The Whey to Better Health

By Marie Spano, M.S., R.D., Contributing Editor

The nutrition benefits of whey protein make it an ideal ingredient for functional food and beverage formulations. Whey stimulates muscle protein synthesis and facilitates muscle-tissue repair after exercise. In addition, whey is satiating and can therefore assist with weight management. However, whey isnt just one protein, but instead describes various types of proteins that differ in composition and, therefore, food applications.

Composition differences

There are three main types of whey protein, whey protein isolate, whey protein concentrate and whey protein hydrolysates. Whey protein isolate contains 90% or more protein, very little fat and a minuscule amount of lactose. Whey protein concentrates vary in protein (29% to 89%, but typically from 34% to 80%), fat and lactose content; whey protein concentrates with a greater percentage of protein typically have less fat and lactose.

Whey protein hydrolysates are produced from purified protein heated with acid or broken down by enzymatic reactions into shorter chains for easier digestion and decreased allergenicity. Due to the different methods of production and degree of hydrolysis, the composition of whey hydrolysate ingredients vary based on their mixture of peptides and free amino acids. Hydrolysates are not only different from isolates and concentrates in composition, nutritionally they also produce a greater spike in insulin after ingestion in comparison to intact proteins (British Journal of Sports Medicine, 2006; 40: 900-905).

Whey proteins are made up of a number of individual protein components: beta-lactoglobulin (50% to 55% of the whey protein), glycomacropeptide (GMP), alpha-lactalbumin, lactoferrin, immunoglobulins, lactoperoxidase, bovine serum albumin (BSA) and lysozyme. These individual proteins can be commercially isolated and purified.

Research in brief

Whey protein is a natural, high-quality dairy protein derived from milk, and a complete protein that contains all the amino acids the body requires for muscle protein synthesis," according to Matthew Pikosky, Ph.D., R.D., FACN, vice-president, scientific affairs, Dairy Research Institute, Rosemont, IL. It also has a high biological value, which means that the protein is easily absorbed and used by the body." Whey proteins have a protein digestibility-corrected amino acid score (PDCAAS) of 1.14 and a biological value (BV) of 100.

In addition to containing all of the essential amino acids, whey is rich in branched-chain amino acids (BCAA) and the BCAA leucine, one of the key amino acids for blunting muscle catabolism while, according to research in animals, sparking muscle protein synthesis (Nutrition & Metabolism, 2010; 7:51). Studies consistently show that supplementation with whey protein can attenuate a decline in strength after a bout of muscle-damaging eccentric exercise (Journal of the International Society of Sports Nutrition, 2010; 7(1):30), stimulate the processes underlying muscle protein synthesis and improve strength gains that result from engaging in a resistance training program, especially when whey is consumed in close temporal proximity to resistance training bouts (International Journal of Sport Nutrition and Exercise Metabolism, 2006; 16(5):494-509). And, though these study results make bodybuilders and fitness enthusiasts reach for whey, Americans over the age of 40 should, as well. After this age, sarcopenia (the loss of muscle mass with aging) begins and progresses through life. A diet that incorporates high-quality proteins, like whey, in conjunction with resistance exercise, can help decrease this gradual loss of muscle tissue (Current Opinion in Clinical Nutrition & Metabolic Care, 2008; 11(1):40-44).

Wheys benefits for muscle tissue also extend to those trying to lose weight. Whey protein, when consumed as part of a higher-protein, reduced-calorie diet, may facilitate greater weight loss and alter the composition of weight loss in favor of fat as opposed to lean mass (Journal of  Nutrition, 2006; 135:1,903-1,910; Obesity, 2007; 15(2):421-429; Annual Review of Nutrition, 2009; 29:11.1-11.21; Journal of Nutrition, 2008; 138(4):698-702; American Journal of Epidemiology, 2009; 169(7):893-900). Wheys benefits for weight management are due both to its ability to enhance satiety (Arquivos Brasileiros de Endocrinologia & Metabologia,  2010; 54(1):45-51) and its role in helping maintain muscle mass while on a low-calorie diet.

Whey, or its individual proteins, may confer immune benefits, too (Journal of Nutrition, 2008; 138(12):2,392-2,398). Researchers theorize this occurs because whey protein can help the body produce a crucial immune-system antioxidant called glutathione.

Formulation

Along with wheys nutrition benefits, it is also a boon for formulators. Whey protein ingredients provide a natural way to enhance a food or beverage products nutritional value and protein content without adding significant calories. In addition, whey offers many functional benefits that improve the taste, texture, flavor and color of products. Whey proteins can emulsify and stabilize, improve flow properties, extend shelf life and enhance dispersability in dry mixes," notes Kimberlee Burrington, dairy ingredients applications coordinator, Wisconsin Center for Dairy Research, University of Wisconsin, Madison. Also, whey has gelling, foaming, emulsifying and browning capabilities in other products."

A variety of food and beverage products contain whey protein concentrates and isolates, including sports drinks (ready-to-drink and powders), confections, soups, snack foods, clinical nutrition products, weight management and diet products, and infant formulas. And, though one form of whey isnt superior to another, and the choice depends heavily on the application and end user, whey protein concentrate with a protein content of 80% and whey protein isolate are most commonly used in nutritional applications, while other types of whey and whey powder are more typical in specific applications such as confections and baked goods," according to Burrington. Demineralized whey and reduced-lactose whey are used as an ingredient in some infant formulas." Whey protein hydrolysates are most commonly found in infant formulas, clinical nutrition products and sports nutrition products. In addition, hydrolysates may be chosen over other whey protein ingredients for their gelling properties, heat stability and/or emulsification.

Whey is a high-quality complete protein that is backed by scientific research for its role in increasing satiety and facilitating muscle protein synthesis, making its benefits applicable to a wide range of people and important for use throughout the lifespan. In addition, the different forms of whey offer versatility, allowing formulators to choose the best form for the application while meeting consumer demand for higher-protein foods and beverages.

Marie Spano, M.S., R.D., CSCS, CSSD, is a nutrition communications expert and food industry consultant. Marie writes for popular press magazines and trade publications, has given cooking demos on NBC, ABC, FOX and CBS affiliates and helps companies formulate healthy products. For more information, visit mariespano.com.