Whey is one of two major sources of protein found in milk and makes up around 20% of the protein in Cow's milk, by weight (the other is casein, which makes up 80%.). Up until the mid 1970's, the whey constituent of milk was considered a waste product from the manufacture of cheese, and was simply discarded. It wasn't until modern filtration processes became available in the 1980's that the full nutritional value of whey protein became apparent. Whey protein is comprised of four major and six minor protein fractions. The major protein fractions in whey are beta-lactoglobulin, alpha-lactalbumin, serum albumin and immunoglobulins. Along with the minor fractions, each of these fractional components that make up whey have been shown to have extraordinary effects on preventative health, health maintenance and recovery. From health issues as diverse as gut integrity and motility, immune function and support, cancer, cardiovascular health and performance enhancement; whey protein's spectrum of established benefits is unrivaled.
The two most common whey protein supplements are whey protein concentrate (WPC) and whey protein isolate (WPI). WPC is produced by a process known as ultrafiltration, a low temperature process that uses pressure and a porous membrane to separate the fat and lactose from untreated sweet whey. This produces a product with approximately 78-83% protein, 6-8 % fat and 4-6% lactose. To produce WPI, WPC is further processed using either cross-flow microfiltration (CFM) or microflitration (MF), both of which further separate whey protein from fat and lactose using high-tech ceramic filters. This produces a WPI comprised of approximately 90% protein,
Whilst WPI is marketed as a superior product to WPC, in most respects it is actually inferior due to its significantly lower levels (WPC contains up to 800% more) of a group of bioactive compounds known as 'growth factors' (IGF-1, IGF-2, TGF-B, PDGF and FGF). These growth factors are contained within the fat globule membrane of whey, but the further filtration required to produce WPI, also removes these beneficial fat globules in order achieve a fat content of less than 1%. Oral absorption of growth factors has been well documented and they have been shown to help improve wound healing as well as various afflictions of the gastrointestinal tract. They are also thought to exhert an anabolic effect if whey consumption is high enough.
Whey also has a superb amino acid profile. It is extremely rich in essential amino acids (50%), branched-chain amino acids (25%) and leucine (10%) and scores highly on all methods used to score protein quality. Whey is also fast-digesting for a native protein, which means it is emptied from the stomach quickly, resulting in a pronounced and rapid increase in plasma amino acids.
The rate of absorption of dietary proteins largely determine their effects on protein synthesis and protein breakdown. Consuming a 40 gm serving of whey protein elicits a rapid rise in plasma amino acids (hyper aminoacidemia), with a correspondingly high and rapid rise in levels of protein synthesis (by 68% with peak levels occuring 40-140 mins post consumption). The resultant net nitrogen gains from using this protocol, peak at about 2 hours and are maintained up to about 3 hours post ingestion. However, protein oxidation is also increased and there is minimal effect on protein breakdown. Curiously, by altering the rate of ingestion it is possible to totally change the metabolic response from anabolic to anti-catabolic. Simply consuming the same 40 gms serving, gradually and evenly over 3 hours can halt protein breakdown on a par with slower proteins such as casein, further increasing the versatility of this remarkable protein source.
So as you can see - Whey Protein Isolate does not appear to the the "best" form of protein when you take into account what is actually being removed to give it a higher protein content / %
This articles was compiled with the help of Bulk Supplements Direct - Bulk Sports Supplements @ Bulk Prices
Whey is one of two major sources of protein found in milk and makes up around 20% of the protein in Cow" - Bulk Sports Supplements @ Bulk Prices - Whey Proteins, Bodybuilding Supplements, Nutritional Supplements and lots more!