milk fermented products 2013
TRANSCRIPT
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Critical Reviews in Food Science and Nutrition , 53:482–496 (2013)
Copyright C Taylor and Francis Group, LLC
ISSN: 1040-8398 / 1549-7852 online
DOI: 10.1080/10408398.2010.547398
F e r m e n t e d M i l k s a n d M i l k P r o d u c t s
a s F u n c t i o n a l F o o d s — A R e v i e w
V. K. SHIBY1 and H. N. MISHRA2
1Freeze Drying and Animal Products Technology Discipline, Defence Food Research Laboratory, Siddharthanagar, Mysore,
India 5700112Department of Agricultural and Food Engineering, Post Harvest Technology Centre, Indian institute of Technology,
Kharagpur, India
Fermented foods and beverages possess various nutritional and therapeutic properties. Lactic acid bacteria (LAB) play
a major role in determining the positive health effects of fermented milks and related products. The L. acidophilus and
Bifidobacteria spp are known for their use in probiotic dairy foods. Cultured products sold with any claim of health benefitsshould meet thecriteria of suggested minimum number of more than 106 cfu/g at the time of consumption. Yoghurt is redefined
as a probiotic carrier food. Several food powders like yoghurt powder and curd (dahi) powder are manufactured taking into
consideration the number of organisms surviving in the product after drying. Such foods, beverages and powders are highly
acceptable to consumers because of their flavor and aroma and high nutritive value. Antitumor activity is associated with the
cell wall of starter bacteria and so the activity remains even after drying. Other health benefits of fermented milks include
prevention of gastrointestinal infections, reduction of serum cholesterol levels and antimutagenic activity. The fermented
products are recommended for consumption by lactose intolerant individuals and patients suffering from atherosclerosis. The
formulation of fermented dietetic preparations and special products is an expanding research area. The health benefits, the
technology of production of fermented milks and the kinetics of lactic acid fermentation in dairy products are reviewed here.
Keywords Fermented milks, L. acidophilus, bifidobacteria, probiotics, lactic acid bacteria
INTRODUCTION
Healthiness is one of the most frequently mentioned reasons
behind food choices in EU countries (Lappalainen et al., 1998).
Individuals are considered responsible for their own state of
health. Diseases are seen more and more as consequences of
consumer’s own behavior rather than the result of environment
(Ogden, 1998). Diet may strongly influence an individual’s risk
of obesity; cardiovascular diseases, cancer, and other life style
related diseases. Traditionally, the healthfulness has been as-
sociated with nutritional factors such as fat, fiber, salt, and vi-
tamin contents of food. In addition to traditional healthinessfood may contain single components that may have a positive
impact on our well-being. Products that are claimed to have
special beneficial physiological effects in the body are usually
called functional foods (Bellisle et al., 1998; Roberfroid, 1999;
Hardy, 2000; Kwak and Jukes, 2001). A particular food may be
made more functional by increasing or adding a potential health
Address correspondence to Prof. H. N. Mishra, Department of Agriculturaland Food Engineering, Post Harvest Technology Centre, Indian Institute of Technology, Kharagpur-721302, India. E-mail: [email protected]
promoting entity. Alternatively, concentration of adverse com-
ponents may be reduced or there may be a partial interchange
between toxic and beneficial ingredients. Functional food may
be considered as a therapeutic aid without prescription. The
term nutraceutical was coined by Stephen De Felice, founder of
the Foundation for Innovation in Medicine, in 1989. He defined
a nutraceutical as a food, dietary supplement or medical food
that has a medical or health benefit including the prevention or
treatment of disease. Today the term nutraceutical is often used
interchangeably with functional food. An official definition for
the term functional foods is lacking in USA and Europe. Ac-
cording to EU concerted action “a food can be considered asfunctional if it has been satisfactorily demonstrated to affect
beneficially one or more target functions in the body beyond
adequate nutritional effects in a way that is relevant to either
an improved state of health and well-being and/or a reduction
of risk of disease.” These functional foods may also be used as
conventional foods (Diplock et al., 1999).
Thereare several methods of manufacturing functional foods,
based either on the method used to produce them or on their
purpose. Functional foods may be processed by modification
or they may be fortified with different substances and the
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FERMENTED MILKS AND MILK PRODUCTS AS FUNCTIONAL FOODS—A REVIEW 48
functionality of a product can be targeted to a special disease or
just to improve overall well being (Roberfroid, 1999). Informa-
tion relating health effects and the ways of communicating such
information are the key factors because the health effect cannot
be perceived from the product itself (Urala et al., 2003). Since
1989, the nutraceutical or functional food industry has evolved
into a market worth $20.2 billion in 2002. Functional beveragesreached$ 10.35 billion sales in 2002, up 10.7% andare projected
to reach $15.9 billion by 2010. A variety of functional dairy
foods are conquering the market worldwide. Examples include
probiotic, prebiotic, and symbiotic products, low cholesterol
fresh milk omega-3-milk, low lactose, and lactose free products
and milk products that can control or manage hypertension and
immune functions. The market for functional foods, nutraceu-
ticals, wellness foods, and beverages is fast growing and it is
estimated that the functional food industry could almost dou-
ble by 2007. An increasing sector of the public is quickly aging
and purchasingfunctional food products. Today’s consumers are
more concerned with weight loss and management, heart health,
eye health, cancer, increasing energy and stamina, eye health,
and improved memory. Several categories of functional foods
and beverages have been developed to meet these challenges.
The scope of the present article is to provide an overview
of the kinetics of lactic acid fermentation in dairy products,
the technology and nutritional significance of fermented milks
popular in different countries, and the therapeutic properties of
probiotic organisms involved in their manufacture.
LACTIC ACID FERMENTATION
Fermentation Kinetics
Mathematical analysis of the biokinetics of functional starter
cultures can yield precious information about the relationship
between the food environment and bacterial functionality and
may contribute to optimal strain selection and process design.
This may result in better process control, enhanced food safety
and quality, and reduction of economic losses. Kinetic data are
needed to understand the fermentation process and to develop
continuous fermentation systems. Lactic acid bacteria (LAB)
have long been used in food industry as starter cultures for
the manufacture of fermented meat and dairy products. The
key metabolite produced during such fermentation reactions is
lactic acid, which is a commercially valuable product with ap-
plications in food manufacturing and pharmaceutical industries.
Both chemical and biotechnological methods are available for
lactic acid production, but the lactic acid from fermentative pro-
cesses has increased its market share owing to the preference
of consumers to products of natural origin (Chahal, 1989). The
commercial significance of dairy fermentation industry which
incorporates production of cheeses, fromage frais, sour cream,
etc. is well recognized and ranks second only to the alcoholic
beverages (Daly et al., 1998). The processes for wood utiliza-
tion can be directed toward lactic acid production (Moldes et al.,
1999). The kinetics of milk fermentation by starter cultures
has been studied by several research workers. Response Sur-
face Methodology has been successfully used in modeling o
acidification rate and growth of starter bacteria as a functio
of parameters such as fermentation temperature, fat and soli
content, inoculum size, and cocci/rods ratio on the fermenta
tion process of yoghurt (Torriani et al., 1996). The pH mea
surement method described by Spinnler and Corrieu (1989)
widely used in the determination of acidification kinetics duringel formation. Several research workers have tried to optimiz
the acidification process for manufacture of fermented prod
ucts and developed models to predict the acidification kinetic
Mathematical models have been used to predict the influenc
of fermentation operating temperatures on cell growth rate, ce
concentration, substrate utilization rate and lactic acid produc
tion rate. As for models, a number of them, purely or partiall
empirical, have been described in literature. Product inhibitio
is well-established feature of lactic fermentations.
Boonmee et al. (2003) developed a model for batch an
continuous fermentation of Lactococcus lactis strain NZ133
The growth kinetics of L. lactis is predominantly influenced b
lactose limitation and lactate product inhibition with the growt
of this particular strain showing a relatively high sensitivity t
lactate inhibition. The Leudeking-Piret equations for growt
and lactate production were successfully incorporated into th
model. The Leudeking–Piret model is given as
dx
dt = µx (1
dp
dt = α
dx
dt + βx (2
When this is modified to include the effects of lactose limtation and inhibition, as well as lactate inhibition the model
outlined as in Equatons (3)–(5).
The rate of biomass production
dx
dt =
s
Ksx + s
1 −
P − P ix
P mx − P ix
×
Kix
Kix + s
x (3
The rate of lactate production
dp
dt = α
dx
dt + qp,max
s
Ksp + s
×
1 −
p − P ip
P mp− P ip
Kip
Kip + s
x (4
The rate of lactose utilization
ds
dt = qs,max
s
Kss + s
1 −
p − P is
P ms − P is
×
Kis
Kis + s
x (5
where,
K i is lactate inhibition constant (gl−1),
K s is lactose limitation constant (gl−1),
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484 V. K. SHIBY AND H. N. MISHRA
P is lactate concentration (gl−1),
Pi is threshold lactate concentration (gl−1),
Pm is maximum lactate concentration (gl−1),
q p,max is maximum specific lactate production rate (gg−1h−1),
qs,max is maximum specific lactose utilization (gg−1h−1),
s is lactose concentration (gl−1),
x is biomass concentration (gl−1),
a is growth associated constant in Leudeking–Piret model
(gg−1),
b is nongrowth associated constant in Leudeking–Piret model
(gg−1h−1),
µ is specific growth rate in Leudeking-Piret model (h−1), and
µmax is maximum specific rate (h−1)
Common Organisms and Pathways
The group of LAB plays a central role in fermentation pro-
cesses, and has a long and safe history of application and con-sumption in production of fermented foods and beverages. (Ray,
1992; Wood and Holzaphel, 1995; Wood, 1997; Caplice and
Fitzgerald, 1999) During fermentation of lactose to lactic acid
the acidity of the milk rises and the growth conditions for mi-
croorganisms other than LAB become increasingly unfavorable
(Driessen and Puhan, 1988). Reid et al. (2002) have studied the
LAB in fermented foods in South East Asia. They discussed
the distribution and application of LAB in various products
such as fermented milk, meat, fish, vegetable, or plant prod-
ucts. Significant advances have been made in elucidating the
genetic, biochemical land physiological basis of many of the
key technological traits of these bacteria (Daly et al., 1998).
LAB are constituted of heterogenous group of Gram-positivebacteria with a strictly fermentative metabolism (Temmermman
et al., 2004). One of the most important functional properties
common to all LAB is their ability to convert lactose and a va-
riety of other carbohydrates into the primary end product, lactic
acid, by fermentation. The ability of LAB to transform food
into new products and to exert antagonistic action toward harm-
ful microorganisms make them suitable for both domestic and
industrial productions Servin (2004). The LAB involved in the
production of fermented milks are distributed in several phe-
notypic and genotypic groups. These groups are characterized
by different nutritional requirements, metabolic, cultivational,
and technological properties. Several authors have reported that
LAB present in fermented milks may belong to species of Lac-
tobacillus, Streptococcus, Pediococcus, Leuconostoc, and Lac-
tococcus genera (Aucloir and Mocquot, 1974 ; Cogan, 1985;
Gilliland, 1985; Sandine, 1985; Schleifer et al., 1985). The role
of interaction between yeasts and LAB in African fermented
milks has been reviewed by Narvhus and Gadaja, 2003.
There are two main fermentation pathways in LAB; the ho-
molactate pathway in which lactic acid is the major end product
and heterolactate pathway in which other compounds such as
acetic acid, carbon dioxide, ethanol etc. are produced in addi-
tion to lactic acid (Huggenholtz, 1993;Cocaign-Bous-quet et al.,
1996; de Vos, 1996). The homofermentation and heterofermen-
tation pathways are shown in Fig. 1. Both rods and cocci follow
different pathways of carbohydrate fermentation and achieve
end products, which are at least 90 or 50%, lactate in the case
of homo and hetero fermentative species respectively. Lactose
is transported across the cell membrane either by lactose per-
meate system or by phosphoenol pyruvate dependent phosphotransferase system (Lac PEP-PTS ). Depending on the transport
mechanism involved, unphosphorylated lactose (Lac permease)
is hydrolyzed into glucose and galactose by β-galactosidase
or phosphorylated lactose is hydrolysed by phosphorylated β -
galactosidase into glucose and galactose-6-phosphate. All of
the dairy lactococci and some mesophilic lactobacilli oper-
ate the Lac PEP-PTS system (Fig. 2) while leuconostoc and
some industrially significant thermophilic organisms; S. ther-
mophilus and Lb delbrueckii subsp. bulgaricus possess a perme-
ase system (Fig. 3) Subsequent metabolic pathways include the
glycolytic Embden-Meyerhof-Parnas(EMP), the phosphoketo-
lase pathways for glucose, the tagatose-6-phosphate pathway
for galactose-6-phosphate and the Leloir pathway for galac-
tose (when it is not transported back into the environment).
LAB containing aldolase, that is, Streptococci, Pediococci, and
obligately homofermenative and facultative heterofermentative
Lactobacilli have the homolactic fermentation with lactate as the
exclusive end product. LAB containing phosphoketolase can be
divided into twogroups. Thefirst, that is, Leuconostocs and obli-
gately hetero fermentative lactobacilli, follows “6P—gluconate
pathway” with production of equimolar amounts of CO2, lac-
tate and acetate. The others follow “bifidus pathway” with the
formation of acetate and lactate in a molar ratio of 3:2.
Among the LAB, lactose metabolism in lactococcus is prob-
ably the best understood in terms of its biochemical and ge-netic make-up and also in terms of its regulation. The complete
metabolic pathway is known and several important genes have
been characterized (de Vos and Vaughan, 1994). The genes en-
coding the PEP-PTS system and the tagatose pathway are all
plasmid located in a single operon under the control of the
repressor gene lacR. Another operon has also been identified
in Lactococcus encoding a number of glycolytic enzymes The
fermentative action of specific LAB strains may lead to the re-
moval of toxic or antinutritive factors such as galactose and
lactose from fermented milks to prevent lactose intolerance and
accumulation of galactose (Wouters et al., 2002).
Fermentation Process and Health
Fermented milks constitute important part of our food. In an-
cient days, human beings realized that fermentation occurred,
without, however, knowing their cause. Originally milk fer-
mented spontaneously, and the reuse of fermentation vessels
and tools contributed to a certain repeatability and stability in
the fermentation process. This led to the use of specific microor-
ganisms for the manufacture of more or less refined products.
Different countries or even different parts of the same country
developed their own fermented milks. The best-known product
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FERMENTED MILKS AND MILK PRODUCTS AS FUNCTIONAL FOODS—A REVIEW 48
Glucose
Fru-1,6 P Glc-6PFru-6P
Acetyl-P+ Erythrose-4P6P-Gluconate
Heptose-P Xylulose-5P +CO2
+Pentose-P
Triose-3P
Phosphoketolase
aldolase
Triose-3P + Acetyl- P
PyruvatePyruvatePyruvate
Acetyl-P+ Triose-3P
ADP
ATP
ADP
Lactate LactateAcetate (Ethanol )
Lactate Acetate
GlycolysisBifidus pathway 6P-Gluconate pathway
Phosphoketolase pathways
HOMOFERMENTATION HETEROFERMENTATION
Fru-6P
Figure 1 Main pathways of hexose fermentation in lactic acid bacteria (Kandler, 1983).
is the thermophilic fermented milk, yoghurt, which has enjoyed
increased popularity in the last three decades. The role of living
microorganisms in fermented dairy products has gained consid-
erablyincreased interest forboth theconsumerand theproducer.
Nature has provided a certain degree of beneficial association
for humans through the activity of lactic LAB. These bacte-
ria are widely used in foods and agricultural fermentations. In
addition to their preservation, nutritional and therapeutic im-
portance, these are known for their longevity of human life
(Ram and Bhavadasan, 2002) LAB are natural inhabitants o
gastrointestinal tract. These microorganisms have a number o
traits which make them particularly attractive to be used a
“probiotic”. During fermentation of lactose to lactic acid th
acidity of milk rises and the growth conditions of microorgan
isms other than LAB become increasingly unfavorable. Apa
from the main metabolite lactic acid, fermentation microorgan
isms also produce bacteriostatic compounds. It has been sug
gested that the ingestion of LAB may counteract the effect o
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486 V. K. SHIBY AND H. N. MISHRA
Figure 2 Scheme of lactose and galactose utilizati on by lactobacilli and streptococci (Kandler, 1983).
Escherichia coli outgrowth by a number of possible mechanisms
such as anti- E. coli metabolites, detoxification of enterotoxins,
prevention of toxic amine synthesis, andadhesionto thegut, thus
preventing colonization by pathogenic bacteria. These aspects
are comprehensively reviewed by Gurr (1983). Homofermenta-
tive LAB convert the available energy source (Lactose) almost
completely to lactic acid via pyruvate to produce energy and to
equilibrate the redox balance. The fermentation action of spe-
cific LAB strains may lead to removal of toxic or antinutritive
factors, such as lactose and galactose, from fermented milks to
prevent lactose intolerance and accumulation of galactose.
Culture Containing Milk Products in Prevention of Gastro
Intestinal Infections
The beneficial effects of LAB and cultured milks have been
attributed to their ability to suppress the growth of pathogens
either directly or through the production of antibacterial sub-
stances such as lactic acid, peroxide, and bacteriocins (Kodama,
1952; Kansal, 2001). LAB are credited with imparting a number
of nutritional and therapeutic attributes to fermented milk prod-
ucts such as improved digestion and bio availability of milk
constituents, inhibition to harmful bacteria of gastrointestinal
tract, suppression of cancer, alleviation of lactose intolerance,
and hypocholesterolaemic effect (Mathur et al., 2000).
Supplementation of infant formulas with Bifidobacterium
lactis and S. thermophilus has been reported to be protective
against nosocomical diahhroea in infants (Saavedra et al., 1994).
Pediatric beverage containing B. animalis, L. acidophilus, and
L. reuteri has been reported to be useful in prevention of ro-
tavirus diahhroea. Treatment with Lactobacillus GG promotes
systemic local immune response to rotavirus, which may be of
importance for protective immunity against infections (Kalia
et al., 1992). Probiotics reported to reduce antibiotic induced
diahhroea include B. longum, B. lactis, Lactobacillus GG,
L.acidophiluu La5, and Streptococcusfaecum and yeast Saccha-
romyces boulardii (Borgia et al., 1982; Colombel et al., 1987;
Surawicz et al., 1989; Nord et al., 1997). Several strains of lacto-
bacillus have been reported to inhibit Salmonella typhimurium
(Hitchins et al., 1985). Helicobacter pylori is recognized as
the main cause of anal gastritis. Inhibition of H. pylori NCTC
11637 by L. casei subsp. rhamnosus and several strains of
L. acidophilus and production of antihelicobacter factors by
these LAB have been reported (Kawamura et al., 1981; Lam-
bert and Hull, 1996).
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FERMENTED MILKS AND MILK PRODUCTS AS FUNCTIONAL FOODS—A REVIEW 48
Figure 3 Lactose metabolism by Leuconostocs (Cogan, 1985).
TECHNOLOGY OF FERMENTED MILKS
AND MILK PRODUCTS
The nutritional importance and technology of traditional fer-mented dairy products popular in different parts of the world has
been summarized in Table 1. Besides the traditional products
which are popular in various countries, the development of pro-
biotic products, dairy beverages, dietetic preparations, and dry
cultured products are on progress due to the increasing demand
for such value added products and convenience based ingredi-
ents. The process technology for different categories of such
products is described. The major categories include cultured
milks with mesophilic organisms and thermophilic milks. The
organisms involved in their manufacture, metabolites including
flavor compounds produced and their proposed mechanism in
probiotic dairy products are given in Table 2 Dry cultured milk
products, whey based cultured beverages and several dieteticpreparations also find place in the booming health food market.
Cultured Milk
Cultured milk is a collective name applied to a wide range
of mesophilic fermented milks with a number of characteris-
tics in common. Mesophilic organisms are those with growth
optima between 20C and 30◦C. The starters used for fermenta-
tion consist of homofermentative mesophilic LAB and of aroma
producers (Driessen and Puhan, 1988). Mesophilic lactic cu
tures generally grow in the temperature range of 10–40◦C an
contain group N streptococci and/or leuconostocs (Petterson
1988). The final taste of cultured milk is the result of a mixtur
of compounds present in a certain ratio. For example, the d
acetyl flavor is associated with butter and buttermilk. Culture
milk should be mildly acid and slightly pricking. To meet thesrequirements, the content of lactic acid and carbohydrate has t
be controlled during the manufacture of the product. By coo
ing the milk at the proper time, acidification can be limited
whereas the excess of the carbon dioxide in the product at th
end of fermentation can be removed by stirring or de-aeratio
by vacuum.
Milk for production of cultured milk has to be heat treate
in order to inactivate the native substances which are inhibitor
to the LAB and to improve the structure of the final product b
denaturation of whey proteins. To obtain a coagulam that ca
be stirred easily to a smooth and viscous product, 805 or mor
of the whey proteins should be denatured (Snoeren et al., 1981
Richter, 1997) this can be reached by a heat treatment of 90◦
for 3 min or 85◦C for 30 min (Harland et al., 1955; Hillier an
Lyster, 1979).
Lowering of pasteurization temperature of milk results in de
creasing firmness and retarded acidification. Ultra High Tempe
ature (UHT) sterilized milk and other high temperature treate
milks also result in lower viscosity, age-thickening and a cooke
flavor in cultured milks. Homogenization of milk at 55◦C an
20 MPa is sufficient to get good distribution of fat. Decreas
ing milk solids-not-fat content results in taste difference. Th
product may turn “flat” and “watery” and the defect known a
“astringent” may occur. Increasing MSNF of milk leads to
“full” taste, higher viscosity, and a stable cultured milk withouwheying off during cold storage.
Dry Cultured Milk Products
Extensive research has been carried out on various dry cu
tured products including yoghurt, acidophilus milk, kumis
and kefir, usually combined with additives that will enhanc
the nutritive quality of the final product. Starters for dry cu
tured beverages are streptococcus thermophilus, Lactobacillu
bulgaricus, Lactobacillus acidophilus (LA), “Kefir grains”, an
Bifidobacterium adolescens among others (Caric, 1994). Ver
little scientific work has been published in this field and th
developed processes are covered by patents (Pallansch, 1970
Hall and Hedrick, 1975; Shah et al., 1986; Usacheva et al
1990). In general, the processing procedure for these product
differs somewhat from that for conventional cultured produc
(Krsev, 1989). Milk is heated to 90◦C–95◦C for 20 min prio
to culturing. A total solids content of 30% has been found t
be most favorable. Concentration is accomplished either b
vacuum evaporation or ultra filtration. The advantage of u
ing concentrated milk for culturing is volume reduction, an
certain stimulation is provided to microorganisms in this way
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FERMENTED MILKS AND MILK PRODUCTS AS FUNCTIONAL FOODS—A REVIEW 48
Table 2 Probiotic microorganism, metabolites and proposed mechanism in dairy products
Product Microorganisms involved Metabolitesa,/flavorb compounds/probiotic c property
Acidophilus milk L. acidophilus Maintenance of normal intestinal florac, acidophilina
Acidophilus paste L. acidophilus
Acidophilus buttermilk L. acidophilus -do-
Acidophilus yoghurt L. acidophilus, S.thermophilus, L.
delbrueckii.subsp.bulgaricuss.
Acetaldehydeb
Biogurt L. acidophilus, S. thermophilus
Acidophilus—yeast milk L. acidophilus, lactose fermenting yeasts
Probiotic dahi L. acidophilus, L. lactis, L lactis subsp diacetylactis Diacetylb enhanced digestibility, prevents constipation
Bifidus milk Bifidobacterium bifidum, B. longum Removal of toxic aminesc, strengthening of host immune systems
Bifighurt B. bifidum, S. thermpophilus Reduction of serum cholesterol
Biogarde B. bifidum, L. acidophilus, S. thermophilus
Biokys B. bifidum, L. acidophilus, P. acidilactici
Special Yoghurt B. bifidum, L. acidophilus, S. thermophilus, L.
delbrueckii subsp. bulgaricus
Cultura B. bifidum, L. acidophilus
Cultura drink B. bifidum, L. acidophilus
Progurt S.lactis subsp. diacetylactis, S. lactis subsp.cremoris,
l. acidophilus, and/or B. bifidum
Diacetyla Allieviates lactose maldigestionc
a
Metabolites; b
flavor compounds; c
probiotic property.
However, the desired amount of inoculam varies considerably
from 1–6% according to various authors. Even starter quantities
as high as 10–15% have been reported. Various levels of lactic
acid in concentrated milk prior to spray drying were developed.
Most often acid ranges from 0.6–1.1%. Sometimes treatments
intended to minimize the heat-induced changes and to increase
starter survival during drying are carried out as well. Spray dry-
ing temperatures are lower than those commonly used for milk
drying and range from 145–175◦C (inlet air temperatures). Data
have been reported for drying cultured beverages by freeze-
drying on a laboratory scale. The resulting product is of good
solubility and contains viable microflora after recombination.Kumar and Mishra (2003) developed mango soy fortified yo-
ghurt powder. The nutritional and therapeutic value of yoghurt
was improved by supplementing buffalo milk with soymilk, thus
incorporating in the product phytochemicals. By incorporating
soymilk phenyl alanine, iron, thiamin, and niacin contents of
the product increased.
Whey Based Cultured Dairy Products
Current worldwide popularity of fruit flavored drinkable yo-
ghurt offers an excellent opportunity for incorporation of whey
into the development of cultured fruit flavored products (Singh,
2001). Proper amount of stabilizer coupled with heat processing
of the ingredients and homogenization are important aspects in
the manufacture of fermentable cultured dairy drink (Dorde-
vic et al., 1982). For making drinks from sweet or acid whey,
the standardized method involves adding sugar to filtered whey,
pasteurization at 80◦C for 5 min, homogenization at 70◦C, in-
cubation at 43◦C with 2% Lactobacillus helveticus starter for
15–17 h to the pH 3.8–3.95, repasteurization at 85◦C with 5 min
holding, addition of 4–7% fruit juice concentrate, rehomogeni-
sation, cooling to 50◦C and packing into retail containers. The
drink contained 11.65–13.1% total solids, 11.27–11.65% tota
sugar, 0.66–0.78% protein, 0.2–0.3% fat, and 0.42–0.46% min
erals. Mango-molke mix, a popular whey beverage markete
in Europe contains bifidobacteria culture along with whey an
mango juice. Probiotic attributes of LAB may be incorporate
to develop fermented whey beverages. Such beverages may b
beneficial for the people suffering from gastro-intestinal trac
disorders and it also provides nutritional and therapeutic so
drinks (Singh, 2001). Kumar and Tiwari (2003) showed tha
good quality whey based fermented milk beverage can be mad
from a mixture of cheese whey and milk. The fermented beve
age made by admixing 70% of cheese-whey, 0.3% CMC witthe milk resulting in acceptable whey based fermented mil
beverage.
Thermophilic Fermented Milks
The term thermophilic should be reserved for microorgan
isms whose optimum growth temperature lies between 55 an
75◦C. In dairy industry, it tends to be employed to describ
cultures that are most active between 35 and 40◦C. Accordin
to Bianchi-Salvadori (1981) thermophilic yoghurt starters d
not form part of the natural intestinal flora of man nor do the
implant themselves in the intestines. It has, however, been sug
gested that L. delbrueckii subsp. bulgaricus and S. thermophilu
can establish themselves in the intestine and gradually domi
nate the natural microflora. In vitro, studies have indicated tha
L. delbrueckii subsp. bulgaricus is inhibited by bile salts (Lem
bke, 1963). However, these bacteria are also able to resist a hig
degree of acidity and so it is quite feasible that a proportion o
bacteria ingested will reach the intestine in a viable state (Aco
and Labuza, 1972). Mabbit (1977) supports the hypothesis tha
certain strains of L.delbrueckii subsp. bulgaricus could surviv
and compete in the human intestine. This possibility is of grea
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490 V. K. SHIBY AND H. N. MISHRA
importance since it would ensure the absence of putrefactive
microorganisms and hence protect the intestinal health of the
consumer (Dellaglio, 1984).
Fermented Dairy Beverages
The demand for fermented milk beverages is on the rise due
to their positive health effects and nutritive value. The general
requirements of fermented milk beverages are that they should
be light, low calorie, for example, drinking yoghurt has 30%
less energy than conventional yoghurt, refreshing (not causing
thirst), tasteful of agreeable mouth feel, and smooth in tex-
ture. Milk like soft drinks mainly prepared with yoghurt and
mesophilic starter cultures and nonsoft drinks, for example, Ke-
fir and Kumiss with alcohol production fall in the category of
fermented milk beverages. Acidified milk drinks (AMDs) need
a stabilizer, for example, high methoxy pectin if whey forma-
tion is to be avoided. A stabilizer can act in different ways.
An increased steric repulsion between the casein micelles maybe introduced, thus preventing flocculation. Alternatively, a ki-
netic barrier may be imposed against extensive aggregation.
Casein micelles in milk (pH 6.7) are generally assumed to stay
in the suspended state as the result of steric repulsive interac-
tions between the micelles. On acidification of milk to a pH
value around 4, as is done during the preparation of yoghurt,
the native mechanism of stabilization of casein micelles fails.
This failure is believed to be related to the collapse of the ex-
tended conformation of κ-casein chains (Holt, 1982 and De
Kruif, 1998). At pH 6.7 these chains protrude from the surface
of the casein micelle in order to maximise their entropy. This
same tendency to maximize entropy of κ -casein chains causes
the micelles to have a repulsive mutual interaction because over-lap of κ -casein chains of neighboring micelles would result in a
loss of entropy of the chains. This phenomenon is called steric
stabilization. In order to stabilize an AMD of 8.5% milk solids
(not fat), high methoxy pectin has to be added at concentrations
around 0.3% w/w (Trompa et al., 2004). It was found that up
to 90% of this pectin added as a stabilizer to AMDs is not di-
rectly interacting with the milk gel particles (largely consisting
of casein micelles). This nonadsorbing fraction of pectin, which
is, however, necessary to produce a stable AMD can be taken
out of the stable system without loss of stability. Another way
to decrease the amount of ineffective pectin in the AMD is to
increase the energy input during the homogenization step, that
is, after the addition of pectin. This will increase the adsorption
rate of the pectin, and therefore allows for a smaller overall
pectin concentration.
The steps in the manufacture of fermented dairy beverages
include selection of a milk base with low total solids and low
proteins (Rossi and Clementi, 1983; Dellaglo, 1984), selection
of additives such as fruit juice concentrate, colors, artificial
sweetener, sugar stabilizers, etc. taking into consideration their
interactions with fermented milk components (Rasic and Kur-
mann, 1988), Low temperature (e.g.,
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FERMENTED MILKS AND MILK PRODUCTS AS FUNCTIONAL FOODS—A REVIEW 49
1% lactic acid, but for therapeutic purposes 0.6–0.7% is more
common.
Another variation has been the introduction of a sweet aci-
dophilus milk, one in which the LA culture has been added but
there has been no incubation. It is thought that the culture will
reach the gastro intestinal (GI) tract where its therapeutic ef-
fects will be realized, but the milk has no fermented qualities,thus delivering the benefits without the high acidity and flavor,
considered undesirable by some people.
Sour Cream
Cultured cream usually has a fat content between 12–30%,
depending on the required properties. The starter is similar to
that used for cultured buttermilk. The cream after standardiza-
tion is usually heated to 75–80◦C and is homogenized at >13
MPa to improve the texture. Inoculation and fermentation con-
ditions are also similar to those for cultured buttermilk, but thefermentation is stopped at an acidity of 0.6%.
Others
There are a great many other fermented dairy products, in-
cluding Kefir, Kumiss, beverages based on bulgaricus or bifidus
strains, labneh, and a host of others. Many of these have devel-
oped in regional areas and, depending on the starter organisms
used, have various flavors, textures, and components from the
fermentation process, such as gas or ethanol.
Fermented Dietetic Preparations
Dietetic foods are manufactured to meet particular nutri-
tional needs of people whose normal processes of assimilation
or metabolism are changed, or for whom a particular effect is
obtained by a controlled intake of food or certain nutrients.
They may be formulated for people suffering from physiologi-
cal disorders or for healthy people with additional needs (Ben-
der, 1975). The manufacture of dieteic-fermented milks causes
problems with texture (correction with ropy starter cultures and
hydrocolloids) and with flavor (correction with mild acidifying
and aroma forming cultures, lactose- hydrolysis, skim-milk con-
centrate, fruit concentrates, sweeteners, etc.). Fermented milk
products fortified with some dietary components (fiber, vita-
mins, phospholipids, minerals, other bioactive substances). At
present, the most frequently produced fermented dietetic prod-
ucts are calorie reduced and dietary fiber fortified (separated and
combined ones). A small number of dietetic products have been
developed for adults (obesity, sports activity, etc.) and for el-
derly people. Only a few of the presently manufactured dietetic
preparations are fermented, a factor which certainly become of
more significance in the future. The use of selected intestinal
bacteria starter cultures for the preparation of fermented milk
products will be an expanding product area. Sarkar and Misr
(2001) attempted to incorporate Bifidobacterium bifidum NDR
and propionibacterium freudenreichii subsp. Shermanii MTC
1371 along with Yoghurt- YH-3 to obtain dietetic yoghurt wit
enhanced nutritional and therapeutic characteristics. Dieteic yo
ghurt was obtained from skim milk (0.5% fat, 7.64% SNF
heated to 95◦C for 30 min at 1% level each and incubated a42◦C. The dietetic yoghurt possess desirable technological an
dietetic characteristics including antibacterial activity again
pathogenic test organisms. The viable cell populations obtaine
in the product were within the range required for successfu
implantation in the intestine.
FUNCTIONAL ASPECTS OF FERMENTED
MILK PRODUCTS
Fermented Products as Vehicles for Fortification
Fortification of foods can be an efficient tool to combat m
cronutrient deficiencies. The successful application of food fo
tification technology is based on consideration of compatibilit
of vehicle, fortificant, and process. Modified foods includin
those that have been fortified with nutrients also fall within th
realm of functional foods (ADA reports). According to Ame
ican Dietetic Association (ADA) functional foods includin
whole foods, fortified enriched or enhanced foods have poten
tially beneficial effect on the health when consumed as apar
of varied diet on a regular basis at effective levels. Fermente
dairy products, such as yoghurt and soft cheeses, have bee
used in iron fortification programmes (Lysionek et al., 2002
In the iron fortification of powdered nonfat dry milk, ferrousulfate at a level of 10 ppm was found to be stable for a perio
of 12 months. Ferric ammonium citrate and ferric chloride at
level of 20-ppm iron in the reconstituted product gave accep
able results (Coccodrilli and Shah, 1985). Enrichment has bee
used interchangeably with fortification (FAO/WHO, 1994), bu
elsewhere it has been defined as the restoration of vitamins an
minerals lost during processing (Hoffpauer and Wright, 1994
Probiotic Applications
The claimed beneficial effects from the consumption of fer
mented milks were once a debated issue. Research conducte
since the turn of the century has however, enhanced the under
standing of the therapeutic effects resulting from the consump
tion of these products. The probiotic products are now consid
ered helpful in maintaining good health, restoring body vigo
and in combating intestinal and other disease disorders (Mita
and Garg, 1992). Most scientific papers refer to research usin
L. acidophilus and bifidobacterium species as dietary culture
Nearly all probiotics currently on the market contain Lacto
bacilli, Streptococci, Enterococci, or Bifidobacteria. In contra
to Japan, where freeze-dried microorganisms are consumed b
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492 V. K. SHIBY AND H. N. MISHRA
a substantial part of the human population, in Europe, probi-
otic action toward humans is only claimed for certain fermented
dairy products (e.g., yoghurts). Those species that have been
extensively studied so far, with several experimental inocula-
tion of milk for yoghurt manufacture (Prevost & Divies, 1988).
Additional benefits of microencapsulation of cells include: pro-
tection of cells inside the beads from bacteriophages (Steen-son et al., 1987); increased survival during freeze drying and
freezing (Kearney et al., 1990; Sheu and Marshall, 1993; Sung,
1997) The trials on man were mainly carried out with the two
yoghurt bacteria Streptococcus thermophilus and Lactobacillus
bulgaricus. L. casei, Bifidobacteria, and L. acidophilus has also
received important scientific interest, however, only a few hu-
man studies have been reported. From the technological point
of view a good probiotic should be stable and viable for long
periods under storage, should be able to survive the low pH
levels of the stomach, be able to colonize the epithelium of the
gastrointestinal tract of the host, should not be pathogenic and,
last but not least, must be capable of exerting a growth promot-
ing effect or a resistance to infectious diseases (Kalantzopoulos,
1997). Protection of probiotics by microencapsulation in hydro-
colloid beads has been investigated for improving their viability
in food products and the intestinal tract (Rao et al., 1989). This
has been proposed for various dairy fermentations (Champagneet al., 1992a, 1992b, 1994) such as fermentation of whey (Audet
et al., 1989) and continuous Kim and Yoon, 1995); and greater
stability during storage (Kim et al., 1988; Reuter, 1990; Kebary
et al., 1998). Many health benefits have been attributed to fer-
mented dairy products and probiotic microorganisms (Salminen
et al., 1998).
The therapeutic significance of probiotic organisms is sum-
marized in Table 3. In order to exert positive health effects, it
is generally assumed that the microorganisms need to be vi-
able. Therefore, the International Dairy Federation (1997) has
Table 3 Fermented products and therapeutic significance
Clinical condition/symptoms Health benefit of fermented products Reference
Lactose maldigestion • Viable yoghurt well tolerated by lactose-deficient
subjects, L.acidophilus aids lactose digestion.
Morley, 1979; Gilliland, 1989; Kim and Gilliland, 1983
• Manifested by the presence of breath
hydrogen derived from fermentation
of the lactose in the large intestine,
abdominal pain, meteorism, bloating,
flatulence and diarrhea.
• The presence of bacterial b-galactosidase in the
viable yoghurt culture.
Hepatic encephalopathy
• A neurological disorder where
Detoxification of ammonia produced
in the intestine is impaired in patients
with liver failure.
• Alteration of the intestinal microflora Macbeth et al., 1965; Kavasnikov and Sodenko, 1967;
Read et al., 1968 Loguerolo et al., 1987• A decrease in faecal urease, a lowering of blood
ammonia and clinical improvement when treated
individually with L. acidophilus, Lactobacillus
GG, and E. faecum. SF68
Side effects of radiotherapy
• Radiotherapy alters the intestinal
microflora, vascular permeability of
the mucosa and intestinal motility.
• Treatment with fermented milk containing NCFB
1748 significantly decrease pelvic radiotherapy
associated diarrhea
Salminen et al., 1998 ; Kansal, 2001
Tumor or defective immune systems • Lactobacilli and their metabolic products modify
both the immune responses and antitumor
activities.
Kansal, 2001
• Enhanced mainly by activating macrophage
functions and increasing the activity of natural
killer cells and T-cells, maintenance of normal
intestinal flora
Varnam and Sutherland (1994). Anand et al., 1985
• Help removal of dietary procarcinogens. Benno et al., 1984
High serum cholesterol levels • L.acidophilus strains and some bifidobacteria
species lower cholesterol
Mann and Spoerry, 1974; Kawamura et al., 1981;
Gilliland et al., 1985; Gilliland, 1989; Walker and
Gilliland, 1993; Hosona and Tono-oka, 1995; Gopalet al., 1996; Marshall, 1996; Usman and Hosono,
2000; Gupta and Prabhu (2004)
Renal mal function • Effect of fermented milk product on cholesterol
metabolizing enzymes systems in liver
• Promotion of excretion of cholesterol through
faeces,
• Inhibition of cholesterol adsorption by the binding
of cholesterol to cells of LAB.
• The promotion of excretion by binding of bile salts
to lactic acid bacterial cells.
• Bifidobacterium spp.; Lactobacillus acidophilus
• Reduce level of toxic amines.
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FERMENTED MILKS AND MILK PRODUCTS AS FUNCTIONAL FOODS—A REVIEW 49
defined fermented milk as a milk product fermented by the ac-
tion of specific microorganisms and resulting in reduction of
pH and coagulation. These specific microorganisms shall be
viable, active, and abundant (at least 107 cfu / g) in the prod-
uct to the date of minimum durability. Probiotics are defined as
live microbial food supplements which beneficially influence the
host by improving its intestinal microbial balance (Fuller, 1989;Ziemer and Gibson, 1998). Both definitions emphasize the vi-
ability of microorganisms. Whether viable microorganisms are
necessary for specific health benefits remains unclear. Health
benefits discussed are: alleviation of lactose maldigestion, ef-
fects on diarrhoea, immune-stimulation, antitumor activity, an-
timutagenic activity, reduction of serum cholesterol, and effects
on candidiasis. Many of the studies discussed here were not
conducted for the purpose of determining the efficacy of non-
viable bacteria or fermented milks, but killed microorganisms
have often been used as placebo. The results from these studies
give an indication of the activity of viable versus nonviable mi-
croorganisms and assist in defining the need for probiotics to be
viable.
Fermented Milk Products With Selected Strains
of Intestinal Bacteria
Fermented products containing pure strains of LA, bifidofac-
teria, or either of these in combination with other LAB fall in
the group of probiotic foods and beverages. Important progress
has been made in the study of gut bacteria in relation to their
distribution, metabolic activities, and significance in health and
disease. The potential beneficial roles of indigenous lactobacilliand bifidobacteria are described in many publications (Sandine
et al., 1972; Poupard et al., 1973; Speck, 1976; Shahani and
Chandan, 1979; Rasic and Kurmann, 1983; Goldin and Gor-
bach, 1984) The technology of some of these products has been
given by Rasic and Kurmann (1988). A list of such products and
the organisms associated with them is shown in Table 3. The
concept of yoghurt as aprobiotic carrier food has been reviewed
by Lourens-Hattingh et al., 2001.
Ishibashi and Shimamura (1993) reported that the fermented
milks and LAB beverages association of Japan has developed a
standard which requires a minimum of 107 viable bifidobacteria
cells/ml to be present in fresh dairy products. The criteria de-
veloped by National Yoghurt Association (NYA) of the UnitedStates specifies 108 cfu/g of LAB at the time of manufacture as a
prerequisite to use the NYA “Live and Active Culture” Logo on
the containers of the products (Kailasapathy and Rybka, 1997).
Several publications indicate that fermented milks have antimi-
crobial properties (Jay, 1982), antitumor activities (Reddy et al.,
1983; Shahani et al., 1983) and antileukemic activity (Esser
et al., 1983) The therapeutic significance of fermented prod-
ucts are given in Table 3. The potential therapeutic benefits of
health promoting fermented dairy products are briefly updated
by Itsaranuwat et al. (2003).
Future Research Prospects
The development of more probiotic products by the incor
poration of probiotic organisms into the manufacturing proces
for well-accepted traditional dairy products is to be explore
significantly. The development of convenience based dry cu
tured products containing viable bacteria by various technique
such as microencapsulation and the fortification of such powder
or concentrated products with minerals and vitamins are gain
ing importance. The preparation of suitable blends containin
healthful ingredients such as dietary fiber, natural vitamins an
folic acid also offers new possibilities for this widely expandin
research area. The formulation of various health drinks and d
etetic preparations as value added products based on traditiona
fermented products will definitely bring more opportunities t
the beverage industry. There is a need to intensify research t
distinguish the therapeutic benefits of viable and nonviable or
ganisms in different fermented products apart from the genera
nutrient enhancement achieved.
REFERENCES
Acott, K. M. and Labuza, T. P. (1972). Yoghurt: is it truly Adelle’s vitam
factory? Food Prot. Develop. 6:50–97.
Agerback, M., Gerdes, L. U., and Richelson, B. (1995). H ypocholesterolaem
effect of a new fermented milk product in healthy middle aged men. Eur.
Clin. Nutr. 49:346–352.
Akalin, A. S., Gonc, S., and Duzel, S. (1997). Influence of yoghurt an
acidophilus yoghurt on serum cholesterol levels in mice. J. Dairy Sc
80:2721–2725.
Anand, S. K., Srinivasan, R. A., and Rao, L. K. (1985). Antibacterial activit
with bifidobacterium bifidum. Cult. Dairy. Prod. J. 20
:21–23.Aneja, R. P. (1989). World Survey of Traditional Milk Products. India an
Neighbouring Countries Including the Himalayan Region. FAO Manuscri
Publications Division, Food and Agriculture Organization of the United N
tions, Via delle Terme di Caracalla, 00100 Rome.
Auclair, J. and Mocquot, G. (1974). Cultured milk: Milk products in the futur
J. Rothwell, eds. Society of Dairy Technology, UK, 33–36.
Audet, P., Paquin, C., and Lacroix, C. (1989). Sugar utilization and acid produ
tionby free and entrappedcells of Streptococcus salivarius ssp. thermophilu
Lactobacillus delbrueckii ssp. bulgaricus, and Lactococcus lactis ssp. lact
in whey permeate medium. Appl. Environ. Microbiol. 55:185–189.
Bekele, E. and Kassaye, T. (1987). International Livestock Centre for Afric
Newsletter . 6(4).
Bellisle, F., Blundell, J. E., and Dye, L. (1998). Functional food science an
behaviour and physiological functions. Br. J. Nutr. 80:173–193.
Bender, A. E. (1975). Dictionary of Nutrition and Food Technology. Butte
worths, London, Boston.
Benno, Y., Sawada, K., and Mitsuoka, T. (1984). The intestinal microflo
of infants: composition of faecal flora in breast-fed and bottle fed infant
Microbiol. Immunol. 28:975–986.
Bianchi-Salvadori, B. (1981). Passage des lactobacillus du yoghurt dans
tube digestif. Symposium International sur les Effets Nutritional de la Flo
Digestive, Texte des exposes’, Paris.
Boonmee, M., Leksawasdi, N., Bridge, W., and Rogers, L. P. (2003). Batc
and continuous culture of Lactococcus lactis NZ133; experimental data an
model development. Biochem. Eng. J. 14:127–135.
Borgia, M., Sepe, N., Brancato, V., and Borgia, R. A. (1982). A controlle
clinical study on Streptococcus faecum preparation for the prevention of sid
reactions during long term antibiotic therapy. Curr. Ther. 31:265–271.
-
8/19/2019 Milk Fermented Products 2013
14/16
494 V. K. SHIBY AND H. N. MISHRA
Bulletin of International Dairy Federation. (1988). Fermented Milks Science
and Technology. D. Doc No. 227.
Bulletin of International Dairy Ferderation. (1997). Standard for Fermented
Milks. D. Doc No. 316.
Caplice, E. and Fitzgerald, G. F. (1999). Food fermentations, Role of mi-
croorganisms in food production and preservation. Int. J. Food Microbiol.
50:131–149.
Caric, M. (1994). Dry cultured milks. In: Concentrated and Dried Dairy Prod-ucts, pp. 146–147. Hui, Y. H. (Eds). VCH Publishers, New York.
Chahal, S. P. (1989). Lactic Acid, Ullman’s Encyclopedia of Industrial Chem-
istry. VCH, Verlag, Berlin.
Champagne, C. P., Gaudy, C., Poncelet, D., and Neufeld, R. J. (1992a). Lacto-
coccus lactis release from calcium alginate beads. Appl. Environ. Microbiol.
58(5):1429–1434.
Champagne, C. P., Girard, F., and Rodrigue, N. (1993). Production of concen-
trated suspensions of thermophilic lactic acid bacteria in calcium-alginate
beads. Intl. Dairy J. 3:257–275.
Champagne, C. P., Lacroix, C., and Sodini-Gallot, I. (1994). Immobilized cell
technologies for the dairy industry. Crit. Rev. Biotechnol. 14:109–134.
Champagne, C. P., Morin, N., Couture, R., Gagnon, C., Jelen, P., and Lacroix,
C. (1992b). The potential of immobilized cell technology to produce freeze-
dried, phage-protected cultures of Lactococcus. Appl. Environ. Microbiol.
58:1429–1434.Choi, H. S. and Kosikowski, F. V. (1985). Sweetened plain and flavoured car-
bonated yoghurt beverages. J. Dairy Sci. 68:613–619.
Cocaign -Bous-quet, M., Garrigues, C., Loubiere, P., and Lindley, N. D.
(1996). Physiology of pyruvate metabolism in lactococcus lactis. Antonie
Van Leeuwenhock. 70:253–276.
Coccodrilli, G. a nd Shah, N. (1985). Beverages. In: Iron Fortification of Foods,
pp. 145–154. Clydesdale, F. M. and Wiemer, K. L., Eds., London: Academic
Press.
Cogan, T. M. (1985). The Leuconostocs: Milk Products in Gilliland, S. E. (Ed.).
“Bacterial Starter Cultures for Foods”, pp. 25–40. CRC Press Inc., Boca
Raton, Florida.
Colombel, J. F., Cortot, A., Neut, C., and Romond, C. (1987). Yoghurt with bi-
fidobacterium longum reduces erythromycin induced gastrointestinal effects.
Lancet. 2:43.
Daly, C., Fitzgerald, G. F., O’Connor, L., and Davis, R. (1998). Technological
and health benefits of dairy starter cultures. Indian Dairy J. 8:195–205.
De, S. (1980). Outlines of Dairy Technology: Dahi. Oxford University Press,
New Delhi.
Deeth, H. C. and Tamime, A. Y. (1981). Yoghurt:Nutritive value and therapeutic
aspects. J. Fd. Prod. 44:78–86.
De Kruif, C. G. (1998). Supra-aggregates of casein micelles as a prelude to
coagulation. J. Dairy Sci. 81:3019–3028.
Dellaglio, F. (1984). Thermophilic Lactic Acid Bacteria, Fil. IDF- Bulletin Doc
No. 179, pp. 73.
de Vos, W. M. (1996). Metabolic engineering of sugar catabolism in lactic acid
bacteria. Antonie Van Leeuwenhock. 70:223–242.
de Vos, W. M. and Vaughan, E. E. (1994). Genetics of lactose utilization in
lactic acid bacteria. FEMS Microbiol. Rev. 15:217–237.
Diplock, A. T., Agget,P.J., Ashwell, M.,Bornet,F.,Fern, E. B.,and Roberfroid,
M. B. (1999). Scientific concepts of functional foods in Europe. Consensus
document. Brit. J. Nutr. 81:1–27.Dordevic, J., Niketic, G., Karic, A., Bubanjo, N., and Markoviv, D. (1982). Use
of sweetand sourwheyin theproduction of fermentedbeverages. Mljekarstov.
32:214–218.
Driessen, F. M. and Puhan, Z. (1988). Technology of Mesophilic Fermented
Milk. Bulletin of IDF No. 227, pp. 75–80.
Esser, P., Lund, C., and Clemmersen, J. (1983). Antileukemic effects in
mice from fermentation of Lactobacillus bulgaricus. Milchwissenchaft.
38:257–260.
FAO/WHO. (1994). Codex Alimentarius, Vol. 4, 2nd edn. FAO: Rome.
Flippov, V. A. (1980). Some properties of bacteriocins from lactobacilli belong-
ing to streptobacterium. Antibiotiki. 24:837–840.
Fuller, R. (1989). Probiotics in Man and Animals. J. Appl. Bacteriol.
66:365–378.
Gandhi, D. N. and Nambudiripad, V. K. N. (1981). Antagonistic effect of cell
free culture filtrate and isolation of antibiotic from Lactobacillus acidophilus
culture from dahi (curd). Indian J. Dairy Sci. 34:334–336.
Gilliland, S. E.(1985). Bacterial Starter Cultures for Foods. CRC Press. Inc.,
Boca Raton, Florida.
Gilliland, S. E. (1989).Acidophilus milkproducts. A review of potential benefitsto consumers. J. Dairy. Sci. 72:2483–2494.
Gilliland, S. E., Nelson, C. R., and Maxwell, C. (1985). Assimilation of choles-
terol by lactobacillus acidophilus. Appl. Environ. Microbiol. 49:377–385.
Gilliland, S. E. andSpeck, M. L. (1977). Instability of Lactobacillus acidophilus
in yoghurt. J. Dairy Sci. 60:1394–1398.
Goldin, B. R. and Gorbach, S. L. I. (1984). The effect of milk and lactobacillus
feeding on human intestinal bacterial enzyme activity. Am. J. Clin. Nutr.
39:756–761.
Gopal, A., Shah, N. D., and Roginski, H. (1996). Bile tolerance, taurocholate
deconjugation and cholesterol removal by L.acidophilus and bifidobacterium
spp. Milchwissenchaf. 51:619–623.
Gupta, P. K. and Prabhu, T. R. (2004). Hypocholosterolaemic activity of lacto-
bacillus acidophilus. J. Food Sci. Tech. Mys. 41:695–603.
Gurr, M. (1983). Cultured Dairy Foods in Human Nutrition. IDF Doc No. 159,
pp. 1–28.Hall, W. and Hedrick, T. I. (1975). Drying of Milk and Milk Products. AVI
Publishing Company, West Port, CT.
Hardy, G. (2000). Nutraceuticals and functional foods: introduction and mean-
ing. Nutr . 16:688–697.
Harland, H. A., Coulter, S. T., Townley, V. H., and Jenness, R. (1955). A quan-
titative evaluation of changes occurring during heat treatment of skimmed
milk at temperatures ranging from 170◦ to 300◦ F. J. Dairy Sci. 38:1199–
1207.
Hege, W. U. and Kessler, H. G. (1986). Deposit formation of protein containing
dairy liquids. Milchwissenchaft. 41:356–360.
Hillier, R. M. and Lyster, R. L. J. (1979). Whey protein denaturation in heated
milk and cheese whey. J. Dairy Res. 46:95–102.
Hirata, T. (1992). Cholesterol lowering activity of ropy fermented milk. J. Food
Sci. 57:1327–1329.
Hitchins, A. D., Wells, P., Mcdonough, F. E., and Wong, N. P. (1985). Ame-
lioration of adverse effects of a gastro intestinal challenge with Salmonella
enteriditis on weaning rats by a yogurt diet. Am. J. Clin. Nutr. 41:91–100.
Hoffpauer, D. W. and Wright, S. L. (1994). Enrichment of rice, pp. 287–314.
In: Rice Science and Technology. Marshall, W. E. and Wadsworth, J. I., Eds.,
Marcel Rekker, New York.
Holt, C. (1982). Structure and stability of the bovine casein micelle. In: Ad-
vances in Protein Chemistry, pp. 63–151. Afinsen, C. B., Sall, J. D. E. D.,
Richards, F. K. and Eisenberg, D. S., Eds., Academic Press, New York.
Hosona, A. and Tono-oka, T. (1995). Binding of cholesterol with lactic acid
bacterial cells. Milchwissenchaft. 51:619–623.
Huggenholtz, J. (1993). Citrate metabolism in lactic acid bacteria. FEMS Mi-
crobiol. Rev. 12:165–178.
Ishibashi, N. and Shimamura, S. (1993). Bifidobacteria: Research and develop-
ment in Japan. Food Technol. 47:126, 129, 134.
Itsaranuwat, P., Khawla, S. H. Al-Haddad, and Robinson, R. K. (2003). The
potential therapeutic benefits of consuming ‘health-promoting’ fermenteddairy products: a brief update. Intl. J. of Dairy Technol. 56:203.
Jay, J. M. (1982). Antimicrobial properties of diacetyl. Appl. Envl. Microbiol.
44:525–532.
Kailasapathy,K. andRybka, S. (1997). L. acidophilus and Bifidobacterium spp.-
their therapeutic potential and survival in yoghurt. Aust. J. Dairy Technol.
52:28, 35.
Kalantzopoulos, G. (1997). Fermented products with probiotic quality. Anaer-
obe. 3:185–190.
Kalia, M., Isolauri, E., Soppi, E., Virtanen, E., Laine, S., and Arvilimmi, H.
(1992). Enhancement of circulating antibodysecreting cellresponsein human
diahhroea by a human lactobacillus strain. Ped. Res. 32:141–144.
-
8/19/2019 Milk Fermented Products 2013
15/16
FERMENTED MILKS AND MILK PRODUCTS AS FUNCTIONAL FOODS—A REVIEW 49
Kandler, O. (1983). Carbohydrate metabolism in lactic acid bacteria. Antonie
Van L eeuvenhoek. 49:209–224.
Kang, K. H. and Lee, C. N. (1984). Precipitation of milk proteins in cultured
milk beverage. Korean. J. Appl. Microbiol. Bioengg. 12:73–79.
Kansal, V.K. (2001). Probiotic application of culture a nd ulture containing milk
products. Indian Dairy Man. 53:49–55.
Kavasnikov, E. I. and Sodenko, V. I. (1967). Antibiotic properties of lactobacil-
lus brevis. Dairy Sci. Abstr. 29:3972.Kawamura, T., Ohnuki, K., and Ichida, H. (1981). A clinical study on a Lacto-
bacillus casei preparation (LBG-01) in patients with chronic irregular bowel
movement and abdominal discomfort. Jpn. Pharmacol. Ther. 9:4361–4370.
Kearney, L., Upton, M., and Loughlin, A. (1990). Enhancing the viability of
Lactobacillus plantarum inoculum by immobilizing the cells in calcium-
alginate beads. Appl. Environ. Microbiol. 56:3112–3116.
Kebary,K. M.K., Hussein,S. A.,and Badawi, R.M. (1998). Improving viability
of Bifidobacteria and their effect on frozen ice milk. Egyptian J. Dairy Sci.
26:319–337.
Kerven, C. (1987). The role of milk in a pastoral diet and economy: The case
of South Darfur, Sudan. ILCA Bulletin No. 27, pp. 18–27.
Kilara, A. and Treki, N. (1984). Use of lactobacilli in foods-unique benefits.
Dev. Ind. Mi crobiol. 25:132.
Kim, H. S., Kamara, B. J., Good, I. C., and Enders, G. L. (1988). Method
for the preparation of stabile microencapsulated lactic acid bacteria. J. Ind. Microbiol. 3:253–257.
Kim, H. S. and Gilliland, S. (1983). Lactobacillus acidophilus as a dietary
adjunct for milk to aid lactose digestion in humans. J. Dairy Sci. 66:956–966.
Kim, K. I. a nd Yoon, Y. H. (1995). A study on the preparation of direct vat lactic
acid bacterial starter. Korean J. Dairy Sci. 17:129–134.
Klaenhammer, T. R., Kleeman, E. G., and Barefoot, S. F. (1983). Bacteriocin
of lactobacilluis acidophilus: evidence for plasmid linkage of lactacin activ-
ities. In: Lactic Acid Bacteria in Foods. Symposium, Netherlands Society of
Microbiology.
Kodama, R. (1952). Studies on lactic acid bacteria. II. Lactolin a new antibiotic
produced by lactic acid bacteria. J. Antibiot. 5:72–74.
Koroleva, N. S., Lagoda, I. V., Bannikova, L. A., Kosareva, L. V., Pospelova, V.
V., Rakhimova, N. G., Korolev, D. D., Gudachkova, V. M., and Shkundova,
Yu. v. (1983). Method of producing acidophilus cultures. USSR Patent 1 004
471 A. Dairy Sci. Abstr. 46.
Koroleva, N. S., Pyatnitsyna,I. N., and Lozovetskyaya, V. T.(1984). Selectionof
starters for manufacture of cultured milk beverages. Moloch. Prom. 6:17–20.
Krsev, L. j. (1989). Microbial Starters in Dairy Technology, Udiuzenje ml-
jekarskih radnika. SRH, Zagreb, Croatia, 129 pp. (in croatian)
Kumar, A. and Tiwari, B. D. (2003). Development of whey based fermented
milk beverage. J. Dairying. Foods and H.S. 23:236–239.
Kumar, P. and Mishra, H. N. (2003). Technology for production of mango soy
fortified yoghurt. 5th International Food Convention 5–8 December, 2003,
Association of Food Scientists and Technologists (India), Mysore, India.
Kurmann, J. A. (1988). Starters for fermented milks. Section 5. starters with
selected intestinal bacteria. Bulletin of IDF No. 227, pp. 41–56.
Kwak, N. S. and Jukes, D. J. (2001). Functional foods part 2 the impact on
current regulatory terminology. Food Control. 12:109–117.
Lambert, J. and Rand Hull, R. R. (1996). Upper gastrointestinal tract disease
and probiotics. Asia Pacific. J. Clin. Nutr. 5:31–35.
Lappalainen, R., Kearney, J., and Gibney, M. (1998). A pan European surveyof consumer attitudes to food, nutrition and health: an overview. Food Qual.
Prefer. 9:467–478.
Lembke, A. (1963). L’Influence des laits fermentes’ sur la flora intestinale.
Milchwissenchaft. 18:215–221.
Loguerolo, C., Vechhio, B., and Collorti, M. (1987). Enterococcus lactic acid
bacteria strain SF68 and lactulose in hepatic encephalopathy:a controlled
study. J. Intern. Med. Res. 15:335–343.
Lourens-Hattingh, A. and Bennie, C. Viljoen (2001). Yoghurt as a carrier food.
Int. Dairy J. 11:1–17.
Lysionek, A. E., Zubillaga, M. B., Salguiero, M. J., Pinerio, A., Caro, A. R.,
Weill, R., and Boccio, R. J. (2002). Bioavailability of microencapsulated
Ferrous Sulphate in powdered milk produced from fortified fluid milk:
prophylactic study in rats. Nutr. 18(3):279–281.
Mabbit, L. A. (1977). Research at the national institute for research in dairyin
in relation to the dairy industry. J. Soc. Dairy Technol. 30:220–227.
Macbeth, W. A., Kass, E. H., and McDermott, W. V. (1965). Treatment o
hepatic encephalopathy by alteration of intestinal flora with Lactobacillu
acidophilus. Lancet. 1:399–403.
Maeno, M., Yamamoto, N., and Takano, T. (1996). Identification of an antihypertensive peptide from casein hydrolysate produced by a proteinase fro
lactobacillus helveticus CP790. J. Dairy Sci. 79:316–1321.
Mann, S. V. and Spoerry, Y. (1974). Studies of a surfactant and cholesterolem
in the massai. Am. J. Clin. Nr. 27:464–470.
Marshall, V. M. (1996). Bioyoghurt. How healthy? Dairy Ind. Int. 61:28–29.
Mathur, B. N., Thompkinson, D., and Sabhiki, L. (2000). Milk the nectar fo
living beings. Indian Dairy Man. 52:11–19.
Mikolajcik, E. M. and Hamdan, I. Y. (1975). Lactobacillus acidophilus. I
antimicrobial agents. Cult. Dairy Prod. J. 10:18.
Mital, B. K. and Garg, S. K. (1992). Acidophilus milk products:Manufactu
and therapeutics. Food Rev. Int . 8:347–389.
Moldes, A.B., Alonso, J. L.,and Parajó, J. C. (1999). Cogenerationof cellobio
and glucose from pretreated wood and bioconversion to lactic acid. J. Biosc
Bioeng. 87:787–792.
Morley, R. G. (1979). Potential of liquid yoghurt. Cult. Dairy Product. 14:30–33.
Narvhus, J. A. and Gadaja, T. H. (2003). The role of interaction between yeas
and lactic acidbacteriain African fermentedmilks In 23rdspecialized symp
siumon Yeasts, BudapestHungary,26–29August2003. Int. J. food Microbio
86:51–60.
Nord, C. E., Lidbeck, A., Orrhage, K., and Sjstedt, S. (1997). Oral supplemen
tation with lactic acid bacteria during intake of clindamycin. Clin. Microbio
Infect. 3:124–132.
Ogawa, T., Hirai, R., Nakakuni, H., Sato, Y., Wakisaka, S., Tachibana, M
Tominaga, H., Kurata, M., and Matsubayashi, K. (1974). Clinical experien
withthe use of the highconcentration lactic acid bacteria preparation, LP-20
to tract constipation. Clin. Rep. 6:1085–1092.
Ogden, J. (1998). Health Psychology, A Text Book. Open University Pres
Trowbridge.
Pallansch, M. J. (1970).Dried products.In: Byproducts fromMilk,pp. 124–18
Webb, B. H. and Whittier, E.O., Eds., AVI Publishing Company, Westpor
CT.
Petterson, H. (1988). Mesophilic Starters In: Starters for Fermented Milk
Bulletin of IDF No. 227, pp. 27–34.
Petterson, H. (1988). Starters for Fermented Milks. Bulletin of IDF No. 227
pp. 27–34.
Poupard, J. A., Hussain, J., and Morris, R. F. (1973). Biology of the bifidobac
teria. Bact. Rev. 37:136–165.
Prevost, H. and Divies, C. (1988). Continuous pre-fermentation of milk by en
trapped yoghurt bacteria. I. Development of the process. Milchwissenschaf
43:621–625.
Ram, C. and Bhavadasan, M. K. (2002). Probiotic dairy foods-present statu
and future perspectives. Indian Dairy Man. 54:53–57.
Rao, A. V., Shiwnarain, N. and Maharaj, I. (1989). Survival of microencap
sulated Bifidobacterium pseudolongum in simulated gastric and intestin
juices. Can. Inst. Food Sci. Technol. J. 22:345–349.Rasic, J. I. and Kurmann, J. A. (1988). Technology of Fermented Special Prod
ucts. Bulletin of IDF No. 227, pp. 101–109.
Rasic,J. l. andKurmann, J. A. (1983). Bifidobacteria andtheir role. In: Microb
ological, Nutritional- Physiological, Medical and Technological Aspects an
Bibliography’ Expentia Supplementum Vol. 39. Birkhauser Verlag, Basel.
Ray, B. (1992). The need for biopreservation. In: pp. 1–24. Food Biopreserv
tives of Microbial Origin Boca Raton, Ray, B. and Daeschel, M., Eds., CR
Press, Florida.
Read, A. E.,Mc Carthy, C. F., andHeaton, K. W. 1968. lactobacillis acidophilu
(ENPAC) in treatment of hepatic encephalopathy. Br. Med. J. 1:1267
1269.
-
8/19/2019 Milk Fermented Products 2013
16/16
496 V. K. SHIBY AND H. N. MISHRA
Reddy, G. V., Friend, B. A., Shahani, K. M., and Farmer, R. E. (1983). Antitu-
mour activity of yoghurt components. J. Food. Prot. 46:8–11.
Reddy, G. V. and Shahani, K. M. (1971). Isolation of an antibiotic from lacto-
bacillus bulgaricus. J. Dairy Sci. 54:48.
Reddy, G. V., Shahani, K. M., Friend, B. A., and Chandan, R. C. (1983). Natu-
ral antibiotic activityof lactobacillus acidophilus and bulgaricusIIIProduction
and partial purification of bulgarican from lactobacillus bulgaricus. Cult.
Dairy Prod J. 18:15–19.Reid, G., Gan, B. S., She, Y. M., Ens, W., Weinberger, S., and Howard, J. C.
(2002). Rapid identification of probiotic Lactobacillus biosurfactant proteins
by Protein Chip tandem mass spectrometry tryptic peptide sequencing. Appl.
Environ. Microbiol. 68:997–980.
Reuter, G. (1990). Bifidobacteria cultures as components of yoghurt like prod-
ucts. Bifidobacteria Microflora. 9:107.
Roberfroid, M. B. (1999). What is beneficial for health? The concept of func-
tional food. Food Chem. Toxicol. 37:1039–1041.
Rossi, J. and Clementi, F. (1983). Fermented beverages obtained from uncon-
ventional substrates. Scienza. Tec.latt-casear. 34:332–335.
Saavedra, J. M., Bauman, N. A., Oung, I., Perman, J. A., and Yolken, R. H.
(1994). Feeding of bifidobacterium bifidum and streptococcus thermophilus
to infants in hospital for prevention of diahhroea and shedding of rotavirus.
Lancet. 344:1046–1049.
Salminen, S., Deighton, M., Benno, Y., and Gorbach, S. L. (1998). Lactic acidbacteria in health and disease. In: Lactic Acid Bacteria: Microbiology and
Functional Effect,pp. 211–253.Salminen, S. and Von wright,A., Eds.,Marcel
Dekker Inc., New York.
Sandine, W. E. (1985). The streptococci: Milk products. In: Bacterial Starter
Cultures for Foods, pp. 25–40. CRC Press. Inc., Boca Raton, Florida.
Sandine, W. E., Muralidhara, K. S., Elliker, P. R., and England, D. C. (1972).
Lactic acid bacteria in food and health: a review with special references
to enteropathogenic Escherichia coli as well as certain enteric diseasesand
their treatment with antibiotics and lactobacilli. J. Milk Fd. Technol. 35:691–
702.
Sarkar, S. and Misra, A. K. (2001). Characteristics of dietetic yoghurt. Indian.
J. Dairy Biosci. 12:76–79.
Schleifer, K. H., Kilpper-Balz, R., Collins, M. D., and Fischer, W. (1985).
Transfer of streptococcus lactis and related streptococci to the genus lacto-
coccus.gen. nov.Systematic. Appl. Microbiol. 6:183–195.
Servin, A. L. (2004). Antagonistic activities of lactobacilli and bifidobacteria
against microbial pathogens. FEMS Microbiology Reviews 28(4):405–440.
Shah, R. K., Prajapati, J. B., and Dave, J. M. 1986. Innovations in Acidophilus
products technology. Indian Dairy Man. 38:21–23, 26–29.
Shahani, K. M. and Chandan, R. C. 1979. Nutritional and healthful aspects of
cultured and culture containing dairy foods. J. Dairy. Sci. 62:1685–1700.
Shahani, K. M., Friend, B. A., and Bailey, P. J. (1983). Antitumour activity of
fermented colostrom and milk. J. Food. Prot. 46:385–386.
Shahani, K. M., Vakil, J. R., and Kilara, A. (1977). Natural antibiotic activi-
tyof lactobacillus acidophilus and bulgaricus II Isolation of acidophilin from
L.acidophilus. Cult. Dairy Prod. J. 12:8.
Shalo, P. L. (1987). Pastoral method of handling and preserving milk. In: Dairy
development in eastern Africa. Proc. IDF Seminar. Nairobi 9–13 March,
1987. IDF/FIL Bull. No. 221, pp. 110–112.
Sheu, T. Y. and Marshall, R. T. (1993). Microencapsulation of lactobacilli in
calcium alginate gels. J. Food Sci. 54:557–107561.Singh, S. 2001. Health beverages from milk permeate. Paper presented in XI
CAS course. DT Division, NDRI Karnal, India, December 12–January 10,
2001.
Singh, J. and Sharma, D. K. 1983. proteolytic breakdown of casein and its
fraction by lactic acid bacteria. Milchwissenchaft. 38:148–149.
Singh, S., Singh, A. K., and Patil, G. R. Whey utilization for health beverages.
Ind.n Food Ind.. 21(4), 38–41.
Snoeren, R. H. M., Damman, A. J., and Klok, H. J. (1981). De viscositet van
ondermelkconcentraat. Zuivelzicht. 73:887–889.
Speck, M. L. 1976. Interactions among lactobacilli and man. J. Dairy. Sci.
59(2):338–343.
Spinnler, H. E. and Corrieu, G. (1989). Automatic method to quantify starter
activity based on pH measurement. J. Dairy Res. 56:755–764.Steenson, L. R., Klaenhammer, T. R., and Swaisgood, H. E. (1987). Calcium
alginate-immobilized cultures of lactic streptococci are protected from bac-
teriophages. J. Dairy Sci. 70:1121–1127.
Sung, H. H. (1997). Enhancing survival of lactic acid bacteria in ice cream by
natural encapsulation. Diss. Abstr. Int. 13:5407.
Surawicz, C. M., Elmer, G. W., Speelman, P., Mcfaraland, L., Chinn, J.,
and Belle, G. (1989). Prevention of antibiotic associated diahhroea by
Saccharomyces boulardii. A perspective study. Gastroenterol. 84:2072–
2078.
Szczesnik,A. S. (1979).Classificationof mouthfeelcharacteristics of beverages.
Food Texture and Rheology, pp. 1–20. Academic Press, London.
Temmermman, R., Huys, G., and Seings, J. (2004). Identificaton of lactic acid
bacteria: culture dependent and culture independent methods. Trends in Food
Sci. Technol. 15:348–359.
Toranto, M. P., Medici, M., Perdigon, G., Ruiz Hardago, A. P., and Valdez, G. I.(1998). Evidence for hypocholesterolomic effect of L. reuteri in hypocholos-
terolaemic mice. J. Dairy Sci. 81:2336–2340.
Torriani, S., Gardini, F., Guerzoni, M. E., and Dellaglio, F. (1996). Use of
response surface methodology to evaluate variables affecting the growth and
acidification characteristics of yoghurt cultures. Int. Dairy J. 6:625–636.
Towler, C. (1984). Sedimentation in cultured milk beverage. N.Z. J. Dairy Sci.
and Technol. 19(3):205–211.
Trompa, H., de Kruifa, C. G., van Eijkb, M., and Rolin, C. (2004). On the mech-
anism of stabilization of acidified milk drinks by pectin. Food Hydrocolloid.
18:565–572.
Urala, N., Arvola, A. and Lähteenmäki, L. (2003). Strength of health re-
lated claims and their perceived advantage. Int. J. Food Sci. Technol.
38(7):815–826.
Usacheva, V. A., Gus’kova, L. D., Volkova, L. G., Alekseeva, N. Yu.,
Fil’chakova, S. A., and Sochneva, L. G. (1990). USSR Patent SU1 584 876.
Usman and Hosono, A. (2000). Effect of administration of L.gasseri on
serum lipids and fecal steroids in hypercholesterolaemic rats. J. Dairy Sci.
83:1705–1711.
Vakil, J. R. and Shahani, K. M. (1965). Partial purification of antibacterial
activity of lactobacillus ac idophilus. Bact. Proc. 9.
Varnam, A. and Sutherland, J. (1994). Milk and Milk Products Technology,
Chemistry and Microbiology. Chapman and Hall, London.
Walker, D. R. and Gilliland, S. E. (1993). Relationship among bile tolerance,
bile salts deconjugation and assimilation of cholesterol by L.acidophilus. J.
Dairy Sci. 76:956–961.
Watt, B. K. and Merril, A. L. (1963). Composition of Foods. Agricultural
Handbook No. 8, USDA, Washington, DC.
Wood, J. B. J. (1997). Microbiology of Fermented Foods. Blackie Academic
and Professional, London.
Wood, J. B. J. andHolzaphel,W.H. (1995). TheGenera of LacticAcidBacteria.
Blackie Academic and Professional, London.Wouters, J. T. M.,Ayad, E. H. E., Hugenholtz,J., and Smith, G. (2002).Microbes
from raw milk for fermented dairy products. Int. Dairy J. 12:91–109.
Ziemer, J. C. andGibson,G. R. (1998).An overview of probiotics, prebiotics and
synbiotics in the functional food concept: Perspectives and future strategies.
Int. Dairy J. 8:473–479.