What are
Whey protein is the English name for "whey protein", a powdered protein mix obtained from the liquid - called buttermilk, whey or whey - obtained from the processing of cheese.
Whey is particularly rich in proteins of the same name, which represent the most precious protein fraction of this food. Their biological value is in fact extremely high, as are the other protein quality indices.
A few lines ago we talked about protein mix because whey proteins are made up of various types of proteins, in particular beta-lactoglobulins (~ 65%), alpha-lactalbumin (~ 25%), serum albumins (~ 8%) and immunoglobulins .
What are they for
Whey proteins find a wide range of applications, ranging from the food industry (they are a common additive, especially in confectionery foods, such as pastries, creams, puddings and baked goods) to the zootechnical one. However, it is in the food supplement sector that whey proteins find their best known application. Compared to other protein sources (eggs, soy, wheat, casein, etc.), in fact, Whey boast some peculiar characteristics:
- high content in branched chain amino acids;
- superior biological value due to the excellent presence of essential amino acids;
- high digestibility with rapid increase in postprandial plasma amino acid concentration.
Thanks to these characteristics, Whey proteins:
- provide the substrates necessary for protein synthesis (in which some B vitamins commonly added to whey protein supplements participate);
- suppress protein catabolism;
- promote recovery after strenuous training;
- act as a substrate for gluconeogenesis (production of energy starting from some amino acids, which becomes important in prolonged fasting and physical activity of duration);
- stimulate protein synthesis and promote muscle growth; they increase insulin release, decreasing postprandial blood glucose.
Isolate e Concentrate
In the varied market of food supplements, different types of whey proteins can be found. In general, a product is considered of higher quality the higher the protein content and the lower the percentage of carbohydrates (lactose) and fats. These characteristics also affect the price of the product, as the cost of the isolated raw material is higher. With the addition:
- vitamins (they are important but cheap)
- creatine (the Chinese one has a particularly low cost and increases protein nitrogen, allowing you to use less protein in the product)
- carbohydrates (maltodextrins cost much less than whey proteins)
they do not justify a higher price than whey protein-only supplements.
Regarding the raw material used, beyond the different sources of origin, Whey supplements may contain isolated or concentrated whey proteins. The latter are richer in fats, lactose and minerals, compared to a lower protein content (70-85%). For this reason they are less expensive than isolated whey proteins, where the protein content is on average between 89 and 94%. In the presence of lactose intolerance, therefore, isolated whey proteins are undoubtedly a better choice, even if slightly more expensive. If, on the other hand, the goal is simply to build muscle mass, even concentrated proteins are a good compromise between quality and price.
Lo ion exchange is the technique that allows to obtain isolated Whey proteins with the highest protein concentration (> 90%), but poor in some important components - such as lactoferrins, immunoglobulins and glycomacropeptides - which are lost or denatured during the production phases (the exchange process ion separates proteins on the basis of their electrical charge, through the use of certain chemicals). These fractions are instead conserved with the various filtration methods used to produce concentrated Whey protein; among these the classic microfiltration techniques and ultrafiltrazione, which use physical filters to separate fat and lactose from the protein, without damaging it (the differences between the two are minimal and depend on the size of the filtration pores, about a micrometer large in microfiltration and 4 times smaller in ultrafiltration). As mentioned above, ultrafiltered and microfiltered Whey proteins tend to have a lower protein content (about 80%) than ion exchange ones (which reach or slightly exceed 90%). The best compromise, in this sense, is offered by Whey proteins obtained using a technique called cross-flow microfiltration, which allows to reach protein levels close to 90% while preserving important components such as lactoferrins and macropeptides.
