In terms of muscle recovery, whey protein is regarded as the most effective source of protein for the immediate repair of lean muscle mass. This is mainly due to the fact it has an amino acid profile which mirrors that of skeletal muscle, but also due to its ability to digest rapidly and get absorbed quickly from the intestines into the muscle. It is usually advised by many sports nutrition practitioners to consume around 20-30g of high quality protein following an intense bout of exercise in order to optimise the myofibril protein synthesis (MPS) response (the building of new proteins). This will provide a high level of the branch chain amino acids (BCAA’s), particularly Leucine as this is the main signalling protein which ‘triggers’ MPS.
Cow’s milk typically contains 3.5% protein, as well as 4% fat, about 4.6% lactose, 0.7% minerals, and 87% water. Of the protein fraction, whey contributes to just 20% and casein makes up the remaining 80% of the protein. The curds (casein) may be matured into various varieties of cheese and the liquid whey was commonly a waste product to be thrown away – drinking this would have been almost unbearable for anyone. Today this is the raw material for purified whey that many athletes and recreational gym-goers use to increase daily protein intake and help with the growth and recovery of lean muscle mass. However, the raw liquid whey is far from the purified powders found on the market today.
When raw whey comes out as a liquid it only consists of about 1% protein, 5% lactose, 0.6% minerals, 0.2% fat and the remaining 93% is water. To end up with highly purified whey, the raw material must be processed (usually through cross-flow microfiltration) to remove the fat, minerals, lactose and water in order to provide a finished powder which is highly concentrated in protein without have the bioavailability destroyed.
Furthermore, the process of separating the whey protein from the other constituents in the liquid whey results in the formation of a more concentrated product. Depending on the processes undertaken, the separated whey protein becomes either a whey protein concentrate (WPC), a whey protein isolate (WPI), or a whey protein hydrolysate (WPH). During the processing, fat and lactose are filtered out to make a lower fat, lower carbohydrate and higher protein powder. The final protein content in a whey product can range from 30% to 95% depending on the filtering process used. The higher the protein content, on a gram per gram basis, the more processing and filtering is needed.
Whey Protein Concentrate (WPC)
Whey Protein Concentrate usually contains between 75-85% protein, around 1-2% fat and 5-10% lactose. This is usually filtered using a unique process of microfiltration which, as the name suggests, involves the filtering through a membrane with microscopic holes. This is the lowest price of whey protein available on the market but the most popular amongst recreational gym-goers.
Whey Protein Isolate (WPI)
Whey Protein Isolate often uses an ultrafiltration process which removes more of the lactose and fat components from the protein providing a higher protein content per serving (>90%) and less fat and sugar than WPC. For this reason the price of WPI is slightly greater than WPC products.
Whey Protein Hydrolysate (WPH)
Whey Protein Hydrolysate is usually a WPI that has had some of its protein constituents broken down by enzymes into smaller peptides and amino acids. This process is usually carried out in out intestines by a gut enzyme and for this reason the speed of absorption is increased. Again, the price is usually higher than both WPC and WPI due to the more meticulous manufacturing process.
Take home message…
When looking for a whey protein supplement it is advised to carefully assess valuation against training goals and various other factors such as allergies, timing of intake etc. For example, if you are someone with a lactose intolerance then WPI would probably be a better choice due to the low lactose content. On the other hand if you have no allergies but still want a high protein content then WPC would be an ideal choice. WPH is more of a premium source of whey and does hold a fairly bitter taste due to its effectiveness. This would probably be more ideal for individuals who are looking for the greatest differences in their training where there are small margins for error, such as elite athletes. Finally, some products will have blends of different types of whey. This is usually to deliver high amounts of the key nutrients in whey. An example of this on the Myprotein range is Impact Whey Deluxe.