Thursday, August 9, 2007

Whey Protein Concentrates And Their Functional Properties


Whey Protein Concentrates (WPC) are nil but pulverizations made by drying the retentates from ultrafiltration (UF) of whey. They are described in footing of their protein concentration, protein content as per centum of dry matter, which runs from 25 to 80%. To obtain a 35% protein-containing product, the liquid milk whey have to be concentrated to about 5 fold, which have a sum solid of 8%. Concentration by ultrafiltration to a degree of 25 – 30 fold up is required to obtain 80% protein in the WPC with a sum solids content of 25%.

What are functional properties?

The functional places are defined as those properties, which find the overall behavior of proteins in nutrients during production, processing, storage and consumption. Whey proteins have got two types of places viz. nutritionary and functional. As for as nutritionary properties are concerned, the milk whey protein concentrates are rich in indispensable aminic acids such as as lysine, tryptophan, cystine, and methionine enabling its usage in baby nutrient and aged people diet as well as in enrichment of cereals. Whey proteins are known for their high solubility over a broad scope of pH, (lower the pH, higher the solubility), better aeration properties, ability to constitute colloidal gels at high temperature, and better H2O and fat binding properties.

The of import functional places of the milk milk whey protein concentrates can be listed as follows.

Water solubility

The solubility of whey protein is considered as the most of import 1 because it impacts the other functional places like gelling, foaming, and emulsifying properties. When the temperature increases, the solubility of milk whey protein is lost since they are heat energy sensitive. Among them, the Igs are more than sensitive as they are denatured at a temperature of 70°C followed by alpha lactalbumin, beta lactoglobulin and blood serum albumen defies temperatures up to 100°C.

The proteose-peptone constituent is the most heat energy resistant among the full milk whey protein component. Denaturation by heat energy is nil but breakage of sulfur span within the molecule resulting in unfolding and insolubility. The insolubility attains its upper limit at a pH scale of 4 but even at this level, the solubility is around 60%.

Water absorbing capacity

The upper limit H2O soaking up by the milk whey protein dressed ore happens when the exposure is between 5-10 min. But Na caseinate and soybean protein insulates are capable of absorbing H2O better than the milk whey protein concentrates. Water soaking up is least affected by alteration in pH, salt concentration but warming generally favors especially when the temperature is around 80°C. This place can be utilized in baking industry.

Gel forming ability

Unfolding of protein iron coupled with exposure of aminic acids consequence in colloidal gel formation. This is owed to the formation of H Ionic bonds. When protein iron are linked by the H bonds, pits are formed in them absorbing H2O and the construction formed is a web of three dimension encircling pockets of water. Heating causes the unfolding and higher the temperature, the colloidal gel formed is stronger. If 80% concentrated WPC is heated, colloidal gel formation can be noticed on cooling.

Foaming ability

Foaming is nil but the incorporation of air to constitute a stable structure. Formation of froth depends on partial unfolding of protein iron at the air-liquid interface. Denatured milk milk whey proteins have got got mediocre snappy places and to have a better snappy property, terrible heat energy treatment of whey proteins should be avoided. But mild heat energy treatment be givens to favor or better the snappy ability of the milk whey proteins.

Foaming ability can be measured by snappy time, over tally and froth stability. The peak over tally is obtained when the milk whey protein is at its peak solubility in which there will be mild but not zero denaturation. The milk milk whey protein dressed ore is a better replacement for egg white, the usage of which in nutrient is objected to by hard-and-fast vegetarians.

Emulsifying ability

The surface places of the whey proteins do them good emulsifying agents. The surface places also regulate the foaming and snappy qualities owed to decrease in the interfacial latent hostility between the hydrophilic and hydrophobic constituents in the food. This place is common in nutrients rich in fat and water. Emulsifying capacity may be defined as the amount of oil, which can be emulsified, by certain measure of protein prior to phase inversion or collapse of the emulsion.

Emulsion stableness is defined as the ability of the protein to constitute an emulsion, which stays unchanged over a given time period and conditions. The emulsifying ability or capacity directly depends on the solubility of the milk whey protein. Hence the factors that affect the solubility in bend modulate the emulsion formation.

Nutritional value

The nutritionary value of the milk milk whey protein dressed ore is definitely higher when compared to other word forms of protein.


Nature of protein

Biological value


Whey protein



Whole egg protein



Milk protein



Beef protein






Potato protein



Wheat protein


It can be inferred from the above tabular array that the biological value of casein is less than the whey protein because it is deficient in many indispensable aminic acids.

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