Whey, also known as lactoserum, is the main waste product in cheese production and is obtained from the separation of rennet from milk. Whey contains 50% of nutrients, as it is rich in carbohydrates, proteins, lipids, vitamins, minerals, and water.

Adding value to whey has been of interest not only to the food industry but also to the research area. The latter is because whey proteins are multifunctional since their concentrates produced after filtration can be applied in the food area in various industrial processes, due to their foam, gel, and emulsion forming properties. Among the products found in the market are dairy products (e.g. yogurt, cheese), sauces, noodles, cookies, meats, among others.

Whey proteins have a high biological value since they contain essential amino acids, which makes them attractive for use in the preparation of various fruit-based drinks, carbonated drinks, and, the best known, sports drinks; in general, the latter contain carbohydrates, minerals, flavorings, and colorings, since their main function is to prevent dehydration and recover the loss of carbohydrates and electrolytes. In addition, some beverages may contain small amounts of protein (approximately 5%), mainly from whey.

Previous studies have shown that these proteins delay fatigue and counteract muscle protein breakdown. In this last aspect, whey proteins are rich in amino acids such as leucine, isoleucine, and valine, which are indispensable for stimulating the production of proteins in the muscle, that is, for recovering and regenerating the tissue. For this reason, we are increasingly finding on the market sports drinks containing whey proteins.

On the other hand, whey protein hydrolysates are used as supplements for people with special needs, such as the elderly and premature babies, among others. These hydrolyzed proteins contain essential amino acids, so they are rapidly absorbed by the digestive tract, compared to other types of non-hydrolyzed proteins. In addition, these whey protein hydrolysates have been associated with a lower risk of developing allergenicity.

Whey proteins are better absorbed than other types of proteins, which is why their consumption has been recommended for different types of athletes. In this sense, it has been shown that, for bodybuilders and people seeking to increase muscles, it is advisable to include whey protein in their diet with foods that provide macronutrients, together with resistance exercise. The consumption of whey protein is also recommended to improve body composition.

Research findings have suggested that, when consumed before exercise, it promotes the body's use of fat as an energy source by maintaining muscle tissue. However, long-term consumption of high-protein diets can cause kidney damage, so individuals must seek the care of a nutritionist.

In addition to the benefits found for muscle reconstruction in athletes, several studies have shown that fragments of whey proteins are beneficial to health. In this regard, antioxidant, antihypertensive, immunomodulatory, and antidiabetic effects, among others, have been widely reported in several countries. Therefore, the industry and the scientific community are looking for new alternatives to give added value to whey proteins.

Source: Lilia M. Beltrán-Barrientos, Belinda Vallejo-Córdoba and Aarón F. González-Córdova, researchers of the Chemistry and Biotechnology of Dairy Products Laboratory of CIAD.