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04-01-2007, 04:01 PM
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Whey Basics
Whey Basics
Lets start out with the two major types of Whey Protein - Whey Protein Concentrate (WPC), and Whey Protein Isolate (WPI). Whey protein is a by-product of cheese and casein production. Pure whey contains a large amount of the milk sugar lactose, as well as a variety of proteins, fat and cholesterol. To remove the undesirable components and produce a more pure protein, different filtration techniques can be employed. The most common are ultrafiltration and microfiltration, all of which are low temperature methods and so avoid denaturing the protein. Denaturing of protein, which occurs through the use of cheaper extraction methods using high temperatures and acid treatment, destroys the important protein fractions, lowering the biological activity or effectiveness of the protein. Denaturing can also occur after manufacture due to high temperatures. Never expose whey protein to high temperatures and direct sunlight for extended periods. Avoid leaving protein in a hot car, next to the oven in the kitchen or any other source of heat. Also avoid using whey protein in recipes that use high heat - muffins, pancakes etc, as this will denature the protein as well. WPC and WPI High quality WPC's are typically 70-90% protein, and are reasonably low in fat and lactose. WPI's however are typically greater than 85% protein, with some being upwards of 95% protein. The most common extraction methods used to produce WPI's are Ion-exchange (IE), Cross flow Microfiltration (CFM) and Ultrafiltration (UF). Because of the extra cost involved in the production of CFM and ultrafiltered whey isolate the majority of supplement companies use ion-exchange whey. The Ion-exchanged (IE) process produces the most pure protein, gram for gram (around 95% protein), when compared to microfiltration and removes the protein through an ion-exchange column. This takes advantage of the specific electronic charges of the protein, fat and lactose contained in the whey and uses opposite charges to extract each individual component. Unfortunately this process uses chemical reagents to control the electrical charges. This can change the pH level and denature the whey by destroying some of the biologically active protein fractions. Crossflow Microfiltered (CFM) Whey Isolate is produced by passing the whey protein concentrate through natural, nonchemical ceramic membranes to remove the fat and denatured protein and is typically around 91% protein. Since chemicals aren't used in this process, very little of the protein is denatured so the protein retains the important protein fractions. Protein fractions Protein fractions are the active components of whey that have their own unique effects on health and can help enhance immune function and improve recovery from training. These include: Beta-Lactoglobulin - This is present in the greatest amounts but unfortunately is considered an allergenic fraction in whey. Good whey proteins should be less than 50% Beta-lactoglobulin, however, the ion exchange process isolates this particular fraction easily and so Ionised WPI's will be quite high in this. To avoid any allergies from this, avoid whey proteins with higher than 70-80% of Beta-lactoglobulin. The higher the percentage of Beta-Lactoglobulin, the lower the percentages of the higher biological value fractions. Alpha-Lactalbumin - This nutritious fraction is found in the second highest levels at around 15-20% and can also be found in mother's milk. Immunoglobulins (IgG) - This fraction helps to stimulate the immune system with IgG's having important antibody activity within the body, helping support the immune system and preventing disease. Bovine Serum Albumin (BSA) - This fraction is a precursor to glutathione. Glutathione is an essential water-soluble antioxidant in the body that protects cells and serves as a primary detoxifier of harmful compounds such as peroxides, heavy metals, carcinogens and many more. Betalactoglobulin and IgG fractions are also important sources of glutathione. Glycomacropeptides (GMP) - GMP is a powerful stimulator of cholecystokinin, which plays many essential roles relating to gastrointestinal function, including the regulation of food intake. In addition to being a regulator of food intake, cholecystokinin (CCK) stimulates gall bladder contraction and bowel motility, regulates gastric emptying, and stimulates the release of enzymes from the pancreas. The pancreatic enzymes are critical for the complete digestion of fats, proteins and carbohydrates and therefore the full nutritional realization of food. Also, CCK has the effect of slowing the overall digestive process by slowing intestinal contractions, thus giving the digestive enzymes more time to work on their respective substrates resulting in more complete absorption. In animals, a rise in cholecystokinin is followed by a large reduction in food intake, as by slowing digestion, one perceives the "full" feeling longer following a meal. Lactoferrin (LF) - This is quite an important fraction for its immune enhancing effects. Lactoferrin (LF) is found in tiny amounts in the body, yet appears to be a first-line immune-system defence. LF is a powerful antioxidant and strongly inhibits iron-dependant free radical reactions by directly binding iron. This iron binding effect results in the inhibition of iron dependant bacteria growth, and can block the growth of many pathogenic bacteria and yeast. Its antimicrobial action may also improve antibiotics. In the digestive tract, LF may help by stimulating intestinal cell growth and enhancing the growth of "good" intestinal microflora. Lactoperoxidase, Lysozyme, Growth Factors - These are very minor fractions yet are reported to be the most biologically active. Lactoperoxidase (LP) has a high antimicrobial activity, and inactivates or kills a wide spectrum of microorganisms. Lysozyme, present in only very small amounts in cow's milk, possesses antibacterial activity against a number of bacteria and works synergistically with lactoferrin against bacteria such as the Salmonella species. Lysozyme is found in saliva, tears, and other body fluids, where it acts as a natural antibiotic. Growth Factors include IGF-1 and IGF-2. IGF-1, or Insulin-like Growth Factor, is the hormone released during growth hormone metabolism, the amount produced which determines the extent of growth in children and the building of muscle and lean body mass in adults. Studies have shown that IGF-1 rises in direct proportion to the quality and quantity of protein in the diet. Hydrolysing (predigesting) whey to make di-, tri-, and oligo-peptides (short and long chain amino acids), increases the bioavailability (BV) of the whey, further increasing the release of IGF-1. As you can see, the greatest differences between the two types of WPI lies in the immunological and digestive implications of the proteins, with IE WPI missing three significant protein fractions, Lactoferrin (LF), lactoperoxidase (LP) and Glycomacropeptides (GMP). Hydrolysates and Peptides Hydrolysates are essentially smaller proteins. These are produced by subjecting proteins to digestive enzymes, which breakdown the large protein molecule into many smaller proteins. These proteins can be broken down into peptides (chains of two amino's) or polypeptides (chains of three or more aminos), and are broken down until they are the right size for absorption. This process occurs naturally during digestion but can take some time, up to several hours for whole foods. So it is possible to buy whey proteins with added peptides or "predigested" hydrolysates. Predigested hydrolysates are when the proteins are exposed to natural enzymes from plant or animal sources. Protein hydrolysates are of benefit as they more easily and more quickly absorbed. These can be most beneficial after training when there is an increased need for amino acids. The aminos are required to prevent protein (muscle tissue) breakdown, so the faster they can be absorbed the better. Another factor effecting absorption rates is the molecular weight of the formula. The lower the molecular weight of the protein the faster the absorption. Whey proteins with added whey peptides will often state the weight in Daltons (D) of the protein: i.e. MW 500D (very low molecular weight), MW 80,000D (high molecular weight). What to choose? Choosing which protein to use depends on what you are looking for. Using Whey Isolates, Hydrolysed proteins and Whey proteins with added peptides will offer increased recovery when used straight after training due to their quick absorption. However during the course of the day when absorption rates aren't quite as important, the use of the more basic proteins such as whey concentrate, casein and whole food protein sources may be more economical. Many of the whey proteins available today use a blend of two or more different wheys with some having added amino peptides. These are of benefit as they offer rapid absorption yet are more economical than some of the more pure whey protein isolates. If a product lists Whey Protein Isolate but doesn't differentiate between Ion Exchange or Microfiltered/Ultrafiltered it is possible to guess what type it is by the mineral composition. The Ion-exchange process results in a high sodium level - approx 470mg/100g, low potassium - approx 80mg/100g, and low calcium - approx 80mg/100g. In contrast, Microfiltered and Ultrafiltered results in a lower sodium level - approx 220mg/100g, higher potassium - approx 590mg/100g, and higher calcium - approx 490mg/100g. Thanks to Flex @ NZBB for this one. 
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04-01-2007, 04:02 PM
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Here's a very brief explanation for people wanting to know the difference between WPI & WPC & can't be bothered with all the other jargon....
Whey Protein Isolate and Whey Protein Concentrate So What's The Big Difference Between Whey Protein Isolate and Concentrate? Most of the whey protein powders you find will contain mostly whey protein concentrate with some whey protein isolate mixed in. You'll also find a lot of pure whey protein concentrate, and some whey protein isolate. Comparing the two, whey protein isolate is more expensive than concentrate - because it's of higher quality (more pure), and have a higher biological value (BV). Whey protein isolate contains more protein with less fat and lactose per serving. Usually, isolate contains 90-98% protein while whey concentrate contains 70-85%.* Whey protein isolate is the highest yield of protein currently available, and it comes from milk. Because of its chemical properties, whey protein is the easiest to absorb into your muscles. Obviously, with its high concentration, whey protein isolate 'would' be the best to use, but like all great things, there's always a downside. It's more expensive, and just because it's more pure, doesn't mean it'll give you more muscle and size. Its extra concentration may not justify the extra costs for you. Reference.
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04-02-2007, 09:22 AM
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