Beverages now face the challenge of being not only flavorful, but also nutritious, oftentimes offering unique health benefits. Functional beverages now address active lifestyles, weight loss, lower-carb/higher-protein lifestyles and general nutrition.
With an already healthy image, dairy is an excellent solution for formulating flavorful and nutritious functional beverages such as sport drinks, energy drinks and smoothies. Dairy-based beverages provide superior nutrition, as dairy is a source of high-quality proteins, calcium, potassium and other nutrients. The fat in milk can also be a natural source of conjugated linoleic acid (CLA), which may offer health benefits. Dairy also provides an excellent vehicle for delivering probiotics, which research suggests may play an important role in intestinal health, immunity and other health issues. In addition, ultrafiltered (UF) milk provides the opportunity to create unique dairy-based beverages, such as lower-carb/higher-protein drinks.
Dairy Proteins Offer the Whole Package
Dairy proteins, such as casein and whey, offer all of the essential amino acids the body requires. Whey protein, in particular, has a high biological value compared with other proteins (104 for whey protein vs. 88-100 for eggs, 74 for soy protein and 54 for wheat). Biological value is a measurement of protein quality that expresses the efficiency with which the body uses protein.
Whether inherently present in a milk base or used as isolated ingredients, dairy proteins provide beverages not only with a source of high-quality protein, but also may add a variety of health benefits. Emerging research is uncovering the potential of dairy proteins to help in weight control and lean muscle preservation. Preliminary studies also suggest benefits in lowering high blood pressure and enhancing immunity. These benefits make dairy proteins ideal for a variety of functional beverages.
Weight management. Research suggests that higher daily intake of proteins and their components, especially the high amount of leucine found in dairy proteins, may help people lose fat while preserving lean muscle. Whey protein is also the highest natural source of leucine.
Sports nutrition. Dairy proteins provide a high concentration of branched chain amino acids (BCAAs) with little or no fat, cholesterol or lactose. BCAAs are unique among amino acids in their ability to provide an energy source during endurance exercise. The oxidation of amino acids, mainly BCAAs, can provide 10% to 15% of the total energy required during exercise.
Cardiovascular health. Various components of dairy proteins may offer advantages in reducing elevated blood pressure.
Protection against infections and viruses. Dairy proteins contain several components that may help the human body protect itself against toxins, bacteria and viruses. For example, lactoferrin, an iron-binding whey protein, may increase iron absorption and transport, enhance immunity and stimulate growth of beneficial bacteria in the intestinal tract. Further, immunoglobulins have shown antimicrobial activity and may neutralize toxins and viruses.
Probiotics' Positive Appeal
Drinkable yogurts and refrigerated smoothies offer one of the best incremental growth opportunities for beverages, opening the door to more widespread use of probiotics. "Beverages marketed largely for health-as opposed to largely for convenience or fun-are the best match for probiotics for success," according to Mary Ellen Sanders, consultant, Dairy and Food Culture Technologies, Centennial, CO. "Drinkable yogurts are the most obvious choice for probiotics, but kefir seems to be really catching on, too. Blended smoothie-type drinks (mixed with fruit juices) could also be quite successful."
Probiotics are a perfect fit for these dairy-based beverages, as dairy is an excellent vehicle to deliver beneficial bacteria such as Bifidobacterium and Lactobacillus species. Consumption of probiotics with dairy foods such as milk, yogurt and cheese buffers stomach acid and increases the chance that the bacteria will survive into the intestine. Research funded by America's dairy farmers is exploring potential synergistic effects between components in dairy foods and probiotic cultures.
The healthful properties of probiotics also work well with the healthful properties of dairy beverages. "I think the concepts of immune support, allergy prevention or symptom control, and prevention of infection are easy to market to health-conscious people," said Ms. Sanders.
Probiotic cultures have been shown in a variety of test systems to stimulate certain cellular and antibody functions of the immune system. Animal and some human studies have shown an effect of yogurt or lactic acid bacteria on enhancing levels of certain immunoreactive cells (e.g. macrophages and lymphocytes) or factors (cytokines, immunoglobulins and interferon). In addition, some studies have shown improved survival of pathogen-infected laboratory animals consuming probiotic cultures as compared to animals consuming a control diet.
Research in Finland suggests that exposure to probiotics early in life may decrease the risk of allergy. One particular study reported a 50% drop in the incidence of recurring atopic eczema in infants receiving a Lactobacillus rhamnosus GG supplement.
When formulating dairy beverages with probiotics, several factors need to be considered. The farmer-funded California Dairy Research Foundation and Dairy and Food Culture Technologies (www.usprobiotics.org) recommend looking for documentation of type of bacteria (genus and species), potency (number of viable bacteria per dose), purity (presence of contaminating or ineffective bacteria) and the extent of research that has been published on health effects.
Ms. Sanders says stability is also crucial. "It is important that the target dose is maintained through the end of shelf life," she said. "Technical challenges include acidic dairy products, products, which suffer temperature fluctuations during storage, and other ingredients or exposures (e.g., a lot of oxygen), which are inhibitory to bacterial survival." All of these factors need to be understood when using probiotics in dairy beverages.
Dairy's Special Fatty Acid
Conjugated linoleic acid (CLA) is a fatty acid naturally present in cow's milk and certain animal meats, particularly beef and lamb. Emerging research indicates that milk-derived CLA might hold anti-cancer properties and positively impact cardiovascular health.
Studies examining cancer cells in animals demonstrate that the form of CLA in milk is effective against many types of cancer. More specifically, biomedical studies with animal models have shown that CLA is among the most potent naturally occurring anticarcinogens. Additional research is required to determine the potential proactive effect of CLA on humans, however.
Other research suggests CLA may reduce the risk of atherosclerosis. In investigations with biomedical animal models, the form of CLA in milk causes shifts in plasma low-density lipoprotein (LDL) and high-density lipoprotein (HDL) cholesterol that are associated with a reduced risk of coronary heart disease. The isomer of CLA in ruminant fat does not affect body fat or body composition.
Compared to all other foods, dairy products are the major natural source of CLA. The CLA in milk is produced by the cow during the process of milk synthesis from a precursor fatty acid made by the microbes in a cow's stomach.
Research is currently underway to produce milk with higher levels of CLA by modifying dairy cow feed. Scientists at the farmer-funded Northeast Dairy Center at Cornell University are presently testing milk with higher levels of CLA to determine sensory characteristics such as appearance, flavor, aroma and texture.
Calcium, the Essential Nutrient
Adding calcium in the form of nonfat dry milk, dairy calcium or a milk mineral complex brings added benefits to beverage formulations. This mineral is not only essential for bone health; it has also been linked to the maintenance of healthy blood pressure and reduction of dental cavities.
A recent study showed that people on a reduced-calorie diet who consumed three servings of milk, cheese or yogurt each day lost significantly more weight and more body fat than those who just cut calories, while consuming little or no dairy. The mix of nutrients found in dairy foods, especially calcium, may be responsible for helping the body break down and burn fat.
Refining Dairy for Lower-Carb Beverages
Ongoing farmer-funded research is poised to boost innovation in dairy-based beverages. Ultrafiltration removes part of the lactose, soluble minerals and water from whole or skim milk. The resulting ultrafiltered (UF) milk, in both fluid and powdered forms, offers opportunities for lower-carb beverages. The milk protein concentrates generated from ultrafiltration are ideally suited to producing lower-carb dairy-based beverages and serving as protein ingredients in functional beverages.
Ultrafiltration, combined with other technologies, also can result in ultrafiltered fluid milk with an extended shelf life and a lower carbohydrate content. This can stand alone as a unique dairy-based beverage or be used in novel dairy drinks such as smoothies or fermented dairy beverages.
Dairy's presence in the functional beverage segment will only grow stronger as ultrafiltration technology advances and research continues to unveil the unique health benefits of the components in dairy. From proteins and probiotics to nine essential vitamins and minerals, dairy-based beverages have much to offer today's health-conscious consumer.NW
About the author: Bill Haines, PhD, is vice president, product innovation, Dairy Management Inc. (DMI), Rosemont, IL. DMI is the domestic and international planning and management organization that builds demand for U.S.-produced dairy products on behalf of America's dairy farmers. For more information on using dairy in beverages, contact the DMI Technical Support Hotline at 800-248-8829.