Whey protein

From Wikipedia, the free encyclopedia

This bodybuilding supplement contains whey protein and creatine monohydrate, as well as vitamins and other supplements.

This article includes a list of references or external links, but its sources remain unclear because it lacks inline citations. Please improve this article by introducing more precise citations where appropriate. (April 2009)

Whey protein is the collection of globular proteins that can be isolated from whey, a by-product of cheese manufactured from cow's milk. It is typically a mixture of beta-lactoglobulin (~65%), alpha-lactalbumin (~25%), and serum albumin (~8%), which are soluble in their native forms, independent of pH. Whey has the highest biological value (BV) of any known protein.

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 beta-lactoglobulin, alpha-lactalbumin, bovine serum albumin and immunoglobulins. Each of these components has important disease-fighting effects.^{[citation needed]} In addition, whey protein is easily digestible.

[edit] Denaturation by heat

Whey protein can be denatured by heat. High heat (like the sustained high temperatures above 72 degrees Celsius (160 degrees Fahrenheit) associated with the pasteurization process) denatures whey proteins, destroying some bioactive compounds, such as the amino acid cystine. While native whey protein does not aggregate upon renneting or acidification of milk, denaturing the whey protein triggers hydrophobic interactions with other proteins, and the formation of disulfide bonds between whey proteins and casein micelles, leading to aggregation with other milk proteins at low pH.

[edit] Major forms

Whey protein typically comes in three major forms: concentrate, isolate, and hydrolysate.

• 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 — they are 29%-89% protein by weight.
• Isolates are processed to remove the fat, and lactose, but are usually lower in bioactive compounds as well — they are 90%+ protein by weight. Both of these types are mild to slightly milky in taste.
• Hydrolysates are predigested, partially hydrolyzed whey proteins that, as a consequence, are more easily absorbed, but their cost is generally higher. Whey protein hydrolysate also tends to taste quite different than other forms of whey protein, usually in a way that many find undesirable but can be masked when used in beverages.^{[citation needed]}

[edit] Uses

Whey protein is a common bodybuilding supplement

More than other protein supplements, whey protein powder is commonly used by bodybuilders and other athletes to accelerate muscle development and aid in recovery. Some individuals with suppressed or otherwise abnormal immune systems or degenerative diseases use undenatured bioactive whey proteins to increase their antioxidant levels. These native whey proteins are a good source of cysteine, a conditionally essential amino acid, which is the rate-limiting factor for the body's production of glutathione^[1], an important antioxidant.

Whey protein has also seen increased use among people trying to maintain or lose weight. Whey protein is a high quality, low fat protein and is used successfully in many diet programs. Recent studies have shown that high protein meals decrease ghrelin concentrations in the body and therefore satiate hunger. ^[2]

In a study, it was found that whey supplements may prevent blood sugar spikes after high-carbohydrate meals, which is useful for diabetics.^[3]

[edit] See also

• Bodybuilding
• Bodybuilding supplement

[edit] References

[edit] External links

• Whey Protein research and science information at wheyprotein.com
• Whey Protein: Waste Product of the Past Nutritional Powerhouse of the Future
• Whey Protein Profile at SupplementData.com
• Whey Proteins at Nutriline.org