Cottonseed as Protein, Moving Up the Food Chain

by Alex Owre

The white lint that is spun into cotton yarn constitutes roughly a quarter of the raw plant matter sucked into a cotton stripper. Over the years, U.S. producers have learned to squeeze maximum value out the rest, especially the seeds. For every pound of fiber, 1.6 pounds of seed

are produced. Once considered garbage and dumped in streams, cottonseed has long been used as cattle feed, fertilizer, and in countless

industrial applications.

Cottonseed oil comprises about 16% of a seed, by  weight; is a well-known ingredient in many processed snack foods; and is the most

valuable cottonseed product. Current EPA regulations classify it as safe for human consumption after it has been refined to remove volatile compounds such as monoglycerides, some pigments, free fatty acids,

fatty oxidation products, pesticide residues and other undesirable compounds.1

Once most of the oil has been removed, the meal, the second most valuable product of cottonseed, is used principally as livestock feed.

Constituting nearly half of a seed’s weight, the meal contains 23% of a high biological-value protein.

Today, nearly 10% of U.S.-produced meal goes to fish farms, where some species thrive on it. Fish farmers praise it as a cheap, highly

nutritious alternative to fish meal, which is composed primarily of wild-caught marine species, the price of which continues to climb as natural

fish stocks dwindle.

In October, the National Organic Standards Board voted to consider developing organic standards for some farm-raised fish species, while unanimously voting against creating national organic standards for wild-caught fish. Some argue that this could put aquaculturists at a

disadvantage to the beef and poultry industries, which are now eligible for organic labeling.

But cottonseed might provide a loophole. In a recent study funded by the National Cottonseed Products Association and the Cotton

Foundation, Ohio State University researchers replaced fish meal protein with cottonseed meal protein in up to 100% of the diet of

rainbow trout (“Plant-Based Meal Paves Way for "Organically-Grown" Fish,†� OSU Extension). The growth of the fish was unaffected

by the switch, so the researchers suggest that cottonseed meal could replace fish meal as the main protein source of species such as trout,

making them eligible for organic labeling.

Most fish and other non-ruminant animals, including humans, cannot eat cottonseed because it contains a toxin called gossypol. When eaten

by people, this polyphenolic anti-nutrient damages the heart and liver.

For years, scientists have tried to breed cotton with gossypol levels safe for consumption. In the 1950s they succeeded, but because the toxin was

missing from leaves as well as seeds, the plants proved defenseless against pests. But last November – via a new technique called RNA

interference, or RNAi, a gene-silencing mechanism for which its discoverers Andrew Fire and Craig Mello won the 2006 Nobel Prize for Medicine – researchers at the Texas Agricultural Experiment Station succeeded in lowering the gossypol level in seeds while sparing the rest

of the plant.

The result of this experimentation (partially funded by Cotton Incorporated) is being hailed by the cotton industry and

biotechnologists as a breakthrough in the struggle against world hunger. According to Dr. Keerti Rathore2, one of the Texas researchers, the current level of 44 million tons of cottonseed produced globally each

year, containing 22% high-quality protein, could feed 500 million people. Studies in animals, including humans, using gossypol-free,

glandless cottonseed flour, have shown that cottonseed protein promotes growth, weight gain, and a positive nitrogen balance (less N is excreted

through urine, feces and sweat than is taken in). Researchers are already experimenting with lowering gossypol levels in indigenous

African cotton strains, as well as employing RNAi technology on other crops with toxic components, such as fava beans.

Solution to Hunger … or Diversion?

Industry estimates put the time-to-market for low-gossypol cotton at 10 years. Scientists maintain that cotton farmers in poor countries will

doubly benefit from a crop that can be sold for food (or be eaten directly) and clothing. Supporters of genetic engineering hope that the prospect of “feeding the world†� with cotton will win over skeptics

and change policies of those poor countries that are, so far, resisting the pressure to give in to genetically engineered (GE) crops.

Environmentalists remain wary, citing the example of golden rice, genetically engineered to contain vitamin A but requiring consumption

of huge amounts to derive any benefit.  (Furthermore, fields that are not clean cultivated usually contain edible greens that are rich in vitamin A

and other nutrienets.)  Edible-seed variety cotton will not solve the problems of GE foods, environmentalists maintain, but will exacerbate them. Zachary Makanya, in his excellent article for Seedling Magazine

(August 2004, www.grain.org/seedling/?id=294)), explains why GE crops have no place in African agriculture (a target market for low-

gossypol cotton). GE crops – 1. will contaminate non-GE crops; co-existence is not possible;

2. will foster dependence on a corporate seed supply; 3. will usher in “Terminator†� and “Traitor†� technologies;

4. will increase the use of chemicals; 5. are patented;

6. favor industrial agricultural systems; 7. threaten organic and sustainable farming;

8. require biosafety systems unrealistic for African countries; 9. will not reduce hunger in Africa;

10.will not resolve problems with pests; 11.will encourage arbitrary destruction of biodiversity;

12.are a threat to human health. 

Says Sue Mayer, director of GeneWatch UK: “Poverty and hunger are complex problems caused by bad government, poor economies and

war. It is not just a matter of finding a new wonder plant.†�

Concerning cottonseed as fish meal, the problem of crashing ocean populations will put into perspective any satisfaction we derive from

fish that will eat, and even thrive, on cotton’s protein. As fish meal, cottonseed might open new channels of discussion around organic food labeling, but as human food, is the science of edible cottonseed a red-

herring in the real struggle to feed the world’s poor?

1. Environmental Protection Agency40 CFR Part 185 [OPP-300335A; FRL-5357-7]

Revocation of Pesticide Food Additive Regulations

2. http://www.pnas.org/cgi/content/abstract/103/48/18054Engineering cottonseed for use in human nutrition by tissue-specific

reduction of toxic gossypol Ganesan Sunilkumar, LeAnne M. Campbell, Lorraine Puckhaber ,

Robert D. Stipanovic , and Keerti S. Rathore.

Read Alex Owre's article about cotton from a previous issue:

King Cotton and the Wal-Mart Shopper (Winter 2006-2007)

Research Project: New and Expanded Uses of Oilseed Products and By-Products

Location: Commodity Utilization Research

Title: COTTONSEED EXTRACTION WITH MIXTURES OF ACETONE AND HEXANE

Authors Kuk, Myong

Tetlow, R

Dowd, Michael Submitted to: Journal of the American Oil

Chemists' Society Publication Type: Peer Reviewed Journal Publication Acceptance Date: February 15, 2005 Publication Date: May 1, 2005 Citation: Kuk, M.S., Tetlow, R., Dowd, M.K. 2005. Cottonseed extraction with mixtures of acetone and hexane. Journal of the American Oil Chemists' Society. 82(8):609-612.

    

Project Team

Dowd, Michael - Mike

Kuk, Myong - Sam

Dailey, Oliver

Klasson, Kjell

 

Publications

   Publications

 

Related National Programs

Interpretive Summary: Cottonseed meal and oil are produced from cottonseed by solvent extraction. Although cottonseed meal is valuable as animal feed, the use of cottonseed meal is limited by the toxicity of gossypol. Commercial hexane, currently used for extracting oil from cottonseed, does not efficiently extract gossypol. Hence, the cottonseed meal produced by extraction with commercial hexane has a small amount of gossypol. In comparison, pure acetone is known to efficiently extract oil and gossypol from cottonseed. Although the cottonseed meal produced by pure acetone contains a negligible amount of gossypol, the meal has a detrimental odor, known as "catty odor." SRRC scientists found that adding small amounts of acetone (up to 25%) to hexane significantly increased extraction of gossypol from cottonseed flakes. The SRRC scientists also found that a mixture of acetone/hexane with 10% acetone can be used to efficiently extract oil and gossypol from cottonseed, and produce cottonseed meal without "catty odor." The research directly benefits the U.S. farmers who grow cotton, and indirectly the oilseed processing industry which are involved in producing cottonseed meal and edible oil.

Technical Abstract: Cottonseed flakes were extracted with mixtures of n-hexane and acetone with the concentration of acetone varying between 10 and 75%. Adding small amounts of acetone (<25%) to n-hexane has significantly increased the extraction of free and total gossypol from cottonseed flakes. Sensory testing detected no difference in the odor of cottonseed meals of those produced either by extraction with 100% n-hexane or by extraction with a 10/90(v/v)% of

 

Quality and Utilization of Agricultural Products (306)

 

Related Projects

   Derivatization of Gossypol for Value-Added Utilization

   Value Added Uses of Cottonseed Products

 

acetone/hexane. More than 80% the free gossypol was removed by the 10/90% acetone/hexane extraction mixture. A solvent mixture containing 25% acetone removed nearly 90% of the free gossypol that was removed by extraction with pure acetone and had only a minimum increase in meal odor. In contrast, cottonseed meals produced by extraction with pure acetone had a much higher odor intensity. The composition of the cottonseed crude oil was insignificantly affected by the acetone concentration of the extraction solvent.

Cottonseed extraction with a new solvent system: Isohexane and alcohol mixtures

Authors: Kuk, M.1; Hron, R.Source: Journal of the American Oil Chemists' Society, Volume 75, Number 8, August 1998 , pp. 927-930(4)Publisher: Springer

< previous article next article > | view table of contents

  

Key: - Free Content - New Content - Subscribed Content - Free Trial Content

 Abstract:

A solvent system, consisting of isohexane and 5 to 25% alcohol, either ethanol (EtOH) or isopropyl alcohol (IPA), was tested for extracting gossypol and oil from cottonseed. The test results indicate that this new solvent system not only is effective in removing free and total gossypol but also is as efficient as n-hexane when extracting oil. The amino acid analysis of cottonseed meal, produced by the new solvent system, is similar to that produced by commercial n-hexane. Present commercial cottonseed extraction and downstream processing of cottonseed oil refining may need little change to adopt this new solvent system. This new solvent system may lead to a solution to the gossypol problem of cottonseed extraction.

Keywords: Cottonseed; extraction; free gossypol; meal; new solvent; oil total gossypol Document Type: Research article DOI: 10.1007/s11746-998-0268-4Affiliations: 1: Email: mskuk@nola.srrc.usda.gov

Titre du document / Document titleEthanol extraction of oil, gossypol and aflatoxin from cottonseed

Auteur(s) / Author(s)HRON R. J. ; KUK M. S. ; ABRAHAM G. ; WAN P. J. ;

Affiliation(s) du ou des auteurs / Author(s) Affiliation(s)ARS, SRRC, New Orleans LA 70719, ETATS-UNIS

Résumé / AbstractCommercial processing of cottonseed requires hexane to extract and recover edible oil. Gossypol and aflatoxin are not removed from extracted meals. A bench-top extraction process with 95% (vol/vol) aqueous ethanol (EtOH) solvent has been developed that extracts all three of the above materials with a much less volatile solvent. In this process, cottonseed is pretreated and extracted with ambient 95% EtOH to remove gossypol and then extracted with hot 95% EtOH to extract oil and aflatoxin. Membranes and adsorption columns are used to purify the various extract streams, so that they can be recycled directly. A representative extracted meal contained a total gossypol content of 0.47% (a 70% reduction) and 3 ppb aflatoxin (a 95% reduction)

Revue / Journal TitleJournal of the American Oil Chemists' Society  (J. Am. Oil Chem. Soc.) ISSN 0003-021X 

Source / Source1994, vol. 71, no4, pp. 417-421 (28 ref.)

Langue / LanguageAnglais

Editeur / PublisherSpringer, Heidelberg, ALLEMAGNE (1947) (Revue)

Mots-clés anglais / English KeywordsCottonseed meal ; Cottonseed oil ; Solvent extraction ; Ethanol ; Chemical contamination ; Aflatoxin ; Gossypol ;

Mots-clés français / French KeywordsFarine coton ; Huile coton ; Extraction solvant ; Ethanol ; Contamination chimique ; Aflatoxine ; Gossypol ;

Mots-clés espagnols / Spanish KeywordsHarina algodón(semilla) ; Aceite algodón ; Extracción solvente ; Etanol ; Contaminación química ; Aflatoxina ; Gosipol ;

Localisation / LocationINIST-CNRS, Cote INIST : 204, 35400004538725.0120

Copyright 2007 INIST-CNRS. All rights reserved

---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Title:Extraction of gossypol from cottonseed Document Type and Number:United States Patent 5112637 Link to this page:http://www.freepatentsonline.com/5112637.html Abstract:The present invention is drawn to a process for extraction of gossypol for cottonseed using a solvent solution which includes: (a) a water miscible organic solvent; (b) water; and (c) an acid which is strong enough to prevent binding of gossypol to cottonseed protein but which is not so strong as to hydrolyze a substantial portion of the cottonseed protein. The present invention also includes cotton seed meals of reduced gossypol content (and optionally reduced aflatoxin and/or fat content) produced by the aforementioned extraction.

Inventors:Hron Sr., Robert J. (New Orleans, LA) Abraham, George (Metairie, LA) Kuk, Myong S. (Metairie, LA) Fisher, Gordon S. (Metairie, LA) Application Number:07/608786 Filing Date:11/05/1990 Publication Date:05/12/1992 View Patent Images:Images are available in PDF form when logged in. To view PDFs, Login  or  Create Account (Free!)

Referenced by:View patents that cite this patent Export Citation:Click for automatic bibliography generation Assignee:Agriculture US. (US) Primary Class:426/629 Other Classes:426/430, 554/13, 426/486, 426/331, 554/11 International Classes:A23K1/14; A23L1/211; C11B1/10; C11B1/00; A23B9/16 Field of Search:426/486, 426/629, 426/656, 426/622, 426/430, 426/331, 260/412.4 US Patent References:

2615808October, 1952

Rice 260/412.4Preparation of cottonseed meal

2950198August, 1960

King et al. 426/417Production of cottonseed meal of improved quality

3062876November, 1962

Pons et al. 260/520Process for recovery of gossypol from cottonseed gums

3432529March, 1969

Depmer 260/412.4

METHOD AND APPARATUS FOR THE EXTRACTION OF OIL FROM COTTONSEED

3557168January, 1971

Don, Jr. et al.

260/412

3615657October, 1971

Gastrock 426/486

PROCESS FOR PRODUCING COTTONSEED PROTEIN CONCENTRATE

3941764March, 1976

Hensarling 426/656Use of acidic hexane to process oil seeds for protein and oil

3972861August, 1976

Gardner 426/656Process for producing an edible cottonseed protein concentrate

4072671 February, Sodini 426/634 Method for extracting

1978phenols and oligosaccharides from vegetable tissues

4084007 April, 1978 Hipp 426/430Method of producing edible meal from cottonseed

4139646February, 1979

Gastrock 426/430Process for treating cottonseed meats

4148928 April, 1979 Sodini et al. 426/430

Method for the extraction of undesirable and/or toxic glucosidic compound from vegetables

4201709 May, 1980 Kadan 426/430Process for producing a low gossypol protein product from glanded cottonseed

4219469August, 1980

Kadan et al.

260/123.5Extraction of cottonseed and concentrates to improve the color of protein isolate

4359417November, 1982

Karnofsky et al.

260/235

Process for extracting oleaginous seed materials particularly cottonseed with aqueous alcohol

4546004October, 1985

Rhee 426/629Method of producing low-gossypol cottonseed protein material

4747979 May, 1988 Gimber 260/412.4Removal of toxins from cottonseed

Other References:Canella et al, Journ. of Food Science, 42:1218-1219, 1977. Abov-Donia et al, "High-Performance Liquid . . . ", Journal of Chrom. 206 (1981) 606-610. English Language abstract of German Offen 2,606,961, 9 Sep. 1976. English Language abstract of Spanish patent 445,653, 01 Jun. 1977. Abstract of: M. Canella et al, "Functional Properties . . . " Riv. Ital. Sostanze Grasse 1977, 54(2), 73-6. Abstract of: G. Sodini et al, "Effect of . . . " Riv. Sci Technol. Alimenti Nutr. UM 1976, 6(4), 219-21. Abstract of German Offen 2,631,695, 26 Jan. 1977. Primary Examiner:Paden, Carolyn Attorney, Agent or Firm:

Sadowski, David R. Silverstein, Howard M. Claims:What is claimed is:

1. A process for extraction of gossypol from cottonseed, which process comprises:

(a) contacting cottonseed with a solvent solution comprised of: (i) a water miscible organic solvent; (ii) water, and; (iii) an acid which is characterized as being strong enough to prevent binding of gossypol to cottonseed protein, but not so strong that it will hydrolyze a substantial portion of said cottonseed protein; under conditions providing extraction of gossypol from said cottonseed by said solvent solution, thereby producing cottonseed meal of reduced gossypol content and solvent solution having gossypol therein; and

(b) separating said cottonseed meal of reduced gossypol content from said solvent solution having gossypol therein.

2. The process of claim 1 wherein said water miscible organic solvent is selected from the group consisting of alcohols, esters, ethers, nitriles and mixtures thereof.

3. The process of claim 2 wherein said water miscible solvent is a C1 to C3 monohydric alcohol.

4. The process of claim 3 wherein said water miscible alcohol is ethanol.

5. The process of claim 3 wherein said step of contacting is carried out with a weight ratio of solvent solution to cottonseed of from about 15 to 1 to about 1 to 1.

6. The process of claim 1 wherein said cottonseed meal of reduced gossypol content is rinsed with fresh solvent after said step of contacting.

7. The process of claim 6 wherein said fresh solvent includes a water

miscible organic solvent selected from the group consisting of alcohols, esters, ethers, nitriles and mixtures thereof.

8. The process of claim 1 wherein said solvent solution has a pH of from about 2 to about 5.

9. The process of claim 8 wherein said solvent solution has a pH of from about 2 to about 4.

10. The process of claim 1 wherein said acid is a tribasic inorganic or organic acid.

11. The process of claim 10 wherein said acid is selected from the group consisting of citric acid, ascorbic acid, phosphoric acid, and mixtures thereof.

12. The process of claim 1 wherein said step of contacting is carried out with a weight ratio of solvent solution to cottonseed of from about 1 to 1 to about 1 to 1.

13. The process of claim 1 wherein said cottonseed and said solvent solution, contain a total of from about 2 to about 32 wt. % water.

14. The process of claim 13 wherein said cottonseed and said solvent solution, contain a total of from about 4 to about 12 wt. % water.

15. A cottonseed meal of reduced gossypol content produced by the process of claim 13.

16. The process of claim 1 wherein said step of contacting is carried out at a temperature from about 50° C. to about 90° C.

17. The process of claim 1 which is practiced at pressures up to about 60 psig and temperatures up to about 130° C.

18. The process of claim 1 which is practices at pressures of about 3 to about 10 psig and temperatures from about 80° C. to about 90° C.

19. A cottonseed meal of reduced gossypol content produced by the process of claim 18.

20. The process of claim 1 wherein said step of contacting removes aflatoxins from said cottonseed.

21. A cottonseed meal of reduced gossypol and reduced aflatoxin content produced by the process of claim 20.

22. The process of claim 1 wherein said cottonseed is full fat, and said step of contacting extracts fat from said cottonseed.

23. A cottonseed meal of reduced gossypol and reduced fat content produced by the process of claim 22.

24. The process of claim 1 wherein said cottonseed is wholly or partially defatted prior to said step of contacting.

25. A cottonseed meal of reduced gossypol content produced by the process of claim 1.

26. A cottonseed meal of reduced gossypol, aflatoxin and fat content produced by the process of claim 1.

Description:

FIELD OF THE INVENTION

This invention relates to a solvent extraction process for removing gossypol (a toxic pigment) from cottonseed. The extraction is conducted with a solvent solution comprised of: a water miscible organic solvent, water and an acid which is strong enough to prevent gossypol from binding to cottonseed protein, but not so strong that it hydrolyses a substantial amount of the cottonseed protein.

BACKGROUND OF THE INVENTION

Unlike other commercial oilseeds, cottonseed contains a toxic pigment, gossypol, which prevents it from being a feed for animals, other than those that have a rumen. That is, while some whole cottonseed is fed to mature ruminants, most of it is separated into oil and meal, typically by

solvent extraction using hexane. As used herein, cottonseed meal, or flour, refers to the whole residue remaining after most of the oil has been removed. Before the oil and meal can be used as a food source, the gossypol must be removed or deactivated. In addition, unfavorable growing, harvesting, or storage conditions can cause cottonseed to mold and become contaminated with a mold metabolite aflatoxin, which, because it is carcinogenic, must be removed, or destroyed. The presence of such toxic components prevents cottonseed from reaching its full potential as a food source, especially in countries that grow cotton but not soybeans. In the intact cottonseed, the gossypol is concentrated in glands that are covered with a hydrophilic coating, which keeps the gossypol from coming into contact with other components of the seed. Originally, gossypol was deactivated by pressing, or expelling, the oil out of moist seeds at relatively high temperatures, such as at temperatures from about 110° to 130° C. Under these conditions, the glands are ruptured by hot moisture, releasing gossypol. Most of the gossypol reacts with protein, thereby forming bound gossypol, which is insoluble. The rest reacts with phospholipids and other low molecular weight components of the seed to give products that are soluble in oil and other organic solvents, as is any unreacted gossypol. The gossypol in these soluble products is referred to as free gossypol. Total gossypol is the sum of bound gossypol and free gossypol. Total gossypol content of meals made by such a process are typically from about 0.7 to 1.0 wt. %. While binding to protein is advantageous in that it acts to detoxify the gossypol, it is disadvantageous because it reduces the nutritive value of the meal by reducing the available lysine content.

Currently, separation is done by expression, or by extraction of the oil from flaked kernels at elevated temperatures with a solvent such as hexane, or a combination of expression and extraction. The most common method used today is solvent extraction, but unless a separate moist heating preconditioning step is included, meals produced by this method will contain unruptured glands and excessive amounts of free gossypol. Furthermore, it is well known that adverse physiological effects can occur with some meals containing high total gossypol, even though free gossypol is within acceptable limits.

Hence, it has long been recognized that a process is needed that could reduce the total gossypol of cottonseed meal by removing gossypol instead of binding it to protein. Various processes have been developed

in an attempt to accomplish this. For example, multistep processes in which both the oil and gossypol are extracted with different solvents, in different steps, are known. For example, U.S. Pat. No. 4,359,417, teaches a two step process comprising first extracting cottonseed flakes with an 85% aqueous ethanol solution at about 110° F., which removes some of the gossypol with the remainder becoming bound to the meal. This is followed by a second extraction but with a 95% ethanol solution at 175° F., which removes the oil. Although such a process has merit, it can do no better than produce a meal which still contains from 0.29 to 0.45 wt. % total gossypol and 0.019 to 0.045 wt. % free gossypol.

Another reference, Canella and Sodini (Journal of Food Science, 42:1218-1219 (1977)), discloses a method wherein hexane extraction of raw cottonseed at 25° C. is used to produce a cottonseed meal, followed by room temperature extraction with n-butanol containing HCl at carefully controlled pH of about 4.5, in order to obtain a product which contains 0.34 wt. % total and 0.07 wt. % free gossypol. One disadvantage of such a process is that the high boiling point of n-butanol makes its removal from the meal difficult. Further, the one-solvent processes that have been described in the art generally use mixed solvent systems which are not suitable for food use. For example, U.S. Pat. No. 3,557,168 teaches the use of a hexane-acetone mixture and U.S. Pat. No. 2,950,198 (King et al, 8/1960) teaches the use of a hexane-acetone-water mixture. Both of these processes leave residues which produce a strong objectionable catty odor in the meal, thus making them unsuitable for food use. Further, U.S. Pat. No. 4,747,979 teaches the use of a chlorinated hydrocarbon as one component of their mixed solvent, which of course is also unsuitable for food use.

Although other separation processes, such as the liquid cyclone process taught in U.S. Pat. No. 3,615,657 can yield solid products containing less than about 0.3 wt. % total gossypol from glanded seed, such low gossypol fractions account for only about 50% of the total meal. The remaining fraction contains relatively high total gossypol concentrations.

Also, U.S. Pat. No. 4,219,469, teaches the use of a solvent solution comprised of: a non-polar solvent, such as hexane; a polar solvent, such as ethanol; and a food grade acid, such as citric acid; to obtain protein isolates from cottonseed. The isolates are improved because of their

improved coloration. Gossypol is not significantly removed by the process of this reference.

Furthermore, in conventional processes for producing cottonseed meal, a small amount of the gossypol which is present in the seed, is bound to phospholipids and extracted with the oil. This is in contrast to the major portion which is bound to protein and remains in the meal. Another patent, U.S. Pat. No. 3,062,876 discloses that the soluble bound gossypol can be dissolved in methyethylketone (MEK) and hydrolyzed in the presence of phosphoric acid. It is stressed that MEK be used because the bound gossypol must be soluble in the acidic solution used for hydrolysis.

The potential use of gossypol as a male contraceptive is an added incentive for the need for a process that can separate unmodified gossypol from both cottonseed oil and meal, instead of binding it to the meal. Consequently, there still exists a need in the art for more effective processes for removing gossypol, as well as other non food grade components from cottonseed.

SUMMARY OF THE INVENTION

In accordance with the present invention, there is provided a process for the extraction of gossypol from cottonseed, which process comprises:

(a) contacting cottonseed with a solvent solution comprised of: (i) a water miscible organic solvent; (ii) water; and (iii) an acid which is characterized as being strong enough to prevent binding of the gossypol to the cottonseed protein, but not so strong that it will hydrolyze a substantial portion of the cottonseed protein; under conditions providing extraction of gossypol from said cottonseed by said solvent solution, thereby producing cottonseed meal of reduced gossypol content and solvent solution having gossypol therein; and

(b) separating said cottonseed meal of reduced gossypol content from said solvent solution having gossypol therein.

In a preferred embodiment of the present invention, the water miscible solvent is selected from the water miscible alcohols, esters, ethers, nitriles and mixtures thereof, and is present in a weight ratio of solvent

solution to cottonseed of from about 12 to 1 to about 1 to 1, and the cottonseed is in the form of kernels, flakes or a meal.

In other preferred embodiments of the present invention, the acid present is such that it is able to provide the solvent solution with a pH of from about 2 to about 5.

In yet other preferred embodiments of the present invention, the solvent solution is comprised of about 2 to 12 wt. % water and from about 75 to 95 wt. % solvent and the extraction is conducted at a temperature from about 50° C. up to, but not including, the boiling point of the solvent.

In still further preferred embodiments of the present invention, the water miscible solvent is selected from the group consisting of the C 1 to C 3 monohydric alcohols and the acid is selected from the tribasic acids: citric acid, ascorbic acid, phosphoric acid, and mixtures thereof.

The present invention also includes cottonseed meals of reduced gossypol content (and optionally reduced aflatoxin and/or fat content) produced by the processes of the instant invention. Other aspects, objects and advantages of the present invention will become readily apparent from the ensuing description.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In general, the solvent solution of the present invention contains: a water miscible organic solvent, the aforementioned acid, and water. The water content of the combination of both the cottonseed and the solvent solution should range from about 2 to 32 wt. %, preferably from about 2 to 14 wt. %, and more preferably from about 4 to 12 wt. %. The amount of water required in the solvent solution will be affected by the water already present in the cottonseed. After preparation for extraction, the cottonseed kernels, flakes, or full fat meal, usually contains from about 2 to 14 wt. % water. Preferably, the weight percent of water in the solvent should be at least 12 wt. % minus the wt. % of water in the cottonseed product. The upper limit of water concentration is set by the minimum functional concentration of the other two components, the solvent and the acid, which will be discussed in detail below.

In order to inhibit binding of gossypol without significant hydrolysis of protein, the pH of the solvent solution should be from about 2 to about 5, preferably from about 2 to about 4, and more preferably from about 2 to about 3. Depending on the equivalent weight and pK (negative logarithm of the first dissociation constant of the acid) the effective amount of acid will usually range from about 1 to 20 wt. % acid, preferably from about 2 to 10 wt. % acid. Preferred acids are those having equivalent weights of less than about 80 and a pK of from about 2 to about 4.2. Acetic acid, which has a pK of 4.75, is unsuitable for use herein. Nonlimiting examples of preferred acids, are both organic and inorganic (e.g. tribasic inorganic or organic acids) and include phosphoric, citric, and ascorbic acids, and mixtures thereof. More preferred are phosphoric (eq.wt.=33, pK=2.1) and citric (eq.wt. =64, pK =3.1) acids, which at concentrations of 0.1 to 0.4 molar give pHs from about 3.2 to 2.3. Most preferred are food grades of these acids, so that residual acid in the cottonseed meal or flakes would not preclude approval for food use.

Non-limiting examples of water miscible organic solvents usable in the present invention include: alcohols, esters, ethers, nitriles, and mixtures thereof. Preferred are the water miscible organic solvents. More preferred are the C 1 to C 3 monohydric alcohols, most preferably are those that are suitable for use in food processing, such as ethanol, which is non-toxic, has favorable oil- and acid-solubility, is easy to recover for recycling, and is a standard article of commerce. Maximum concentration of organic solvent in the solvent solution is determined by subtracting the required water and acid concentrations from 100 wt. %, i.e. about 99 wt. % for extraction of cottonseed containing more than 12 wt. % water using the minimum amount of acid. The minimum concentration will depend on the specific organic solvent and is determined by the requirement that both oil and gossypol be soluble in the solvent solution. The minimum will be highest for low extraction temperatures and lowest for extractions carried out under pressure at temperatures above the normal boiling point of the solvent. In general, the solvent solution will contain about 70 to about 98 wt. % organic solvent, preferably about 75 to about 95 wt. %, more preferably about 80 to about 90 wt. %. Most preferred is about 83 to about 92 wt. % ethanol, which corresponds to use of commercial 95 vol. % ethanol to prepare 0.1 to 0.4 molar solutions of citric and phosphoric acid.

The present invention can be practiced in a variety of ways. For example, the extraction can be performed in a batch mode. As in any extraction process, a single equilibration of the cottonseed flakes with the solvent, followed by separation of the two phases, yields a miscella containing extracted oil and gossypol, and a marc consisting of residual flakes saturated with absorbed miscella. In order to remove all of the oil and gossypol, the equilibrium process must be repeated several times with fresh solvent. The number of cycles required will be dependent on such things as the strength of the solvent, the solvent to flakes ratios, the temperature and pressure conditions, and the desired degree of oil and gossypol removal. In general, for maximum removal, from about 5 to 10 cycles may be required using the most preferred solvents at about 78° C. and atmospheric pressure, with about a 3 to 1 wt. ratio of solvent to flakes in the first cycle, and a 2 to 1 wt. ratio in subsequent cycles.

In general, the process of the present invention may be carried out over a wide range of temperatures. This range will generally be from about 50° C. up to about 90° C. It is also understood that the extraction can also be run at elevated temperatures and pressures, preferably up to those pressures which can be safely practiced with the type of equipment used in commercial cottonseed extraction. This pressure can be up to about 60 psig at temperatures up to about 130° C, more preferably from about 3 to about 10 psig, at temperatures of from about 70° C to about 90° C, preferably from about 80° C to about 90° C

The present invention can also be practiced in a continuous process wherein the solvent solution is preferably run countercurrent to the cottonseed and the residence time of the cottonseed, in contact with fresh solvent, will determine the extent of oil and gossypol removal. Such determinations of residence times etc. are within the ordinary skill of those in the art, given the teachings herein, and need not be discussed further. It is preferred to rinse the cottonseed meal of reduced gossypol content (after the step of contacting) With fresh solvent, which may be similar to that used in the extraction but without added acid in order to recover acid absorbed by the cottonseed. Thus, the fresh solvent may include a water miscible organic solvent selected from the group consisting of alcohols, esters, ethers, nitriles and mixtures thereof.

The term cottonseed, as used herein, is meant to include cottonseed in any form. That is, the present invention can be practiced on cottonseed

in any form (e.g. kernels, flakes, meal, full fat, wholly defatted prior to the step of contacting, partially defatted prior to the step of contacting, etc.), although it is preferred not to us whole seed because of the difficulty of achieving an effective extraction. Also, ground kernels present a problem of fines which makes separation of the meal from miscella difficult.

The foregoing detailed description is given merely for purposes of illustration. Modifications and variations may be made therein without departing from the spirit and scope of the invention.

The following examples are presented for illustrative purposes only and are

not to be taken as limiting the scope of the claims hereof.

EXAMPLE 1

Full-fat cottonseed meals, containing 8% moisture, were flaked using conventional flaking rolls set at 0.008 inches. A 300 gram (g) portion of the flakes and a 95 vol. % ethanol solution (800g) were placed in a jacketed, stainless steel, cylindrical extractor (6" diam.×6" deep) fitted with a 12 mesh stainless steel retaining screen at the bottom. Hot (79° C) water was circulated through the jacket. Solvent was recirculated through the flakes at a rate of 1 liter (L)/min for 10 min. Miscella (ca 300 g) was drained from the extractor and the flakes were reextracted under the same conditions using 600 g portions of solvent solution. After the seventh extraction, each extraction being about 10 min in duration, the spent flakes were washed with 650 g of 95 vol. % ethanol to remove acid absorbed by the meal. Spent flakes were allowed to air dry at room temperature (ca 25° C) over night and then oven dried at 1010 C for one hour. They were then ground with a Wiley mill to pass a 20 mesh screen, analyzed for residual lipids, total gossypol, and free gossypol. The solvent solutions were comprised of 0.1 and 0.4M citric acid, prepared using anhydrous citric acid, and 0.1 and 0.34M phosphoric acid, prepared using 85 wt. % orthophosphoric acid, all in 95 vol. % ethanol. For comparison, an extraction of the same lot of flakes was made using 95 vol. % ethanol without tribasic acid. The results are shown in Table I below for full fat flakes which initially contained 26.3 wt. % lipids, 8 wt. % moisture, 1.08 wt. % total gossypol and 1.06 wt. % free gossypol.

TABLE I ______________________________________

wt. % wt. % wt. % RESIDUAL TOTAL FREE SOLVENT LIPIDS GOSSYPOL* GOSSYPOL*

______________________________________

No acid 0.75 1.08 0.08 0.1M citric 1.1 0.40 0.02 0.4M citric 1.1 0.09 0.007 0.1M 0.5 0.27 0.02 phosphoric 0.34M 1.4 0.03 0.005 phosphoric ______________________________________

*Moisture- and oilfree basis. Conventional hexane extraction left 1.46 wt. % total gossypol, of which 0.56 wt. % was free gossypol, in the meal.

This example shows that the present invention provides a u very substantial reduction in the concentration of total gossypol and free gossypol, as compared to extraction with ethanol alone or extraction with hexane.

EXAMPLE 2

As shown in the following Table II below, when cottonseed containing aflatoxin, chiefly aflatoxin B1, is processed as described in Example 1 hereinabove, aflatoxin, as well as gossypol, are removed from the meal.

TABLE II ________________________________________________________ __________________

wt. % ppb wt. % wt. % RESIDUAL B1 TOTAL FREE SOLVENT LIPIDS AFLATOXIN* GOSSYPOL* GOSSYPOL*

________________________________________________________ __________________

None** 26.2 69 1.00 0.91 No Acid 0.94 3.6 0.80 0.01 0.1M citric 0.87 3.8 0.22 0.01 0.4M citric 2.3 3.4 0.09 0.06 0.1M phosphoric

1.1 3.7 0.08 0.01 0.34M phosphoric 5.1 2.9 0.05 0.004 ________________________________________________________ __________________

*Moisture- and oilfree basis. **Unprocessed fullfat flakes; as is basis.

Conventional hexane extraction left 37.5 ppb aflatoxin, 1.24% total-, and 0.84% free- gossypol, all moisture- and oil-free basis by weight, in the meal.

EXAMPLE 3

The process of the instant invention is intended primarily for use on full-fat flakes that contain very little bound gossypol (total minus free); however, as illustrated in this example a significant reduction in total gossypol content of partially defatted or fully defatted meals and other products containing large amounts of bound gossypol can be achieved by extraction with solvents described herein.

A 300 g sample of cottonseed flakes, similar to those used in Example 1, were extracted with 95 vol. % ethanol in a Soxhlet apparatus for 4 hours, which removed most of the oil and converted most of the gossypol from free to bound form. The resulting defatted meal, which contained 6.5 wt. % residual lipids, 1.40 wt. % total gossypol and 0.02 wt. % free gossypol, was extracted three times using 800, 600, and 600 g of acidified 95 vol. % ethanol as indicated in Table III below. Each extraction was at 78° C. for 20 min.

TABLE III ______________________________________

wt. % RE- wt. % wt. % SIDUAL TOTAL FREE LIPIDS* GOSSYPOL* GOSSYPOL*

______________________________________

Starting Material 6.5 1.40 0.02 (i.e. defatted meal) 0.4M citric acid 0.29 0.88 0.12 in 95 vol. %

ethanol 0.34M phosphoric 0.13 0.52 0.09 acid in 95 vol. % ethanol ______________________________________

*Moisture- and oilfree basis.

Journal Article

Isopropanol as a solvent for extraction of cottonseed oil I. Preliminary investigations Journal Journal of the

American Oil Chemists' Society

Publisher Springer Berlin / Heidelberg

ISSN 0003-021X (Print) 1558-9331 (Online)

Issue Volume 24, Number 11 / November, 1947

DOI 10.1007/BF02643518

Pages 370-375

Subject Collection Chemistry and Materials Science

SpringerLink Date Monday, June 11, 2007

Add to marked items Add to shopping cart Add to saved items Permissions & Reprints Recommend this article

W. D. Harris1, F. F. Bishop1, C. M. Lyman2 and R. Helpert1

(1)  Chemical Engineering Department, A. & M. College of Texas, Texas, USA

(2)  Texas Agricultural Experiment Station, A. & M. College of Texas, Texas, USA

Summary  Phase equilibrium data for the system; cottonseed oil-isopropanol-water were determined at 30°C. and compared with data for the system; cottonseed oilethanol-water. The relative phase distribution of fatty acids and cottonseed oil in mixtures with isopropanol and water was studied under varying conditions of water and fatty acid concentrations. These tests showed the fatty acids to be highly concentrated in the alcohol-water phase. Flaked cottonseed meats were extracted in continuous extraction apparatus with 91% isopropanol, 99% isopropanol, and mixtures of commercial hexane and isopropanol. Analytical data on the extractions show that 91% isopropanol is an efficient solvent for extracting active gossypol along with the oil. Rat and swine feeding tests of the isopropanol extracted meal showed it to be highly superior to hydraulic meal as a source of protein. A method was developed for treatment of the cottonseed-isopropanol miscella by liquid-liquid extraction to separate purified oil and fatty acid fractions from other materials in the extract.

References secured to subscribers.

Journal of Food Science

Volume 49 Issue 4 Page 1057-1060, July 1984

To cite this article: E. H. RAHMA, M. S. NARASINGA RAO (1984) Gossypol Removal and Functional Properties of Protein Produced by Extraction of Glanded Cottonseed with Different Solvents Journal of Food Science 49 (4), 1057–1060. doi:10.1111/j.1365-2621.1984.tb10391.x

Prev Article Next Article Abstract

Gossypol Removal and Functional Properties of Protein Produced by Extraction of Glanded Cottonseed with Different Solvents

E. H. RAHMA11 Author Narasinga Rao (to whom inquiries should be directed) is Project Coordinator, Protein Technology Discipline, Central Food Technological Research Institute, Mysore — 570 013, India. Author Rahma is a United Nations University Fellow; present address: Food Science & Technology Dept., Faculty of Agriculture, Univ. of Monoufeia, Shibin-EI-Kom, Egypt. and

M. S. NARASINGA RAO11 Author Narasinga Rao (to whom inquiries should be directed) is Project Coordinator, Protein Technology Discipline, Central Food Technological Research Institute, Mysore — 570 013, India. Author Rahma is a United Nations University Fellow; present address: Food Science & Technology Dept., Faculty of Agriculture, Univ. of Monoufeia, Shibin-EI-Kom, Egypt.

1Author Narasinga Rao (to whom inquiries should be directed) is Project Coordinator, Protein Technology Discipline, Central Food Technological Research Institute, Mysore — 570 013, India. Author Rahma is a United Nations University Fellow; present address: Food Science & Technology Dept., Faculty of Agriculture, Univ. of Monoufeia, Shibin-EI-Kom, Egypt.

ABSTRACT

 

Cottonseed flakes were extracted with one of the following solvents: (A) hexane; (B) 1:1 mixture of 85% isopropanol and hexane; and (C)

acetone followed by 1:1 mixture of isopropanol and hexane. Meal B had the lowest free gossypol content of 0.069%. The functional properties and the protein content of all the meals were similar. Ultracentrifugation did not reveal any change in the proportion of the protein fractions. Gel electrophoresis indicated minor differences.

This article is cited by:

I. Vroh Bi, J. P. Baudoin and G. Mergeai. (1998) Cytogenetics of the 'glandless-seed and glanded-plant' trait from Gossypium sturtianum Willis introgressed into upland cotton (Gossypium hirsutum L.). Plant Breeding 117:3, 235–241

Abstract Abstract and References Full Article PDF

Journal of Food Science

Volume 48 Issue 3 Page 988-989, May 1983

To cite this article: HAYTHAM JADDOU, M. AL-HAKIM, L.Z. AL-ADAMY, M.T. MHAISEN (1983) Effect of Gamma-Radiation on Gossypol in Cottonseed Meal Journal of Food Science 48 (3), 988–989. doi:10.1111/j.1365-2621.1983.tb14948.x

Prev Article Next Article

Welcome to Blackwell Synergy - the source of highly cited peer-reviewed society journals from Blackwell Publishing

You are attempting to access the PDF of this article. To access this content you, or your library, will need to have an online subscription to the journal. Alternatively you can purchase immediate access to the article using a credit card.

If you already have an online subscription please login at the top of this page.

To purchase an online subscription to this journal please visit the journal homepage and click on 'Subscribe'.

To purchase immediate access to this article for 30 days through our secure web site using a credit card, please click the 'Full Text Article' or 'PDF' button below, and follow the instructions.

Abstract

Effect of Gamma-Radiation on Gossypol in Cottonseed Meal

HAYTHAM JADDOU11 The authors are affiliated with the Nuclear Research Center, Agriculture & Biology Dept., P.O. Box 765, Baghdad, Iraq.,

M. AL-HAKIM11 The authors are affiliated with the Nuclear Research Center, Agriculture & Biology Dept., P.O. Box 765, Baghdad, Iraq.,

L.Z. AL-ADAMY11 The authors are affiliated with the Nuclear Research Center, Agriculture & Biology Dept., P.O. Box 765, Baghdad, Iraq., and

M.T. MHAISEN11 The authors are affiliated with the Nuclear Research Center, Agriculture & Biology Dept., P.O. Box 765, Baghdad, Iraq.

1The authors are affiliated with the Nuclear Research Center, Agriculture & Biology Dept., P.O. Box 765, Baghdad, Iraq.

The authors are indebted to Dr. A. Pans, of the USDA-ARS Southern Regional Research Center, for the donation of a standard sample of pure gossypol.

ABSTRACT

 The effect of gamma–radiation, in the range 5–30 KGy on free, total and pure gossypol was investigated in an attempt to reduce or eliminate gossypol from cottonseed meal using different solvent systems. Maximum reduction in gossypol concentration was attained at a dose of 25 KGy of gamma-radiation with chloroform as a solvent, a spectrometric method was used for analysis. The reductions attained for

pure, free and total gossypol were found to be 96%, 60% and 80%, respectively.

Journal of Food Science

Volume 46 Issue 6 Page 1726-1733, November 1981

To cite this article: JOHN P. CHERRY, MARIE S. GRAY (1981) Methylene Chloride Extraction of Gossypol from Cottonseed Products Journal of Food Science 46 (6), 1726–1733. doi:10.1111/j.1365-2621.1981.tb04473.x

Prev Article Next Article

Welcome to Blackwell Synergy - the source of highly cited peer-reviewed society journals from Blackwell Publishing

You are attempting to access the PDF of this article. To access this content you, or your library, will need to have an online subscription to the journal. Alternatively you can purchase immediate access to the article using a credit card.

If you already have an online subscription please login at the top of this page.

To purchase an online subscription to this journal please visit the journal homepage and click on 'Subscribe'.

To purchase immediate access to this article for 30 days through our secure web site using a credit card, please click the 'Full Text Article' or 'PDF' button below, and follow the instructions.

Abstract

Methylene Chloride Extraction of Gossypol from Cottonseed Products

JOHN P. CHERRY11 Authors Cherry and Gray (retired) are affiliated with the Southern Regional Research Center, USDA-SEA-AR, P.O. Box 19687, New Orleans, LA 70179. and

MARIE S. GRAY11 Authors Cherry and Gray (retired) are affiliated with the Southern Regional Research Center, USDA-SEA-AR, P.O. Box 19687, New Orleans, LA 70179.

1Authors Cherry and Gray (retired) are affiliated with the Southern Regional Research Center, USDA-SEA-AR, P.O. Box 19687, New Orleans, LA 70179.

Presented at the 39th Annual Meeting of the Institute of Food Technologists, St. Louis, MO, June 10–13, 1979.

The authors express their appreciation to C. James for the quantitative gel electrophoretic analyses of proteins, and to J.H. Carra and J.J. Herbert for the photomicrograph of the gossypol glands.

Names of companies or commercial products are given solely for the purpose of providing specific information; their mention does not imply recommendation or endorsement by the U.S. Department of Agriculture over others not mentioned.

ABSTRACT

 Methylene chloride was used to reduce the amount of free and total (free plus bound) gossypol in hexane-defatted meal and the liquidcyclone-processed (LCP) underflow fraction of glanded cottonseeds from 2.6% and 3.4% to 0.013% and 0.15%, respectively (the accepted level of free gossypol in cottonseed products for food is 0.045%). The cottonseed meals were pretreated one of three ways to rupture the gossypol glands: (a) equilibrated with additional water; (b) suspended in various water-propylene glycol mixtures; or (c) mixed with an acetic acid-water-propylene glycol solution. The gossypol was then readily extracted from the meals with methylene chloride. Low levels of water and acetic acid in propylene glycol aided methylene

chloride in the removal of free and total gossypol and did not greatly alter the proximate composition, solubility, and gel electrophoretic properties of proteins; amino acid content; and chemical scores of the treated meals. Success with this process should improve the potential of LCP-cottonseed by-product (underflow) as feed or food.

This article is cited by:

E. H. RAHMA and M. S. NARASINGA RAO. (1984) Gossypol Removal and Functional Properties of Protein Produced by Extraction of Glanded Cottonseed with Different Solvents. Journal of Food Science 49:4, 1057–1060

Abstract Abstract and References Full Article PDF

Journal of Food Science

Volume 42 Issue 5 Page 1218-1219, September 1977

To cite this article: M. CANELLA, G. SODINI (1977) EXTRACTION OF GOSSYPOL AND OLIGOSACCHARIDES FROM OILSEED MEALS Journal of Food Science 42 (5), 1218–1219. doi:10.1111/j.1365-2621.1977.tb14463.x

Prev Article Next Article

Welcome to Blackwell Synergy - the source of highly cited peer-reviewed society journals from Blackwell Publishing

You are attempting to access the PDF of this article. To access this content you, or your library, will need to have an online subscription to the journal. Alternatively you can purchase immediate access to the article using a credit card.

If you already have an online subscription please login at the top of this page.

To purchase an online subscription to this journal please visit the journal homepage and click on 'Subscribe'.

To purchase immediate access to this article for 30 days through our secure web site using a credit card, please click the 'Full Text Article' or 'PDF' button below, and follow the instructions.

Abstract

EXTRACTION OF GOSSYPOL AND OLIGOSACCHARIDES FROM OILSEED MEALS

M. CANELLA11 Laboratori Ricarche di Base, Snamprogetti S.p.A. Monterotondo, Rome, Italy and

G. SODINI11 Laboratori Ricarche di Base, Snamprogetti S.p.A. Monterotondo, Rome, Italy

1Laboratori Ricarche di Base, Snamprogetti S.p.A. Monterotondo, Rome, Italy

ABSTRACT

 

Removal of gossypol from cottonseed meal and fermentable sugars from soybean meal by butanol-HCl solution was tested. Acidic butanol treatment yields low gossypol cottonseed protein concentrates and low oligosaccharides soy protein concentrates, respectively. This procedure does not appreciably alter proteins, as it is shown by the comparison of electrophoretic patterns of albumins and globulins extracted from meal and corresponding protein concentrates.

This article is cited by:

E. H. RAHMA and M. S. NARASINGA RAO. (1984) Gossypol Removal and Functional Properties of Protein Produced by

Extraction of Glanded Cottonseed with Different Solvents. Journal of Food Science 49:4, 1057–1060

Abstract Abstract and References Full Article PDF

Journal of Food Lipids

Volume 9 Issue 2 Page 161-173, June 2002

To cite this article: F. ZHANG, K. C. RHEE, S. S. KOSEOGLU (2002) ISOPROPYL ALCOHOL EXTRACTION OF COTTONSEED COLLETS: CRUDE OIL COMPOSITION Journal of Food Lipids 9 (2), 161–173. doi:10.1111/j.1745-4522.2002.tb00216.x

Prev Article Abstract

ISOPROPYL ALCOHOL EXTRACTION OF COTTONSEED COLLETS: CRUDE OIL COMPOSITION

F. ZHANG11 Food Protein Research & Development Center Texas A&M University College Station, Texas 77843–2746,

K. C. RHEE11 Food Protein Research & Development Center Texas A&M University College Station, Texas 77843–2746,

S. S. KOSEOGLU11 Food Protein Research & Development Center Texas A&M University College Station, Texas 77843–274611 Corresponding author: TEL: (979) 845– 2749; FAX: (979) 845–2744; E-mail: s-koseoglu@tamu.edu

1Food Protein Research & Development Center Texas A&M University College Station, Texas 77843–2746

1Corresponding author: TEL: (979) 845–2749; FAX: (979) 845–2744; E-mail: s-koseoglu@tamu.edu

ABSTRACT

Isopropyl alcohol (IPA) is an attractive alternative solvent to hexane for use in vegetable oil extraction. The relative efficiencies of IPA and hexane extractions using both cottonseed collets and flakes were evaluated in terms of product composition. The aqueous IPA extracted crude cottonseed oils from expander pretreated collets were analyzed for their nonacylglycerol compositions. The IPA extraction (88, 93, 95 and 97% IPA) resulted in more free fatty acids in the crude oils than did hexane extraction, and the level of the free fatty acids increased as the IPA concentration increased. The phosphorus content was higher in the IPA-extracted oils compared to those of their hexane-extracted counterparts. The HPLC analysis showed that the IPA extractions increased concentrations of phosphatidylcholine (PC), phosphatidylethanolamine (PE), and phosphatidylinositol (PI) in the crude cottonseed oils. More sugar and less gossypol were found in IPA-extracted oils and the level of sugar decreased as the IPA concentration increased. The oil extracted with 95% IPA from the expander-produced collets were lower in free fatty acid, sugar, and gossypol than those obtained from the flakes. The amount of phosphorus in the oil extracted from the collets was approximately 45% higher than that from the flakes. The IPA extraction, in combination with expander pretreatment,

produced cottonseed meals with free gossypol of 366 ppm, making them suitable for feeding nonruminant animals.

Users who read this article also read:

PROPERTIES OF CARICA PAPAYA L. (PAPAYA) SEED OIL FOLLOWING EXTRACTIONS USING SOLVENT AND AQUEOUS ENZYMATIC METHODS T. PUANGSRI, S.M. ABDULKARIM and H.M. GHAZALIPreparation of low-gossypol cottonseed flourSayed M. Damaty, Bertram J. F. HudsonDepartment of Food Science, University of Reading, Reading, EnglandABSTRACTA new laboratory process has been developed for the production of fat-free cottonseed flour with a very low content of both free and bound gossypol. The process depends on the successive extraction of flaked cottonseed meats with (1) hexane and (2) aqueous acetone, followed by anhydrous acetone. The cottonseed flour so derived, with a total gossypol content of about 0.1%and a protein content around 63%is considered appropriate for use in human food.

Received: 8 April 1974; Accepted: 6 August 1974 DIGITAL OBJECT IDENTIFIER (DOI)

10.1002/jsfa.2740260114  About DOIModified Cottonseed May Be Used for FoodBy RANDOLPH E. SCHMIDThe Associated PressMonday, November 20, 2006; 8:38 PM

WASHINGTON -- Cotton, for thousands of years one of the most important crops for clothing and shelter, might also become a source of food. A chemical called gossypol makes cottonseed inedible for humans, though some of it is used in feed for cattle, which are less affected by the toxin. Now, researchers at Texas A&M University have genetically modified cotton to produce seeds with little or no gossypol.

It's a step they say could help provide valuable protein to millions of people. Their findings are reported in Tuesday's issue of Proceedings of the National Academy of Sciences.

Keerti Rathore of the university's Institute for Plant Genomics and Biotechnology, said the modified plants continue to have gossypol in their stems and leaves where it helps resist insects, but the chemical is significantly reduced in the seed.

Worldwide, 44 million tons of cottonseed is produced annually. It is grown in 80 countries and the seeds are 23 percent protein, Rathore said.

They are pressed for oil, and in the United States about half of the remaining meal goes into animal feed, he explained.

But, with the gossypol removed, the meal can be ground into flour and used in cooking, he said.

Rathore said he hasn't tasted the cottonseed meal, but added that

These undated black-and-white photos provided by the Proceedings of the National Academy of Sciences (PNAS) show normal, top and engineered toxin-free, bottom, cottonseeds. Cotton, for thousands of years one of the most important crops for clothing and shelter, might also become a source of food. A chemical called gossypol makes cottonseed inedible for humans, though some of it is used in feed for cattle, which are less affected by the toxin. (AP Photo/PNAS) (AP)

David Woods, a delegate from West Virginia's Berkeley County, shares his views on Mitt Romney during the state's Republican convention. Romney finished second to Mike Huckabee, with John McCain registering just 1 percent. ( Kiichiro Sato -- AP )

SEE FULL

researchers who had bred a different gossypol-free cottonseed had, and reported that tasted good.

Unfortunately, he said, that earlier version removed gossypol from all parts of the plant, which was then attacked by a variety of insects.

Jodi Scheffler, a research geneticist at the Agriculture Department's Agricultural Research Service center in Stoneville, Miss., said the development has potential.

"It definitely gives us new hope," said Scheffler, who was not part of Rathore's research team.

"This is an age-old problem," she explained, the protein contained in cottonseed is good, but cannot be used by people or most animals because it contains this toxin.

The potential problems that have to be worked out, she said, are determining whether the genetic change is stable through generations, and overcoming regulatory and public acceptance problems that can face any genetically modified foods.

One of the reasons it is important is for regions such as West Africa, where many small farmers grow cotton as a cash crop and would like to be able to use the seed to feed themselves and their livestock, she added.

Rathore's research was funded by the Texas Cotton Biotechnology Initiative, Cotton Inc., and the Texas Agricultural Experiment Station.

___

On the Net:

Proceedings of the National Academy of Sciences: http://www.pnas.org

Institute for Plant Genomics and Biotechnology: http://ipgb.tamu.edu

New solvent for cottonseed oil processing.

From: Agricultural Research  |  Date: 8/1/1996  |  Author: Lee, Jill

Print Digg del.icio.us

Petroleum-based solvents that are meant to extract more oil from cottonseeds were initially used during World War I to account for the shortage in oil for food, soaps and explosives. However, a more efficient way of getting oil from seeds was discovered by switching from the oil removing solvent hexane to isohexane. The use of isohexane as an alternative solvent proves to be cleaner, safer and more cost-effective than using hexane. Cottonseed, a billion-dollar industry in the US alone, is mainly used for frying snack foods.

Consider cottonseed oil. It fries the humble potato chip, an American picnic classic. Summer sunbathers glisten with tanning oil made from it.

Cottonseeed was the first major vegetable oil used in the United States. In the 19th century, hydraulic presses were used to remove the oil. Later, continuous screw-type presses offered more efficiency. The shortage of oil for soaps, food, and explosives during World War I prompted the use of petroleum-based solvents to get more oil from the seeds.

Now a scientist with the Agricultural Research Service may have found a more efficient way to meet industry's needs. The key: switching from hexane, the current oil removing solvent, to isohexane, which has several benefits.

"We found that substituting isohexane for hexane in production required little or no change in the cottonseed crushing operation," says chemical engineer Peter J. Wan. "We tested isohexane in plants operating at full capacity and saw both savings in energy and more product produced per hour."

Scientists at ARS began to study alternative solvents during the energy crisis of the 1970's.

At first, their goal was to find more effective solvents, such as acetone, to remove oil and undesirable pigments. Later, renewable solvents that didn't rely on petroleum sources became the focus. But the ideal candidate - ethanol - proved too costly.

During the 1980's and 1990's the focus switched to achieving cleaner, safer, and cost-effective production, so the search for alternative solvents continued.

A research team led by Wan decided to give isohexane a try. The National Cottonseed Products Association also supported him, and some of its members offered their mills to test the new solvent.

"Our experience with isohexane was positive. We saw good extraction and some energy savings," says Billy Clark, president of Yazoo Valley Mill in Greenwood, Mississippi.

"We even reran the test to confirm results. We had no trouble getting isohexane from the supplier for that second test."

"Cottonseed processors have always been industry leaders," says David Kinard, director of research and education for the century-old National Cottonseed Products Association. "Alternative production methods that increase efficiency are appreciated by everyone."

The cottonseed industry represents a billion-dollar U.S. market, says Wan. Each year, 1.4 billion pounds of cottonseed oil are consumed, and their main use is in snack-making.

"Cottonseed oil is considered the 'gold standard' for frying potato chips," says Scott Sanford, who is with the USDA's Economic Research Service. "It's also replacing animal fat in some fast-food restaurants."

"Provided isohexane is economically priced, any oilseed processor could benefit from using it," says Wan. "For example, they'd save energy, because it takes less steam to recover isohexane from the meal and oil during processing."

Peter Wan is in the USDA-ARS Commodity Utilization Research Unit, Southern Regional Research Center, 1100 Robert E. Lee Blvd., New Orleans, LA 70124; phone (504) 286-4450, fax (504) 286-4419, e-mail pwan@nola.srrc.usda.gov

COPYRIGHT 1996 U.S. Government Printing Office This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan. All inquiries regarding rights should be directed to the Gale Group.For permission to reuse this article, contact Copyright Clearance Center.

Print Digg del.icio.us

Gossypol

The use of glanded cottonseed meal is limited in fish diets due to its gossypol content. Gossypol is found in the pigment glands of cotton and may account for as much as 2.4 percent of seed weight in certain varieties (Berardi and Goldblatt, 1980). Free gossypol is tolerated at varying amounts by different fish species, but excessive concentrations can depress growth and cause damage to various organ tissues. Gossypol has also been identified as a carcinogen with aflatoxin B in rainbow trout (Sinnhuber et al., 1968a).

Roehm et al. (1967) reported adverse effects of free gossypol on the growth of rainbow trout fed concentrations of 1,000 mg/kg of diet or higher, but not at 250 mg/kg of diet. Herman (1970) found that although growth depression did not occur at concentrations lower than 290 mg/kg of diet, histopathological changes were noted at 95 mg/kg of diet and included thickening of the glomerular basement membrane of the kidney and necrosis and ceroid deposition in the liver. Wood and Yasutake (1956) noted similar histopathology in rainbow trout. These

results indicate that the maximum concentration of free gossypol in the diets of salmonids should be restricted to 100 mg/kg of diet or less.

Growth inhibition was observed in fingerling channel catfish fed more than 900 mg of free gossypol/kg of diet (Dorsa et al., 1982), but a portion of the depression was possibly due to a dietary lysine deficiency resulting from the irreversible binding of lysine and gossypol (Wilson et al., 1981; Dorsa et al., 1982). In commercial catfish diets in the United States, 10 to 20 percent cottonseed meal is commonly used. Robinson (1991) reported that the solvent extracted cottonseed meal used in catfish diets, which typically contains 400 to 800 mg of free gossypol/kg, would not provide toxic concentrations of free gossypol when mixed into catfish diets; however, the concentration of available lysine in the diet should be scrutinized when cottonseed meal replaces soybean meal. Blue tilapia have been shown to tolerate free gossypol concentrations as high as 1,800 mg/kg of diet with no apparent growth depression (Robinson et al., 1984).

Title: Release of gossypol from cottonseed meal in fermentation medium.

POPLINE Document Number: 003195

Author(s):

Khandeparkar VG

Source citation:

Indian Journal of Experimental Biology, 1981 Jun;19(6):574-6.

Abstract:

Cottonseed meal is a source of rich protein used traditionally in ruminant feeds and even for human nutrition in certain areas of the world. Is is known, however, that gossypol, a toxic substance, is released from cottonseed meal during processing. Toxicity is attributed to free gossypol. Laboratory experimentation was conducted to determined how gossypol is released during fermentation. Cottonseed meal was added to a growth medium of Bacillus subtilis-159 and assayed after 48 hours for the presence of amylase. Cottonseed meal from India and the U.S. were used in the research. Gossypol was released in free form through hydrolyzing of the meal protein by the protease of B. Subtilis. The concentration of gossypol in the assay increased progressively over the incubation time. This released gossypol was inhibitory to the organisms.

Keywords:

Clinical ResearchPlants, MedicinalLaboratory ProceduresIngredients and ChemicalsResearch MethodologyMedicineHealth ServicesDelivery of Health CareHealthLaboratory Examinations and DiagnosesExaminations and DiagnosesIndex page

Antioxidative effects of cottonseed meals as evaluated in cooked meat

K. S. Rhee , , a, Y. A. Ziprina and M. C. Calhounb a Meat Science Section, Department of Animal Science, Texas A&M University, College Station, TX 77843-2471, USAb Agricultural Research and Extension Center, Texas Agricultural Experiment Station, San Angelo, TX 76901, USA Received 6 June 2000; revised 13 October 2000; accepted 13 October 2000 Available online 22 March 2001.

Abstract

Cottonseed meal samples were collected from nine cottonseed oil mills in the USA. The meal samples contained 230–1,820 ppm free gossypol and 8,300–16,480 ppm total gossypol. Finely ground meals were incorporated into ground beef with 15% fat or ground lean meats (beef semimembranosus muscle and goat lean composite), at 0–3% of the final meat mixture weight. The meat mixtures were cooked to an internal temperature of 77°C, aerobically refrigerated for 3 days, and analyzed for lipid oxidation using a distillation 2-thiobarbituric acid-reactive substances (TBARS) assay method. All the cottonseed meals were highly

effective antioxidants in cooked meats, decreasing day-3 TBARS values by 77–91% with 3% addition. Estimated gossypol levels in the meat samples with 3% cottonseed meal were 7–55 ppm free gossypol (vs. the 450 ppm maximum limit set by the United States Food and Drug Administration for human food products) and 249–494 ppm total gossypol (vs. the 12,000 ppm maximum limit by the UN Food and Agriculture and World Health Organizations for food products). There was no significant correlation between the antioxidative efficacy of the meals and free or total gossypol levels.

Author Keywords: Antioxidant; Cottonseed meal; Cooked meat

Supercritical carbon dioxide extraction of cottonseed oil

Paramita Bhattacharjeea, , , Rekha S. Singhala and Sudha R. Tiwarib aFood and Fermentation Technology Department, Institute of Chemical Technology, University of Mumbai, Matunga 400 019, Mumbai, IndiabCentral Institute for Research in Cotton, Adenwala Road, Matunga, Mumbai 400 019, India Received 11 October 2005;  accepted 6 March 2006.  Available online 28 March 2006.

Abstract

Supercritical fluid extraction (SFE) using carbon dioxide is a popular technique for oil extraction due to its high extraction efficiency, short extracting time, lower refining requirement and absence of chemical residues or contamination in the extracted oils. In this work, an attempt has been made to extract oil from a local variety of cottonseed using this technique. The effects of the extraction parameters of pressure, temperature and time of extraction of oil were optimized by using statistical techniques such as central composite rotate design (CCRD) and response surface methodology (RSM), with a view to maximize the oil yield with minimum gossypol extraction. From this study, it could be concluded that the yield of cottonseed oil can be improved at pressure higher than 550 bar, in the temperature zone of 70–80 °C and extracting time of 2–3 h.

Quick method for estimating free gossypol in cottonseed, meats, collets, and extracted meals Journal Journal of the American Oil Chemists'

Society

Publisher Springer Berlin / Heidelberg

ISSN 0003-021X (Print) 1558-9331 (Online)

Issue Volume 73, Number 2 / February, 1996

DOI 10.1007/BF02523895

Pages 199-202

Subject Collection Chemistry and Materials Science

SpringerLink Date

Thursday, November 09, 2006

Add to marked items Add to shopping cart Add to saved items Permissions & Reprints Recommend this article

&lta target="_blank" href="http://adfarm.mediaplex.com/ad/ck/49692?mpt=200802061125167848154"> &ltimg src="http://adfarm.mediaplex.com/ad/bn/49692?mpt=200802061125167848154" alt="Advertisment"> </a>

R. J. Hron Sr.1  , M. S. Kuk1 and P. J. Wan1

(1)  SRRC, ARS, USDA, 70179 New Orleans, Louisiana(2) Southern Regional Research Center, P. O. Box 19687,

70179 New Orleans, LAReceived: 11 August 1995  Accepted: 4 September 1995   Abstract  A method for estimating free gossypol (FG) has been developed that decreases sample-determination time from over 2 h to about 25 min per sample. With auto pipetters and bottle-to dispensers, six sample determinations can be completed in approximately 50 min. The method consisted of adding water and acetone separately to a fixed sample weight, mixing, filtering, diluting with 65% acetone, and reading absorbance on a spectrophotometer. Absorbance was plotted against the official American Oil Chemists’ Society’s FG method for samples that contained FG between 0.02 and 0.9%. Quadratic least squares regression for 31 samples had a correlation coefficient ofr 2=0.986 and a standard error of estimated FG of 0.032%.

Key Words  Analysis - cottonseed - environment - gossypol - plant breeder - polyphenol - spectrophotometer

Presented in part at the AOCS Annual Meeting, Anaheim, California, April 1993.

References secured to subscribers.

Technology Reduces Gossypol In Cotton Seed

ScienceDaily (Jan. 27, 2007) — Genetic technology developed by Agricultural Research Service (ARS) scientists and cooperators suggests that cottonseed could one day become a significant source of low-cost protein for the developing world.

See also: Plants & Animals← Seeds ← Agriculture and Food ← Biotechnology

← Botany ← Genetics ← Life Sciences

Reference← Cotton ← Transgenic plants ← Plant breeding ← Seed predation

The research team, headed by Keerti Rathore at the Institute for Plant Genomics and Biotechnology, Texas A&M University, and ARS chemists Robert D. Stipanovic and Lorraine S. Puckhaber in College Station, Texas, found a way to genetically reduce the amount of the natural toxin known as gossypol in cottonseed.

Stipanovic and Puckhaber are with the ARS Cotton Pathology Research Unit, part of Southern Plains Agricultural Research Center in College Station.

The research team showed that by coupling what's known as RNA interference technology, or RNAi, with a seed-specific gene promoter, it's possible to significantly reduce gossypol levels within cottonseed and not reduce the levels of gossypol and related compounds in the foliage. The presence of these compounds in the foliage helps protect the plant from attack by insects.

Gossypol is a toxic pigment that can be safely ingested only by ruminant animals with complex stomachs, so most of the nutritious meal produced during cottonseed processing is currently sold as cattle feed.

Use of the RNAi technology to develop new cotton lines could lead to plants with low enough gossypol levels in the seed that the 44 million metric tons of cottonseed produced yearly could be used to provide roughly 10 million metric tons of protein. This would help meet the total protein needs of almost a half billion people.

In addition, U.S. consumers craving a new and nutritious snack food could soon be reaching for crunchy "TAMU nuts," which were developed at Texas A&M over 20 years ago. Reduced-gossypol cotton seeds have a nutty flavor and crunch.

The research was published in a recent edition of the Proceedings of the National Academy of Sciences.

ARS is the U.S. Department of Agriculture's chief scientific research agency.

Adapted from materials provided by USDA/Agricultural Research Service.

Need to cite this story in your essay, paper, or report? Use one of the following formats:

APA

MLA USDA/Agricultural Research Service (2007, January 27). Technology Reduces Gossypol In Cotton Seed. ScienceDaily. Retrieved February 7, 2008, from file:///C:/Documents%20and%20Settings/GAURAV%20GOEL/Desktop/SHEETANSHU%20PROJECT/project%20links/Technology%20Reduces%20Gossypol%20In%20Cotton%20Seed.htm

Reducing a toxic compound normally in cottonseed could lead to production of 10 million metric tons of food-grade protein from cotton plants every year. (Photo by David Nance)Ads by Google

Advertise here

Water FuelDiscover Technology That Uses Water To Run A Car.www.Fuel-Rebel.comBiodiesel PlantsBiodiesel Equipment- BioForce9000 Biodiesel Affordable Systemswww.CavitationTechnologies.com

Thilot Seeding MachineA reliable and durable hand seeding machinewww.hz423.comFashion of cotton bagsThe new trends of cotton bags กระเป๋�าผ้าแบบใหม่�www.khundaeng.comMARIBO - Sugar beet seedSugar beet seed of superb quality from Danisco Seed.www.maribo.com

Related Stories

Got Cotton? Texas Researchers' Discovery Could Yield Protein To Feed Millions (Nov. 20, 2006) — Researchers at the Texas Agricultural Experiment Station used RNAi to reduce the toxic compound gossypol from cottonseed to a level that is considered safe for consumption, but left the compound in ...  > read more

Cotton Roots Coaxed Into Producing Promising Compound (Jul. 28, 2005) — When it comes to cotton, it's usually the plants' soft, downy fibers that are the focus of Agricultural Research Service (ARS) scientists. But right now, what's getting their attention is a powerful ... > read more

Remote Sensing Technique Uses Agricultural Aircraft (Apr. 16, 2005) — The need for higher resolution images in remote sensing projects has led to a new technique using agricultural airplanes in the Mississippi ... > read more

Helping Cotton Thrive In The Heat (Dec. 7, 2004) — Cotton grown in the United States comes from areas prone to periods of extremely high temperatures that can have a negative effect on cotton yield. Agricultural Research Service scientists Michael E. ...  > read more