 7.95 j: 0.22% and 13.16:1: 0.35% in SHR vs. 7.01 ± 0.20% and 11.l9:I: 0.42% in WKY rats. P S; 0.05), but phosphntidylcthanolamine (PE) andphosphatktylcbcline (PC) were significantly decreased in SHR (PE andPC were 22.46 ± 0.37% and 44.81 ±0.43% in SHR vs. 24.02 ± 0.44% and46.01 ± 0.50% in WKY rau, p S 0.05). tn the phospholipids extractedfrom rat kidneys. the percentage of PE was significantly higher for SHRthan for WKY rats (20.37 :I: 0.6O'J> vs. 18.43 ± 0.37%. P S; 0.05). whilePEp and phosphatidylserine (PS) were liignifltamly lower for SHR (PEpand PS were 10.22 ± 0.36'1> and 8.42 ± 0.28% in SHRii V5. 11.29 ± 0.36%and 9.71 :I: 0.40% in WKY ruts. P S 0.05). The above ahenuions in phos-pholipid composition might contribute to the higher oxygen consumptionin the hypertensive hean and abnormal intracellular ion concentrationsand ion transport in the hean and the kidney in hypenensioe.lipidsJJ.I023-1030(1998)

Inhibition of 2.2'_Azobls(2,4_dlmethfl ..aleronitrite)_lndum LipidPcroxidat>on by Stsaminols, M)'ung-Hwa Kant', HitQlllka K.atsUUkib.and TosI'tihiko Osawaa-·. QLaboratory of Food and Biodynamics. Nago)'lUni"enity Gradu:lle School of 8ioagricultural Sciences. Nagoya 464-8601,Japan.1lJV:l bf"aculty of8ioresourn:s, Mie Unh~ty. Tsu, Mie 514, Japan.

INfORM, \obi. 9, no. 11 (November 1998)

S-Melhyl J)erlvatl ..u from Thllli Compounds by the PyrolytlcRraclion with Triml'thylsulronium n,.dro)[idt'. Klaus Vosmannll. ErikaKlcinb. and Nikolaus Weberb··. IIIn5titut fIIr Chemie und Physik derFette, and blnstilut fUr Biochemie und Technologie der Fette. H.P.Kaufrnarm-Insunn. BAGKF. 0-48141 MUnster, Germany,

Base-catalyzed trunscsterification of acyl lipids with methanol in thepresence of trimethylsulfonium hydro~ide (TMSH) is an easy and conve-nient method for the prt'parution of fatty ocid methyl esters for gas chrc-matography (Ge) analyses. Free fatty acids are convened to futty acidmethyl esters by the pyrolytic reaction with TMSH as well. We havefound that lipids and other compounds containing thiol groups are alsoconvened easily to the corresponding methyl sulfldes (methyl thioethers)by the pyrolytic reaction with TMSII occurring in the inje<:tor of the gaschromatograph. For exempre. alkane thiols such as dodecane thiol andocradecane thiol are convened to the: corresponding alkyl methyl sulfides.whereas bis(methylthio) derivatives are formed from a.(I)-alkane dithiols.e.g .. t.g-ocianedhhtol. and from 2,3-dimercaptopropan-l-ol (dimer-cuprol). Furthermore, 3!J-mercaplocholest-5-ene (thicchclesterol) is con-verted 10 3-metllyltlliocholest-5-enc by the same reaction. The S-methyl-arion reactions which finally lead to the corresponding methylthio deriva-tives of lipids and other compounds with thiol groups may be of diagnos-tic value for the structurnl analysis of sud compounds by GC andGCJnmss spectrometry.Lipit/dJ. 1037-I()41 (1998).

A SenllllutolDlltcd En~ynlllllc Method for Determlnatlcn ofNonl'Stl'rined .'lIlIy Add Concentration In Milk and Plasma, MichaelA. Christmassu.b .•. Leon R. Mitoulasl/, Peter E. Hartmann". and Peter G.Arthu ....', Departments ofl/Biochemistry und bHuman Movement. TheUniversity of We,~tcrn Australiu, Nedlands 6907, Austmlia.

An enzymatic assay for the determination of nonesterificd fatty acidconcentrations in milk and plasma is described. The procedure is semlau-tomated for use with a plate luminometer or plate spectrophotometer andenables routine batch processing of large numbers of small samples (SS~L). Following the activation of nonesterified fauy acids (NEFA) by acyl-CoA synthetase. the current assay utilizes UDP-glucose pyrophosphory-lase to link inorganic pyrophosphate to the production of NADH throughtile reactions catalyzed by phosphogfuccnunase and glucose-6-phosphatel-dellydrogenase. With this nssay sequence the formation of NADH fromNEFA is complete within SO min at 37OC. Enzymatic spectrophotometricIe<:hniques were unsuitahle for NEFA detennination in human milk due tothe opacity of the sample. TIle use of the NADH-Iuciferase system, hasO\'ercome this problem allowing the enzymatic detenninalion of NEFA inhuman milk. Sample collection and treatment procedures for milk andplasma have been developed to prevent enzymatic lipolysis and to limitinterference from enzymes prescnt in milk. The recovery of palmitic acidadded to milk and plasma samples was 94.9 ± 2.9 and 100 ± 4.5'1>. respec-th·ely.1bere was no difference (p .. 0.13) in plasma NEFA concentnuionsdetennined by the current method and a commercially available ...nzymat-io:: spectrophotometric technique (Waleo NEFA-C kit). Plasma NEFA con-centrations detennined by gas chromatography were 28~ hig~r com-pared to both the Waleo NEFA-C kit and the current method.lipids JJ. 1()43-1()49(1998).

1097

Journal of Surfactantsand Detergents

Alkyl PolJgluwsides as HJdrnCropes. Anna Matern', Asa Mallsson2.and Martin S\'cnsson-, Institute for Surface Chemistry (YKI). SE-114 86Stockholm, Sweden.

The hydrotropic effect of diff=:111 alkyl polygJucosides (APG) hasbeen studied and compared with a model hydrouupe. tclucl-e-saffcnicecid. 'The effect has been assessed by IWOdifferent methods: (i) as thecloud point elevation of a solution COolaiDing different noniooie surrec-lanlS upon lIddition of the hydrotmpe and (ii) the destabilization of liquidcrystalline phases in a ternary system. The effect of the hydrophobic alkylgroup length was found to be opposite in the IWO methods. APG withimerrowiale alkyl chain lengths (octyl alld decyl) was shown to be veryeffective in elevating the cloud point. while APG with a shan (butyl)group was the most efficient in destabilizing liquid crystalline phases inthe system of water. sodium dodecyl sulfate, and pentanol. Effects onphose behavior and cloud point elevation with addition of an APG arehighly dependent on its structure. However, the correlation between struc-rural effects as observed in the tWOmethods requires further study.JSD t, 485-489(1998). '

Solubiliution of Model Stratum Corneum Ltposomes by QuaternaryAmmonium Surfactants. A. de la Mazall.*. L. Coderchs. O. Lopez'", P.Gonzalezb. J. BauceiJsc, and J.L, Parrau, «Consejo Superior deInvestigaciones Cientff'icas (C.S.I.C.). Centro de Investigaci6n yDesarrollo (C.LD.), Departamento de Tensioactivos. 08034 Barcelona.Spain. IJ.rranslechnics S.L., 08006 Barcelona. Spain. and <UniversldadAut6noma de Barcelona (U.A.B.). Facultad de Veterinaria. 08193Beltarerra. Spain.

The solubilizing interactions of a series of quaternary ammoniumsurfactants [altyl chain If'ngths C-12 (DoTAB). C-14 (ff'TAB). and C-16 (HeTAB)] with liposomes formed by a mixture of lipids modelingthe stratum corneum (SC) lipid composition (40% cerarmdes. 25'l>cholesterol. 25% palmitic acid, and I~ of cholestf'ryl sulfate) wereinvestigated. Surfactantllipid molar ratios (Re) and bilayer/aqueousphase partition coefficients (K) ...-ere determined by monitoring changesin static light scauering of the system during solubilization. Free sur-factDnt concentration was always similar to the critical micelle concen-tration (CMC). A general assumption for phosphatidykholine (PC)Hposomes suggests that the free surfactant concentration must reachCMC for solubilization to occur. This assumption can be applied to SCHpcsomes in this study. and indicates that liposome solubilization wasmainly driven by mixed micelle formation. The Re and K parametersfell as the surfactant alkyl chain length decreased or CMC increased,Thus. a higher CMC componds to an increased ability of these surfac-tams to saturate or solubilize SC liposomes and to a lower degree ofpartitioning into liposomes or affinity with these bilayer structures. Theoverall balance of these opposing tendencies shows that TeTAB had thehighest effectiveness with respect to the saturation and solubilization ofSC structures in terms of total surfactant need~d to produce theseeffects, Different trends in surfactant interaction witb SC liposcmeswere observed when comparing R~ and K parameters with those for PClipcsomes. Because SC tiposomes were more resistant to the surfactantaction, the affinity of surfactants with these bilayer structures was high·er in all cases.JSD I, 491-497 (1998).

Pyrlmidinium Cationic Surlactanl5 as Emulslrlers for Oil-In- WaterEmulsions, S. Pegiadoc-Koemtjopouloue. E. Tsatsaroni. and M. Mylona.Laboratory of Organic Chemical Technology, DepilI1m~nt of Chemistry.University or Tbessaloniki. 540 06 Tbessatoniki. Greece.

Pyrimidinium cationic surfactants with 13-17 carbon atoms in thehydmphobe were used as emulsifiers for oil-in-water (heptane/water)emulsions at concentrations near the critical micelle concentrations.Interfacial tensions of the emulsifier solutions in water against heptanewere measured, Drop size distributions of the emulsions were determinedat different times using microscopic tcchniques. and the rate of coates-

cence was calculated. The structure having 16 carbon atoms in the alkylchain had eoeiescerce rates lower than the other Structures. including twoconventional C-16 cauonics used as controls.JSD f. 499-502 (1998).

Enzymatic Preparanen of PoIyethJlene GI,.rol Esters of Castor OilFlilly Acids and Their 5url~Adh'e Properties. M. Ghosh and O.K.Bhanacharyya·. Department of Chemical Technology, Oil TechnologyDivision, Calcuua University. Calcuua - 700 009, India.

This Sludy concerns the preparation and evalLllllion of nonionic surfac-tants prepared from polyethylene glycol (PEG) esters of castor oil fauyacid, a source of hydroxy falty acid. A lipase-catalyzed esrerifkauon reac-tion has been employed to prepare PEG CSlCB of hydroxy acid to ever-come probl~ms associated with chemical processes. Castor oil fatty acid(85'l> ricinoleic acid) was mixed with PEG of different molecular weightRhi:tmrucor m;~he;lipase was added as catalyst (I~ l~v~l) and the reac-tion was continued at 60°C under 2 mm Hg pressure for 360 min.Conversion of PEG to esters was in the range of 86--94%. depending onthe molecular size of PEG. The products were isolated and examined forsurfuce activity by surface tension measurement. Surface tension valuesmeasured III 25°C were lloout36-37 dynes/cm.JSD I, 503-505 (1998).

Mixed Micelles of Cationic Surfllclllnts and Bile Acid Salts InAqueous Media. Alex George, Sambhav vora. Arti Dogra. HemangiDesai, ond Pratap Bahadur·, Department of Chemistry, South GujaratUniversity, Surut 395 007,lndia.

Critical micelle concentrations of cetyltrimerhyl-ammonium-p-toluene sulfonate (CTAT) and cetylpyridinium chloride (CPC) withsodium chelate (NaC) and sodium deoxycholate (NaDC) were deter-mined in aqueous solutions by surface tension measurements.Interaction parameters and mole fraction of the components in mixedmicelles were estimated using Rubingh's thc()ry. Strong interaction wasobserved for each mixed system. a common feature shown by anion-ic-cationic mixtures. Dramatic effects on the viscosities of thesecationic surfactant-bile salt mixtures were seen. and were mark~dlydependent upon the counterion of the cationic surfaclIIDt and the natureof bile salts, Mtceues are small and spherical for cationic surfectams inthe presence of NaC. Micelle growth was seen for CPC in the presenceof NaDC by an increase in viscosity, but a CTAT solution sho ....ed anopposite effect on addition of NaDC, Conductance results supportedthis view. Different behavior of the t....o bile salts is e~plained on thebasis of their orientation in cationic micelles.JSD I. 507-514 (1998).

Uae of Low-Temperature Dirrerentlal Scanning Calurimetry forDerermtnattun of Ethylene Oxtde Conlenl in Some NonionlcSurlilclants, V. Mohan Rae". S. Uma, C.O. Gajelli, and Ravi Y. Kelkar,ICllndia R&T Centre. Thane-40060l. Maharashtra, India.

Low-temperature differential scanning calorimetry studies onethoxylates of hydrogenated castor oil and 12·hydroxysteanc acid showendothermic transformations that could be ascribed to melting of ethyl-ene oxide (EO) components of the surfactant molecule. The ethoxyra-tion process also results in formation of free polyethylene glycol(PEG). Separarton of free PEG followed by area under the curve mea-surements enabled estimation of EO content of the product formed duroing manufacture. The melting endotherm provided additional informa-tion on the chain-length distribution of polyo.yethylene units in thesurfactant.JSI)I, 515-517 (1998).

Quick Identincation of Pollterephthalate In Laundry Detergents bySlmulhlncous Pyrolysis Melhylallon-Gas ChromalographyfMassSpedrometry. Toshihiko Uchiyama and Akihiko Kawauchl'". Procter &Gamble Asia, Research and Developm~nt Department. Kobe TechnicalCenter, Kobe 658-0032. Japan.

This report summarizes Tmthod de~elopment for the identification ofpolyterephehalares using simultaneous pyrolysis methytadon-gas chro-matography with mass spectrometry. Ground detergent products aredirectly pyrolyzcd together with the methylation reagent tetramethylam-monium h)'droxide. Key fragments separated \';n gas chromatography arcdetected by II mass selective detector. Tl1ICe levels of polyrereptahalates in

INFORM, Vol, 9, I)(). II (November 1998)

1098

ABSTRACTS FROM AOCS JOURNALS

laundry delergent products wen: identified within 20 min without interfer-ence from surfactants Of OIlier organics. Detection limit was 0.05'1. byweight in product.ISD I, 519-522 (l998).

Thnlng the PoIJdispersity of Alcohol Elhoxylale!l for EnhaRCtil OilySoli Removal, Salish K. Ooete, Hindustan Lever Research Centre.Mumbai 400 099, India..

Commen:ially available alkyl alcohol clhoxylalcs have Dbroad distri-bution of ethylene oxide (EO) units and also a somewhat narrower distri·bulion of alkyl chain length. Gcnenl1y. the purer the surfactant sample(narrower distribution), the better is its detergency performance. anddetergency peaks al the phase inversion temperature (pm for a given oil.However. in real detergency processes Ihis may not hold true since soilsare typically mixtures of several oily components, and temperarure varia-lions are significant. Therefore, if a pclydlspersity index (PDI) of cllloxy-teres is defined as the ratio of weight average EO moles to number aver-age EO moles in the sample, then lt is conceivable that an optimal POImlgtu be obtained. We compared the detergency of nexececane for pen-methylene glycol monododecyl alcohol (C12E05) samples in a bread POIrange, using an oil-soluble dye. While detergency at 55°C (PIT of hexade-cane with C12E05) decreases monotonically with iocreasing POI. aver-IIge detergency over a 20°C temperature range around the PIT tends toshow a maximum at POI of CIl. 1.1 (narrow-range ethcxylate). Similarly,for a mixture of undecanezhexadecanerterracosane (30:50:20 w/w/w) forwhich the average PIT is approximately the same as that of hexedecane,detergency lit 55"C shows a maximum as a function of POI at a value of-1.31 (broad-range erhoxylate). All detergency results are in generalagreement with the reverse trends in oiVwater interfacial tension and sug-gest that. having decided the optimal EO moles for a given applicationbased on PIT. one can further improve the performance of alcohol ethoxy-teres in real detergency processes by tuning their polydispen.ily.JSD J. 539-545 (l99g).

Prnenting Disc:oloration or Squalene·Soiled Colton Fabrics withAntioxidanl!i. Yong-Seung Chi and S. Kay Obendori". Department ofTextiles and Apparel. Cornell University. Ithaca.. New York. 14g53.

Removal of discoloration caused by aged oily !!Oilsis difficult becauseoily soils undergo autoxidation, which results in polymerization and for-mation of chromophores. U!iCof antioxidants and II reducing agent wasinvestigated for their impact on appearance retention and soil removal.The effect of a reducing agent, sodium dithionitc, on the removal of agedsqualene from COlton fabrics was studled as II pretreatment to laundering,which enhanced the removal of squalene as well as whiteness restoration.Increases in treatment concentration lind time increased color removal.However. no significant increase was found in oil removal, suggestingthat the role of the reducing agent is mllinly a reductive bleaching action.Thus. the color will probably reverse by oxidation over time making thisapproach II not-so-promising laundry treetmern. As a method of prevent-ing discoloration of oily soiled rexrue materials. antioxidants Irgano~·1010. I-butyillydro~yanisole and a-tocopherol were examined; they werefound to be effective antiexidams for thi! purpose by prevenung the dis-coloration of squalene upon aging. With irgarlO~· 1010. this preventionoccurred without dccrcasill8 the detergency of the oil. Most importantly.these antioxidant!; either did not stain the subslrate or showed very lowlevels of staining upon usage. The biggest barrier to applying antioxidant!;on textiles is their hydmpbobic nature. A search for water-soluble antioxi-dant!; with nonstaining and good o ..idaliOf1 inhibiting properties is neccs-wy.JSD I. 523--521 (1998).

Gemini Surractaots. Milton J. Rosena .• and David J. Tncyb.aSurfacwlI Research rnsurue, Bl"I)I)k:lynCollege of the City University ofNew York. Brooklyn. New York 11210, and bSurfactants andPerformance Ingredients. Rl"Iodia. inc .• Cnlllbury. New Jersey 08512-1500.

lllc literature. including patents, describing the emerging area of gem·ini SUrfacWlIs is reviewed, Tbe differences in suuclUlVproperty relaliOf1-ships between gemini and comparable ccnvenucnal surfactants aredc$cribcd and discussed in tenns of their predicted performance proper.tics. Supportive performance data are enumerated.JSD I, 541-554(1998).

The Effect of Branching and UnsaturaUon upon Some Prope:rtifs ofPoIyox,-ethyle:nt GlyCGl Dicsters, Anthony J. O·Le:nick. Jr.· and JeffreyK. PaO;inson. Lambent Technologies Inc .. NOTCTO$5.Georgia.

Fatty acid dicstcrs based upon poIYOliycthy1enc: glycol (PEG) dicstCfSfind applkations in many diverse segments of the chemical industry. PEGdlesters contain hoth a water-soluble and an oil-$Oluble portiOf1. resultingin a surfacc-aclive product. 1besc 5urfactants Clihibit emulsification pr0p-ernes. A study of PEG diCSlers was undertaken to determine the effect ofthe following variables in the Iany portion of the molecule: (i) number ofcarbon atoms present. (ii) bmnching or lack of bmnching. and (iii) pres-ence of unsaturarion. The objective was to compare liter point. solubilitiesand emulsification properties of various PEG·600 based diesters that weresynthesizeu using high-purity linear saturated. Guerbet-branched. andunsaturated acids. Included in the test was n series of esters based uponmeadowfoam oil, a high-molecular-weight unsuturute(i oil.JSD I, 529-532 (1998).

The Role or Enz}"mes in Modern Detergency. Hans Scjr Olsen· and PerFalboh. Enzyme Development & Application. Enzyme Business, NovoNordisk AIS. DK-2880 Bagsvaerd. Denmark.

Enzymes have effectively assisted the development and improvementof modem household and industrial detergents. The major classes ofdetergent enzymes-proteases, hpases. amylases. and celfclases-ceecnprovide specific benefits for application in laundry and automatic dlsh-washing. Historically. proteases were fint 10 be used extensively in laun-dry detergents. In addition 10 raising the level of cleaning. they have alsoprovided environmental benefits by reducing energy consumption throughshorter washing limes, lower washing temperatures. and reduced waterconsumption. Today proreases arc joined by lipases and amylases inimproving detergent efficacy especially for household laurK!ering at lowertemperatures and. in industrial cleaning operations. at lower pH levels.Cellulases contribute to overall fabric care by rejuvenating or maint.ainingthe new appearance of washed garments. Enzymes are produced by fer-ment.ation technologies that utili~ renewable resources.JSD I. 555--561 (1998).

Chlll'1lcterisUc Properties of CUlling Fluld Addltlycs ~rived from theReaction Products of lIydroxyl .'lIlIy Acids with Some AcidAnhydrides. Hideyuki Tomoda'", Yasuhiro Sugimoto". Yumiko Tania.and Shoji WaUlnab&··. ClNEOS Central Re!iCarch Laboratory, Shiga-ken,Japan 520-32. and bOepartment of Applied Cherntsvy, Faculty ofEngineering. Chih3 University, Chiba. Japan 263.

Several adduCIS were prepared from the thermal reaction of hydroliylfatly acids (ricinoleic acid oligomers. 12-hydroliyStcaric acid oligomen,oleyl alcohol. dehydrated castor oil fauy acids. and dimer acid) with male-ic anhydride and screened as water-soluble cutting fluids. For example.aqllCOUS solutions of triethanolamine 5&IU with the products of ricinoleicacid oligomen. 12-hydro ..y'stcar1C acid dimer. and 12-hydro~ystearic acidhexamer soowed good antirust properties for water-based cutting fluids.Various half esters of hydroliyl fatty compounds with acid anhydrideswere prepared. Aqueous $OIuti0f15of triethanolamine salts ofha1f esters ofmaleic anhydride and succinic anhydride and phthalic anhydride withhydroxyl Iarty acids gave good antirust arK!anliwcar properties for water-based cutting fluids.JSD J. 533-531 (1998).

INFORM, Vol. 9, no. 11 (November 1998)