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Whey protein

  • Shri. Sant Gajanan Maharaj College of Pharmacy Buldana
ISSN 2249-5975
Vol 1 / Issue 2 / Jul 2011
Publication of Society of United Life Sciences, India
Research Journal
Scholars' Research Journal / Jul-Dec 2011 / Vol 1 / Issue 2 69
Review Article
Whey protein
Hemant H Gangurde, Mayur A Chordiya, Pooja S Patil, Nayana S Baste
Department of Pharmaceutics, SNJB’s S.S.D.J., College of Pharmacy, Neminagar, Chandwad, Nasik, Maharashtra, India
Whey is one of the two proteins in cow’s milk, making approximately 20%, and casein is the other protein that forms
approximately 80% of the total protein content. Whey proteins refer to a group of individual proteins or fractions that
separate out from the casein during cheese making. These fractions are puried to different concentrations, depending
on the end composition desired, and can vary in their content of protein, lactose, carbohydrates, immunoglobulin,
minerals, and fat. The most common forms of whey protein used in high protein bars, beverages, and supplements
are the concentrate (WPC) or the isolate (WPI). Protein Digestibility Corrected Amino Acid Score (PDCAAS) is a new
system that determines the protein quality and is utilized to establish the percent daily value for the nutrients on food
labels. Whey protein is a complete, high-quality protein with a rich amino acid (AA) prole. It contains the full spectrum
of AAs including essential AAs (EAAs) and branched-chain AAs (BCAAs) which are important in tissue growth and
repair. Leucine is a key BCAA in protein synthesis and has recently been identied as playing a critical role in insulin,
muscle building, and glucose metabolism. The EAAs and BCAAs in whey protein are present in higher concentrations
compared with other proteins such as soy, meat, and wheat; they are also efciently absorbed and utilized. Whey protein
also has some important benets like it reduces the symptoms of chronic fatigue and its major use is in the HIV and viral
infections as it increases the immunity. The review discusses the history, types, forms, side effects and applications of
whey protein in human health.
Key Words: Branched chain amino acids, chronic fatigue syndrome, protein digestibility corrected amino acid score, whey
Proteins are organic compounds made of amino
acids arranged in a linear chain and folded into a
globular form. They are also known as polypeptides.
The amino acids in a polymer are joined together
by the peptide bonds between the carboxyl and
amino groups of adjacent amino acid residues. The
sequence of amino acids in a protein is dened by
the sequence of a gene, which is encoded in the
genetic code. There are 20 common amino acids.
Amino acids share a common structure except for
one chemical group (R, side chain) attached to the
central carbon atom. The 20 different R groups give
the amino acids their individual characteristics.
Amino acids join up to make peptide chain. The
words peptide and protein actually refer to the
same structure; however, peptide is generally used
for shorter chains of amino acids and protein for
longer chains. Proteins made up of more than one
polypeptide chain, as many of the large ones are, are
called oligomeric.[1]
Proteins can be classied based upon
Structure ,enzymes, receptor action and functions
[Table 1]. Proteins are derived from various sources
such as milk, meat, egg, soy, wheat, etc [Table 2].
Milk has two proteins: casein and whey protein.
Whey protein is more soluble than casein and also has
a higher quality rating. Whey is highly bioavailable
and boasts having the highest biological value (BV)
of any protein source. Therefore, a whey product may
be an excellent choice for those looking for a protein
product that can be readily used by the body to build
mass. Casein makes up the other 80% of protein in
milk and is often considered to be the slowest acting
form of protein because it takes longer than whey or
soy protein to digest. Eggs are often considered to be
one of the healthiest forms of protein because they
contain virtually all of the amino acids used in the
human body. Since egg protein contains no dairy, it is
Address for correspondence: Mr. Hemant H Gangurde, Department of Pharmaceutics, SNJB’s S.S.D.J. College of Pharmacy, Neminagar, Chandwad –
423 101, Nasik, Maharashtra, India. E-mail:
Access this article online
Quick Response Code:
DOI: 10.4103/2249-5975.99663
Gangurde, et al.: Whey protein
70 Scholars' Research Journal / Jul-Dec 2011 / Vol 1 / Issue 2
often used by those who are allergic to lactose, even
though low lactose whey protein is available.
Soy protein is a healthy and vegan appropriate way of
getting protein. It is comparable in quality to casein,
but digests within 2–4 hours of consumption, making
it an ideal addition to meals. Soy protein is known to
be a good antioxidant and soy products often contain
other healthy vitamins, but recent medical debates
have questioned the possibility of several downsides
to ingesting large amounts of soy.
Meat protein is a general classication for all forms
of protein found in meat. These types of protein are
usually slow-burning and incomplete, but they offer a
good source of nutrition if ingested along with other
forms of protein. Turkey and salmon are two of the
best forms of lean protein to be found in meat, as they
have lower fat contents and more balanced forms of
pro types of whey protein.[2]
Whey Protein
Whey protein is a high-quality protein powder
from cow’s milk. Milk has two proteins: casein
(approximately 80%) and whey protein (approximately
20%) [Figure 1a-b].[5,6] Whey contains less than 1%
proteins comprising mainly β-lactoglobulin (β-LG),
α-lactalbumin (α-LA), bovine serum albumin (BSA),
immunoglobulins and proteose peptone, as well as
several minor proteins including lactoferrin, lactollin,
glycoproteins, lactoperoxidase and transferrin.[7] Whey
proteins are the proteins remaining soluble at pH 4.6
and 20°C after the removal of caseins from milk. Two
primary types of whey are available as whey protein
sources. Acid whey is produced by the generation or
direct addition of acid and results in the precipitation
of caseins. Sweet whey comes from rennet coagulated
cheese when caseins are removed.[8] Advances in
processing technologies have enabled the purication
and separation of whey proteins which are sold
as concentrate (WPC) or isolate (WPI) containing
35–80% and >90% proteins, respectively.[9] The
production of WPC begins with a clarication step
where centrifugation removes small cheese and casein
particles. Then, ultraltration, a physicochemical
separation technique in which a pressurized solution
ows over a porous membrane, allows the selective
separation of whey proteins from lactose, salts, and
water under mild conditions of temperature and pH.
Dial ltration can be applied to further increase the
protein purity by continuously adding water to the
ultra ltration retentive stream. Finally, spray drying
is used to yield a product with greater than 95% total
solids. On the other hand, ion exchange fractionation
processes are used for the manufacture of WPI. Whey
proteins have a net positive charge at pH values lower
than their isoelectric point (pH 5.2) and behave as
cations that can be absorbed on cation exchangers. At
pH values above their isoelectric point, whey proteins
Figure 1: (a) Composition of whole milk. (b) Composition of whey and
casein protein in milk[5]
Table 1: Types of protein depending on their
Protein types Function Examples
Structural Give shape and size to
the cell or organelles
Actin, tubulin
Enzymes Catalyze biological
Tyrosine adenylate
Receptors Bind to other molecule
and transmit signals
Glutamate R.,
steroid R.
Other functional
Have specic functions Antibodies, nuclear
factor, neuropeptides
Table 2: Chemical constituent of various proteins and their biological value[3,4]
corrected amino
acid source
digestibility %
Whey protein 1.00 1.14 3.2 100 99
Whole egg 1.00 1.21 3.8 88-100 98
Casein 1.00 1.00 2.5 80 99
Soy protein
1.00 0.99 2.2 74 95
Beef protein 0.92 0.94 2.9 80 98
Wheat gluten 0.25 0.47 NA 54 91
Gangurde, et al.: Whey protein
Scholars' Research Journal / Jul-Dec 2011 / Vol 1 / Issue 2 71
have a net negative charge and behave as anions that
can be absorbed on anion exchangers. Once proteins
are absorbed onto the resins, a change in the pH of
the mobile phase is used to detach them, followed
by ultraltration, dial ltration, and drying. WPIs are
characterized by high protein and low lactose and
lipid concentration.[10]
Whey protein is the collection of globular proteins
isolated from whey, a by-product of cheese
manufactured from cow’s milk. It is typically a
mixture of β-LG (~65%), α-LA (~25%), and serum
albumin (~8%), which are soluble in their native
forms, independent of pH. The protein fraction
in whey (approximately 10% of the total dry
solids within whey) comprises four major protein
fractions and six minor protein fractions. The major
protein fractions in whey are β-LG, α-LA, BSA, and
immunoglobulin. The above composition has been
summarized in Table 3.[11]
Whey is now used in various products like infant
formulas, food supplements, sport bars, and beverages
to meet a variety of health goals for people of all ages.
It has been proven that the intake of whey in the form
of liquid was started by the Greeks. Around 2500
years ago, Hippocrates recommended some drinks to
enhance the immune system, power, and the muscle
growth rate of the body. These old time energy
drinks were known as serums. Serums were rich in
lactose, minerals and fast absorbing proteins, which
made them effective in enhancing the performance
of the body. In the late 16th century, Switzerland was
the place where the importance of whey protein was
rediscovered. It was noticed by the farmers that the
pigs which slopped on whey developed faster than
the pigs which slopped on something else. So, the
farmers started drinking the whey themselves. When
they noticed improvement in their health, the word
spread quickly throughout the land. Whey was an
important by-product of cheese production from the
rst commercial cheese factory in the city of New
York. This factory generated large amount of whey
which was very difcult to dispose. Due to this, the
cheese makers used to dump large amount of whey
into lakes and rivers or they used it for irrigating
crops. Farmers soon realized that it was not the best
use of the whey which was produced, and hence they
started mixing the liquid whey with barley or grain
to produce high-protein animal feed. In the past 20
years, whey protein has changed from being a waste
product of cheese making to a highly valued product
rich in nutritional and functional properties.[14,15]
Whey is left over when milk coagulates and contains
everything that is soluble from milk. It is a 5%
solution of lactose in water, with some minerals and
lactalbumin. It is removed after cheese is processed.
The fat is removed and then is processed for
human foods.[5] Processing can be done by simple
drying, or the protein content can be increased by
removing lipids and other non-protein materials
[Figures 2 and 3].[16] For example, spray drying after
membrane ltration separates the proteins from
Whey can be denatured by heat. High heat (such
as the sustained high temperatures above 72°C
associated with the pasteurization process) denatures
whey proteins. While native whey protein does not
aggregate upon renneting or acidication of milk,
denaturing the whey protein triggers hydrophobic
interactions with other proteins and the formation of
protein gel.[16] Heat-denatured whey can still cause
allergies in some people.[17]
Gelation is an important functional property of
whey proteins. Gelation is caused by the action of
heat, pressure, and divalent cations. Whey protein
solutions are prepared by dissolution of the powder in
deionized distilled water and stirring with a magnetic
stirrer for 90 min at room temperature in beakers at
a concentration of 10%. The pH of the solutions is
adjusted using 1 N HCl and 1 N NaOH. Beakers are
Figure 2: Extraction process of whey protein
Table 3: Chemical constituents of whey
Chemical constituent Percentage
α-Lactalbumin 11.3–16.5
b- Lactalbumin Lactoglobulin 37.9–49.0
IgG 5.0–8.0
Glycomacropeptides 15.0–20.0
Lactoferrin 1.3–1.8
Bovine serum albumin 3.0–5.0
Gangurde, et al.: Whey protein
72 Scholars' Research Journal / Jul-Dec 2011 / Vol 1 / Issue 2
placed in a water bath heated at 80°C for 30 min. After
the heat treatment, the solutions are rapidly cooled
to 10°C in an ice bath and stored in a refrigerator
overnight. Gels are placed at room temperature 2
hours before texture analysis. The whey proteins are
compact globular proteins with a relatively uniform
distribution of a chain of polar, non-polar, uncharged
and charged remains of amino acids.[18] Whey can be
further processed into spray-dried products like, for
instance, WPCs, WPIs or whey protein hydrolysates
This can further be proven using the Protein
Digestibility Corrected Amino Acid Score (PDCAAS)
which is a new system that determines the protein
quality and is utilized to establish the percent daily
value for the nutrients on food labels. The maximum
PDCAAS is 1.00, and whey protein has a PDCAAS
of 0.99–1.00. Whey protein contains little to no fat,
lactose, or cholesterol, and is a rich source of essential
amino acids.[19] PDCAAS values changes with the
change in type of protein shown in Table 4.
Amino Acids in Whey Protein
Whey protein is loaded with the essential and non-
essential amino acids with few carbohydrates and
little fat content. It contains the amino acid cysteine
which can be used to make glutathione (GSH).
However, this amino acid is not essential for the
synthesis of GSH and some studies have suggested
that the amount of cysteine in the diet may have little
effect on GSH synthesis. However, another study
suggested that large amounts of whey protein can
increase cellular GSH levels. GSH is an antioxidant
that defends the body against free radical damage and
some toxins, and studies in animals have suggested
that milk proteins might reduce the risk of cancer.[20,21]
Major forms of whey protein
Whey protein concentrate
Whey protein isolate
Hydrolyzed whey protein
Whey protein concentrates
WPCs are available in various protein concentration
levels such as 34% (WPC34), 50% (WPC50), or 80%
(WPC80). Concentrates contain a low level of fat
and cholesterol but, in general, have higher levels of
bioactive compounds, and carbohydrates in the form
of lactose. 70–80% protein content is more available as
protein powder supplement.[22,23]
Whey protein isolate
It is the purest form of whey protein and contains
90% or greater protein with minimal lactose (<1%)
and virtually no fat and is of high cost. Isolates are
processed to remove the fat and lactose, but are
usually lower in bioactive compounds.[23]
Hydrolyzed whey protein
Hydrolysates are predigested, partially hydrolyzed
whey proteins that, as a consequence, are more
easily absorbed, but their cost is generally higher.
Highly hydrolyzed whey may be less allergenic than
other forms of whey. They are very bitter in taste.
Hydrolysis process breaks down protein chains into
small fractions called peptides [Table 5].[6]
Whey Protein
Isolation of whey protein
WPI is generally the highest quality of whey
supplement, and therefore usually the most
expensive. These products “isolate” the whey protein
by going through the most advanced ltering process
to remove carbohydrates and fats. Thus, they have the
Dairy Milk
Curds Whey
Cheese Casein
Whey Protien
Whey Protein
Whey Protein
Blend(WPC +
Whey Protein
Blend(WPC +
Whey Protein
Figure 3: Steps involved in manufacturing whey protein
Table 4: PDCAAS of various key proteins
Protein source PDCAAS
Whey protein 1.14
Casein 1.0
Milk protein isolate 1.0
Soy protein isolate 1.0
Egg white powder 1.0
Ground beef 1.0
Canned lentils 0.52
Peanut meal 0.52
Wheat gluten 0.25
Gangurde, et al.: Whey protein
Scholars' Research Journal / Jul-Dec 2011 / Vol 1 / Issue 2 73
highest percentage of protein compared to other whey
products. The whey isolate supplements are very
quickly absorbed and are therefore very fast-acting.
WPCs are products that do not go through such an
advanced ltering process as the whey isolate. Hence,
they generally contain about 10–15% less protein and
most likely include some fats and carbs. Some WPC
products also have some whey isolate blended in.[25,26]
WPI has been further differentiated into three types:
• Micro-ltered undenatured isolate
• Undenatured WPI
• WPI bars
Pharmacology of Whey Protein
A protein may have all of the amino acids required,
but this becomes immaterial if the protein cannot be
absorbed easily. BV is a percentage score showing
how much of the protein is absorbed by the body.
Whey protein, along with whole egg, has a perfect
score of 100. In addition to the complete absorption
level, it is important that the protein be absorbed as
fast as possible to aid recovery after training. Whey
protein is digested exceptionally quickly, which
makes it ideal as a post-workout liquid meal. The
biggest of an issue this is for you, the more important
the purity of the protein. Again, WI ranks above any
other protein in this area. On a more practical level,
different proteins have a different taste, but many
people quite enjoy the mild, milky taste of whey
protein isolate.[5]
Benefits of Whey Protein
Whey protein contains the highest concentration (23–
25%) of branched-chain amino acids (BCAAs) of any
single protein source. This BCAA content is important
to athletes because BCAAs are an integral part of
muscle metabolism and are the rst aminos sacriced
during intense exercise and muscle catabolism
Whey also has the ability to enhance endogenous
GSH production. GSH is the body’s most powerful
naturally occurring antioxidant and also plays a role
in immune system support.
Whey protein contains quadrapeptides, which have
been shown to have opioid effects. This is another
powerful functional property that may help decrease
the sensation of muscle soreness following intense
weight training.
Due to its excellent amino acid prole, solubility
and digestibility, whey has a very high BV. BV is a
measure of how well a protein is utilized by the body.
One of the more interesting functional properties
of whey protein is its ability to help stimulate IGF4
Whey has been shown to reduce cholesterol by
inhibiting low-density lipoprotein (LDL) production.
Whey protein has antibacterial, anti-viral activity; also,
it reduces liver damage, improves immune system
function, digestive function, and blood pressure, and
reduces gastric mucosal injury.
Whey Versus Soy Protein
Both soy protein and whey protein are helpful in
building body muscle. Soy proteins and whey proteins
are competitors. People, unknown about muscle
building supplements, have wondered which protein
is better for their individual workout needs and what
the difference is between the two. Soy protein is
taken from soybeans and contains a high amount of
amino acids. It has been found to lower cholesterol,
Table 5: Uses of different types of whey protein (percentages by weight)[24]
Product Protein
Fat Applications
Whey powder 11–14.5% 63–75 1–1.5% Used in breads, bakery and snack items and dairy
Whey protein
25–89% (most
commonly available as
4–52 1–9% (as protein
concentration increases, fat,
lactose and mineral content
The most common and affordable form of whey.
Used in protein beverages and bars, bakery and
confectionary products, dairy foods and other
nutritional food products
Whey protein
90–95% 0.5–1 0.5–1% Used in protein supplementation products,
protein beverages, protein bars, other nutritional
food products
Hydrolyzed whey
protein concentrate
>80% (hydrolysis used
to cleave peptide bonds)
<8 <10% (varies with protein
Used in sports nutrition products
Hydrolyzed whey
protein isolate
>90% 0.5–1 0.5–1% Highly digestible form containing easy-to-digest
peptides that reduce risk for allergic reaction in
susceptible individuals commonly used in infant
formulas and sports nutrition products
Gangurde, et al.: Whey protein
74 Scholars' Research Journal / Jul-Dec 2011 / Vol 1 / Issue 2
Table 6: Differences between soy and whey
Soy protein Whey protein
Soy protein comes from
soybeans, which are legumes (a
source of carbohydrates)
Whey protein is made out of
natural sources as a diary by-
Soy protein does not provide an
excellent source of glutathione
Whey protein provides an
excellent source of glutathione
Does not contain plenty of
amino acids
Contains plenty of amino acids
Is the best for those women
who are vegetarians and for
body building
Is not the best source for the
ght heart disease, and speed up metabolism of the
thyroid, helping the body become leaner. Whey
protein is taken from milk as a diluted by-product
of cheese. It has been shown to be antibacterial, and
to assist in maintaining correct body weight, regulate
blood pressure, improve the immune system, and
improve the digestive system’s efciency [Table 6].[28]
In a study by a scientist, a mixture of amino acids
was administered in two groups which showed
almost identical effects to those of whey protein. Soy
protein is naturally high in amino acids which have
effects similar to those of whey protein.[29] In another
study, whey and soy proteins were administered to
two groups. The groups were both given the same
exercise routines. At the end of the study, the groups
which took the whey protein and soy protein, both
showed improvements in lean body mass. The only
difference in the two groups was that the group
which ingested the soy protein showed avoidance of
two negative effects like plasma radical scavenging
capacities in whey and training alone groups, while
the myeloperoxidase values rise that the whey protein
group suffered.[30]
Side Effects
Many people cannot tolerate nor have allergic
reactions to milk or other dairy products that contain
lactose. These people have what is called lactose
intolerance. Such lactose intolerant people may
develop allergic reactions after having whey protein
which is made from milk. However, two forms of
this protein – WPIs and WPHs – are processed to
remove the fat and lactose, and therefore they might
not cause allergy to such people who cannot tolerate
milk products. Whey protein consumed in very high
quantities can affect kidney functions negatively.
Extremely high doses of whey protein exert
unbearable pressure on liver and may lead to liver
damage. Again, if whey protein is taken excessively,
it can lead to an imbalance of minerals in the bones,
causing loss of bone mineral density. This can lead
to osteoporosis. Another probable side effect of
consuming whey protein is that it can lead to an
increase in the pH of blood. Excess protein in the
blood makes it difcult for the kidney to metabolize
Muscle building
Protein supplements are being used every day by
both old and young people. Most of these people are
avid exercisers who work out and tear their muscles
apart on a daily basis. Protein is what helps the body
build its muscles back together, and therefore has a
major role in making the human body stronger.[31]
Whey protein contains the highest percentage of
protein source and BCAAs. BCAAs help stimulate
protein synthesis or muscle growth which is
important in muscle building and muscle retention.
Whey protein also protects the degradation of muscle
protein. Whey is necessary in building blocks to
produce the amino acids that the body uses to build
lean muscle tissue.
[32,33] Whey is also a fast acting
protein, which means that it is absorbed quickly into
the bloodstream. It is widely believed that drinking
a protein shake that contains whey shortly after a
training session can speed up muscle recovery by
making the essential and BCAAs readily available to
the muscles. Low BCAA levels contribute to fatigue
and they should be replaced in 1 hour or less following
exercise or participation in a competitive event. Whey
protein is highly favored by bodybuilders because it
provides the necessary building blocks to produce the
amino acids that the body uses to build lean muscle
tissue. It is best taken in powder form mixed in
juice or milk, spread throughout the day to maintain
positive nitrogen. Whey protein is a relatively safe
supplement, but no more than 30 g of protein should
be taken at one sitting as excessive single doses could
overload the liver. The safety of whey protein has
been well documented in many scientic studies, and
there is clear proof that taken consistently, coupled
with regular exercise, it will result in meaningful
Weight management
Whey protein can play an important role in weight
management. Specic factors in whey protein like
leucine are being investigated for their ability to
promote weight loss by increasing satiety, inuencing
glucose homeostasis, and maintaining lean body mass
and promoting fat loss.[35] Whey has been shown to be
effective in increasing satiety and modulating energy
intakes, which may result in a loss of body fat and
weight.[36] Several studies have shown whey protein
to be more effective than soy, egg, and meat proteins
in suppressing food intake. For these reasons,
Gangurde, et al.: Whey protein
Scholars' Research Journal / Jul-Dec 2011 / Vol 1 / Issue 2 75
incorporating whey protein into the diet could be an
ideal solution for the many consumers interested in
high-protein and moderate carbohydrate diets.[37,38] C.
In diseased condition
Chronic Fatigue Syndrome
Chronic fatigue syndrome (CFS) has been linked to
abnormalities found in both hormonal and cellular
immunity. Tests consistently indicate that those
diagnosed with CFS have an impaired lymphocyte
(T-cell) response. The ability of lymphocytes to react
to an immune challenge is directly related to their
Glutathione (GSH) status. GSH is arguably the most
important water-soluble antioxidant found in the
body. It is a tripeptide made up of the amino acids
l-cysteine, l-glutamine, and glycine. It is also essential
for aerobic muscular contractions, an undesirable
competition for GSH precursors between the immune
and muscular systems may develop. Whey protein
is the most effective way to deliver precursors for
GSH synthesis. Whey may be especially effective for
people suffering from CFS.[39,40]
Viruses and HIV
Whey has the ability to suppress the viral load and
improve immunity in people with HIV. HIV infection
is characterized by increased oxidative stress, and a
systemic deciency of GSH is known to be essential
for immunity, oxidative stress, and general well-being.
The amount of GSH present is directly related to
lymphocyte reactivity to a challenge, which suggests
that intracellular GSH levels are one way to modulate
immune function. A large amount of available
cysteine is used for the synthesis of GSH. Different
strategies to supplement cysteine are being used to
increase GSH levels in HIV-infected individuals. For
example, N-acetyl cysteine (NAC) and alpha lipoic
acid are well known for increasing the levels of
GSH. In GSH-decient patients with advanced HIV
infections, short-term oral supplementation with
whey protein increases plasma GSH level.[41-44]
Blood Pressure
Hypertension has also been linked to an enzyme
secreted by the kidneys called angiotensin converting
enzyme (ACE). ACE has been clinically associated
with the rennin angiotensin system, which regulates
peripheral blood pressure. By blocking the effects of
ACE, blood pressure can be brought under control.
Whey peptides, known as lactokinins, have recently
been shown to be mild ACE inhibitors.[5]
Gastrointestinal System
Whey plays an important role in the protection
of the gastrointestinal system. In one experiment,
gastric mucosal injury was induced by either alcohol
(ethanol) or water immersion restraint stress where
the rats are put in water at 28°C for 7 hours. a-LA,
one of the chemical constituents of whey, has marked
antiulcer activity, suggesting that a-LA intake may
serve to protect against gastric mucosal injury in part
through endogenous prostaglandin synthesis.[45]
Kidney Diseases
Whey has extremely high Protein Efciency Ratio
which is important in conditions like renal failure
where protein intake must be limited and it is most
prudent to consume the highest quality proteins (like
WPI and egg white proteins) rather than lower-quality
proteins (like red meat and dairy) that produce
more problematic metabolic waste by-products and
In Males
For promoting weight loss, increasing the muscle
mass, healthy aging and athletes and body builders,
whey protein is the most easily and quickly absorbed
protein available. It helps build muscle by stimulating
maximum protein synthesis.[5,46]
In Females
The second most abundant component in whey
protein is a-LA, which is one of the main whey
proteins in human breast milk. They are not allergic
to dairy proteins. For tatting women protein is
essential for proper fetal and infant development,
particularly brain development, and helps prevent
gestational diabetes.[46]
In Children
Whey protein helps stabilize children’s blood sugar
and increases the production of feel-good brain
chemicals that help increase mental clarity and focus.
It also provides the protein essential for growing
bodies, particularly brain.[47]
In Adults and Elderly People
As a person get older, his/her body becomes less
efcient in absorbing protein. Whey protein is the
most easily absorbed protein available. It can reverse
the aging process and rebuild the immune system. It
can ensure that you are rarely, if ever, sick, and that
you will begin to look and feel years younger.[48]
Whey protein is a pure, natural, high-quality protein
from cow’s milk. It is a rich source of all of the
essential amino acids needed on a daily basis by the
body. In its purest form, as WPI, it contains little to no
fat, lactose, or cholesterol. Whey protein has one of the
highest PDCAAS (a measure of protein bioavailability)
and is more rapidly digested than other proteins such
as casein. Whey is available in three major forms,
i.e. WPCs, WPIs or WPHs. WPI has been further
Gangurde, et al.: Whey protein
76 Scholars' Research Journal / Jul-Dec 2011 / Vol 1 / Issue 2
differentiated into micro-ltered undenatured isolate,
undenatured WPI, and WPI bars. Whey proteins are
both easily digested and have excellent metabolic
efciency, giving the protein a high BV. They contain
the highest percentage of protein source and BCAAs.
BCAAs help stimulate protein synthesis or muscle
growth, which is important in muscle building and
muscle retention. Whey may also support a healthy
response to stress and help maintain healthy levels of
the brain’s neurotransmitters. There are some great
benets of the whey protein on HIV infected person.
It is benecial in conditions like hepatitis, blood
pressure, chronic fatigue, kidney diseases, for weight
loss, and for an increase in the immune power. Unlike
many proteins, whey offers a valuable combination of
proven scientic efcacy and pleasant consumption.
In short, whey protein has all that we want.
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How to cite this article: Gangurde HH, Chordiya MA, Patil PS,
Baste NS. Whey protein. Scho Res J 2011;1:69-77.
Source of Support: Nil, Conict of Interest: None declared.
... Its volume as a surplus is considered high, because 9 L of whey is produced for every 1 kg of cheese [8]. However, it is made up of 6.5% of total solids, of which 0.8% is protein (20% of all milk protein), 0.5% fat and 4.5% lactose, in addition to minerals such as calcium [9,10]. The main proteins present are β-lactoglobulin, α-lactalbumin, casein, immunoglobulins, lipoprotein, bovine serum albumin (BSA), lactoferrin, lactoperoxidase, bioactive peptides and essential amino acids [9,11]. ...
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The objective of this study was to investigate the nutritional quality of bovine colostrum and whey mixtures. Five whey with bovine colostrum formulations were prepared (90:10; 80:20; 70:30; 60:40 and 50:50 whey:colostrum v:v) to be subjected to low-temperature pasteurization (63°C to 65°C for 30 minutes) and freeze-drying. The samples underwent chemical composition characterization, fatty acid profile analysis, determination of contamination by Enterobacteriaceae, pH, and Dornic acidity measurements before and after vat pasteurization. The amount of protein, fat, total solids, defatted dry extract, Brix and density increased as the bovine colostrum concentration increased. The level of saturated fatty acids and the thrombogenicity and atherogenicity indices reduced, while unsaturated fatty acids increased as the level of added bovine colostrum increased. The low-temperature pasteurization of the formulations was possible and effective, eliminating contamination by Enterobacteriaceae in the samples. Mixing bovine colostrum and whey reduced the colostrum viscosity, allowing a successful pasteurization procedure. Due to colostrum composition, the formulations yielded a higher nutritional value when compared to whey alone. The parameters applied in the formulation of mixtures of bovine colostrum and whey resulted in valuable ingredients for preparing novel dairy products.
Climate changes, drought, the salinity of water and soil, the emergence of new breeds of pests and pathogens, the industrialization of countries, and environmental contamination are among the factors limiting the production of agricultural products. The use of chemicals (in the form of fertilizers, pesticides and fungicides) to enhance products against biotic and abiotic stresses has limitations. To eliminate the effects of agricultural chemicals, synthetic agrochemicals should be replaced with natural substances and useful microorganisms. To be more effective and efficient, plant biocontrol bacteria need a coating layer around themselves to protect them from adverse conditions. Whey protein, a valuable by-product of the cheese industry, is one of the important natural polymers. Due to its high protein content, safety, and biodegradability, whey can have many applications in agriculture and encapsulation of bacteria to resist pests and plant diseases. This compound is a rich source of amino acids that can activate plant defense systems and defense enzymes. Considering the amazing potentialities of formulation whey protein, this review attends to the efficiency of whey protein as coating layers on fruit and vegetables and in the packaging system to increase the shelf life of agricultural products against phytopathogens.
Functional foods are defined as foods and ingredients that exhibit health benefits beyond their nutritional value. Research on functional foods is increasing rapidly as they may help prevent and manage some non-communicable diseases. Whey proteins are recognized as a high-quality nutrient source and known to contain some bioactive components. They are rich in essential amino acids such as cysteine, branched-chain amino acids such as leucine, valine, and isoleucine, and bioactive peptides. Whey proteins look promising as a potential functional food, given its antioxidant, anti-inflammatory, blood pressure lowering, anti-obesity, and appetite suppressing effects that is discussed in the literature. Whey proteins also show functional properties that play an essential role in food processing as an emulsifier, fat-replacer, gelling and encapsulating agent and are known to improve sensory and textural characteristics of food. This review focuses on the functional food aspects of whey proteins, associated health effects, and current food applications.
In parallel with the increase in the population in the world, the amount of milk production also increases and a significant part of it is processed into cheese. Whey, which is mostly a by-product of the cheese industry, has a very high nutritional value and is used in the production of different cheeses in various countries. Ricotta in Italy, Argentina and America, Mysost, Primost, Gjestost, Grubransdalsost in Norway, Schottenziegr, Hudelziger, Mascarpone in Switzerland, Requesón in Spain, Serac, Brousse, Broccio, Greuil, Zieger, Schottenzieger, Schabzi in France, Manouri in Greece, Myzithra, Anthotyros, Ziger in Romania, Urda, Klila in Tunisia, Urda in Israel, Requeijão do Norte in Brazil, Ricotta fresca could be examples of cheeses made from whey. In Turkey, cheese such as Lor Peyniri (widely), Tire Çamur Peyniri, Horç, Tort/Dolaz, Kopanisti, Armola, Sepet Loru, Kirli Hanım Peyniri, Taze Keş, Sarı Keş, Antakya Sürkü, Antakya Küflü Sürkü, Sirvatka Loru, Dumas Çökeleği, Otlu Lor and Şor Loru, are cheeses made from whey. Whey cheeses produced in Turkey have been dealt with separately or in summary in the literature and gathered in a joint report with this study.
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Expensive and time-consuming methods are currently used to identify manipulated whey protein concentrate (WPC). We tested the application of attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy to detect and quantify adulteration of WPC with wheat flour (WF). ATR-FTIR is based on the interaction between IR radiation and the molecular bonds in the samples, allowing the capture of its vibration energy and the acquisition of spectra with information that can be used to identify and quantify functional groups. WPC Samples were adulterated with different percentages of WF and spectra were collected. Amide I and II bands exhibit a decreasing protein content when more WF is added. Conversely, at the carbohydrate characteristic band (1080 cm⁻¹), there is an increasing intensity as more WF is added. Partial least squares (PLS) regression models presented low prediction errors and high coefficients of determination. Furthermore, one of the models was chosen for a blind prediction test of 10 samples adulterated with random amounts of WF, and it could make reasonable predictions of the actual levels of adulteration. Therefore, ATR-FTIR spectroscopy coupled with multivariate analysis shows strong potential to detect adulteration in WPC with WF and the capability to quantify the added mass content.
Background: Whey protein supplements might be a potential risk factor for the restoration surface due to its pH and lactose content. Aim: The study aimed to evaluate the effect of whey protein beverages on the microhardness of four restorative composites with different microstructures (Filtek Z 350XT, Filtek Z 250XT, Filtek Bulk Fill (FBF), and Filtek P 60). Materials and methodology: Forty disc-shaped samples from each material (in total 160) were prepared and wet polished. The samples of each group were randomly divided into four subgroups and subjected to four immersion media namely, whey protein Concentrate (WPC), whey protein Isolate (WPI), whey protein water (WPW), and distilled water (DW). The immersion protocol was performed twice for 10 min daily for 30 days followed by immersion in artificial saliva for another 10 min and stored in DW till the next cycle. The pre immersion and post immersion microhardness of all the samples were recorded with a Microhardness Tester FM-800. Data obtained were statistically analyzed using SPSS 25 software. Results and conclusions: All composites exhibited decline in microhardness, except for FBF. P 60 composites which showed the highest decline in microhardness. WPC and WPI caused the greatest reduction in microhardness compared to WPW.
The physicochemical and sensorial properties of whey protein isolate (WPI) wheat-based crackers were evaluated by varying WPI at the levels of 0, 5, 15 and 20% (w/w). Textural properties, water activity, protein, moisture content, dough rheology, sensorial properties, as well as colour, thickness and spread factor were assessed. Addition of WPI from 0 to 15% (w/w) decreased the viscoelasticity of cracker dough significantly due to the high water hydration ability of the WPI. As a consequence, it influenced overall cracker texture and spread ratio. However, increasing the WPI to 20% (w/w) improved dough viscoelasticity behaviour as the G’ and G” increased sharply. WPI-wheat based crackers were softer and addition of 20% (w/w) showed good overall acceptability. Therefore, addition of WPI could be a promising technique to improve the structure and quality of wheat-based crackers.
Oleanolic acid (OA), an important natural product, bears variety of pharmacological actions of interest; but its use in the modern therapy is limited due to low water solubility and dissolution rate. The main objective of this study was to develop the lyophilized oleanolic acid nanosuspension (OA-NS) using whole whey. The prepared OA-NS was evaluated by using FTIR, TLC, DLS, SEM, TEM, AFM, DSC, PXRD, dissolution and stability study. To determine the efficacy of OA-NS over free OA in terms of dissolution rate, the in vivo antidiarrheal study was carried out in male Wistar albino rats. The prepared OA-NS particles revealed its nearly spherical shape with mean particle size less than 100 nm. In compatibility study, no possible irreversible molecular interactions were found. The dissolution rate of OA in the form of OA-NS was found to be better as compared to free OA possibly due to transformation of crystalline state to amorphous also supported by in vivo antidiarrheal study. The results demonstrated that the whole whey stabilized OA-NS provides novel approach to increase the dissolution rate along with long term stability to OA which can also be potentially useful for the other poorly water soluble drugs.
An exponential growth in the global demand for high quality proteins over the next 20 years is expected, mainly due to global population growth and the increasing awareness toward protein rich foods for more nutritive diets. Coupled with this, is the pressing need for more sustainable approaches within a bio-economy mindset. Although meat production is expected to increase to address this rising demand, a better use of the currently available resources provided by the food, and specially, the meat industry is required. In this regard, despite the high-quality proteins and other nutrients found in meat co-products; they are currently underused and their valorisation needs to be revisited. Also, emerging protein sources need to be investigated to alleviate the environmental pressure coming from the meat industry. In this review, the main focus was attributed to (i) the current and forthcoming challenges for the use of meat co-products as meat replacers to produce a new range of meat derived products (with high nutritional value, improved technological properties and better consumer acceptance); (ii) their performance regarding to the non-animal origin proteins currently used as meat protein replacers; and (iii) the allergenicity of the proteins that might fall into the category of novel protein sources.
Whey Processing, Functionality and Health Benefits provides a review of the current state of the science related to novel processes, functionality, and health benefit implications and documents the biological role of whey protein in selected areas that include muscle metabolism after exercise, muscle and body composition in the elderly, weight management, food intake regulation, and maintenance of bone mass. The topics addressed and the subject experts represent the best science knowledge base in these areas. In some of these areas, the state of the art and science are compelling, and emerging data are confirming and solidifying the human knowledge base. Collating the understanding and knowledge of the metabolic roles of whey protein and developing the clinical datasets that demonstrate efficacy for improving human health will speed up new product innovations and sustainable opportunities for the food industry as evidenced by the processing and functionality research conducted so far. Topics covered in this volume include: Whey utilization history and progress in process technology. Fractionation and separation with health implications. Whey emulsions and stability in acidic environments. Current applications in films, coatings, and gels. Texturized whey in snacks, meat analogs and candies. Nanoparticles in hydrogels for delivery of bioactive components. Whey protein role in human health. Health and wellness, processing and functionality are clearly areas of continuing research and offer growth opportunity for the food industry. The benefits from such concentrated body of knowledge will be new ingredients and innovative products that improve overall wellbeing. Whey Processing, Functionality and Health Benefits provides food scientists and manufacturers insight into the health implications of whey protein science. Ultimately, the consumer will benefit from better formulated, healthier products.
Whey protein concentrate preparations, prepared by electrodialysis, ultrafiltration, reverse osmosis, gel filtration, and reagent complexation, are highly variable in their composition and functionality. The im- portant functional properties of whey protein concentrates are solubility, whip- ping and foaming, emulsification, and gelation. Factors affecting these properties include: whey source and composition, cheese or casein manufacturing conditions, heat treatment conditions, fractionation and isolation conditions, storage con- ditions, overall sanitation conditions, and techniques used for functionality evalua- tion. Process modifications such as selective heat treatment, selective de- mineralization or ion exchange, and preteolytic enzyme hydrolysis may be used to alter these functional properties for a desired use application.
Whey protein concentrate (65% protein) mixtures, alone or in the presence of NDM, were heated at 66 and 71°C for up to 120 min to yield 16, 25, and 35% TS to simulate the formulation of a nutritional product. Addition of low heat NDM to a whey protein concentrate mixture to yield 35% TS resulted in 6 and 20% denaturation after 120 min and 27 and 83% in the whey protein concentrate mixture (16% TS) at 66 and 71°C, respectively. The effects of Ca and pH on whey protein denaturation and aggregation (66°C) were also studied. A whey protein concentrate mixture (16% TS) dialyzed against simulated milk ultrafiltrate containing 0 to 9 mM Ca and heated (66°C); the mixture was progressively more denatured and formed less soluble aggregate and more insoluble precipitate as the Ca increased. When the whey protein concentrate mixture (16% TS) was heated (66°C) at increasing pH (5.8 to 7.0), whey protein denaturation and insoluble precipitate increased. The α-LA denatured more extensively than β-LG at 66 and 71°C.
beta-Lactoglobulin (beta Lg) was subjected to limited hydrolysis by trypsin, plasmin, and endoproteinase from Staphylococcus aureus V8 (S.aur.V8) to degrees of hydrolysis (DH) of 1, 2, and 4%. The several hydrolysates had different peptide compositions (determined by reversed-phase HPLC and gel-permeation chromatography [GPC]). GPC under nondenaturing, denaturing, and denaturing plus reducing conditions showed that the peptides formed were linked by hydrophobic interactions or by disulfide bonds or were not linked at all. At very low protein concentration, some differences in emulsion-forming properties were observed: only the plasmin hydrolysates could form emulsions with a uniform particle-size distribution. The emulsions formed with S.aur.V8 hydrolysates had poor emulsion-stabilizing properties. Some hydrolysates showed increased foam-forming properties in comparison with the intact protein. All foams formed were stable. Overall, the plasmin hydrolysate (DH4) contained relatively much larger molecules and/or hydrophobic molecules. Many molecules were disulfide-linked peptides. This hydrolysate also had the best functional properties.
Whey protein ingredients are used for a variety of functional applications in the food industry. Each application requires one or several functional properties such as gelation, thermal stability, foam formation or emulsification. Whey protein ingredients can be designed for enhanced functional properties by altering the protein and non-protein composition, and/or modifying the proteins. Modifications of whey proteins based on enzymatic hydrolysis or heat-induced polymerization have a broad potential for designing functionality for specific applications. The effects of these modifications are demonstrated by discussing how they alter gelation and interfacial properties.
Although several studies have shown that milk protein components have a wide range of biological activities, the potential role of these proteins in the gastrointestinal mucosal defense system is less well elucidated. In this study, we investigated the effect of the major proteins in cow's milk on gastric mucosal injury by using two acute ulcer models in Wistar rats. Gastric mucosal injury was induced by either intragastric 60% ethanol-HCI or water-immersion restraint stress (23°C, 7 h). Each test milk protein was orally administered 30 min before the induction of gastric injury. Among the major milk proteins, α-lactalbumin (α-LA) is demonstrated to have a marked protective effect against ethanol-induced gastric injury, with the same potency as that of the typical antiulcer agent, Selbex. Whey protein isolate (WPI), which contained 25% α-LA, also protected against gastric injury, while casein showed no effect. Comparative studies on the protective effect of the four major components of WPI, β-lactoglobulin, α-LA, bovine serum albumin and γ-globulins (immunoglobulins), on the basis of their contents in WPI revealed that α-LA was responsible for the protective effect of WPI, being about 4-fold more effective than WPI itself. α-LA showed dose-dependent protection against gastric injury induced by stress as well as ethanol. Pretreatment with indomethacin (10 mg/kg body weight, s.c.), which is a potent inhibitor of endogenous prostaglandin synthesis, resulted in a significant reduction in the protective effect of α-LA. These results indicate that α-LA has marked antiulcer activity as an active component of cow's milk protein, and suggest that α-LA intake may serve to protect against gastric mucosal injury, in part through endogenous prostaglandin synthesis.
Whey protein concentrate (WPC) solutions containing 10, 30, 60 and 120 g dry powder/kg were heated at 75°C and whey protein aggregation was studied by following the changes in the distribution of -lactalbumin and bovine serum albumin, using one dimensional and two dimensional PAGE. The one dimensional PAGE results showed that a minimal quantity of large aggregates was formed when 10 g WPC/kg solutions were heated at 75°C for up to 16 min whereas appreciable quantities were formed when 30, 60 and 120 g WPC/kg solutions were similarly treated. The two dimensional PAGE analysis showed that some disulphide-linked -lactoglobulin, -lactoglobulin in each sample were greater than the quantities of native-like protein. However, in WPC solutions of 10, 30 and 60 g/kg, the differences between the amounts of native-like and SDS-monomeric proteins were slight. The loss of the native-like or SDS-monomeric proteins was consistent with a first or second order reaction. In each case, the apparent reaction rate constant appeared to be concentration-dependent, suggesting a change of aggregation mechanism in the more concentrated solutions. Overall, these results indicate that in addition to disulphide-linked aggregates, hydrophobic aggregates involving -lactalbumin and bovine serum albumin were formed in heated WPC solution at high protein concentration, as suggested by model studies using binary mixtures of these proteins.
The changes in protein aggregation and storage modulus of mixtures of β-lactoglobulin and α-lactalbumin were measured, by gel electrophoresis and dynamic rheology, respectively, during 60 min of heating at 75 or 80 °C in a buffer simulating the whey protein concentrate environment. The results were consistent with the formation of heat-induced hydrophobically bonded aggregates involving both α-lactalbumin and β-lactoglobulin that undergo disulfide bond interchange reactions within the aggregate as the basis for the generation of gel strands and gels. The apparent difference in response to heat treatment at 75 °C between mixtures of bovine serum albumin (BSA) and β-lactoglobulin and mixtures of α-lactalbumin and β-lactoglobulin is likely to be based on at least three factors:  the different thermal transition temperatures of the three proteins; the possibility of self-initiation of thiol−disulfide interchange reactions for BSA and β-lactoglobulin, but not α-lactalbumin; and the ability of α-lactalbumin to form interprotein aggregates with each of the other two proteins prior to disulfide bond interchange and gelation. Keywords: Whey protein concentrate; hydrophobic aggregation; disulfide bonding