The Diversity of Dairy

Three daily servings of milk, cheese, or yogurt are recommended to maintain strong bones and healthy bodies. Recent research has linked dairy to sports nutrition, more specifically dairy’s ability to build lean muscle. Shirreffs et al. (2007) indicated that consuming skim milk after exercise may promote recovery and rehydration better than water or an isotonic sports drink. Hartman et al. (2007) showed that for young male weightlifters, drinking fat-free milk after resistance exercise had a greater effect on helping to increase lean body mass compared with soy or carbohydrates.

Dairy provides nine essential nutrients, including calcium, potassium, phosphorus, protein, vitamins A, D, and B-12, riboflavin, and niacin (niacin equivalents). In the past, dairy’s benefits were associated predominantly with calcium and vitamin D, but recent research shows that other dairy components such as whey, milk peptides, and milk fat have positive effects on bone health, sports nutrition, digestive health, and weight management.

Calcium and Vitamin D
In October 2008, the Food and Drug Administration approved two new health claims that promote the link between calcium or calcium and vitamin D and a reduced risk of osteoporosis. Foods that are excellent sources (20% or more of the Daily Value per standard serving) of calcium and foods that are excellent sources of calcium and vitamin D can now bear claims about the relationship between these nutrients and a reduced risk of osteoporosis.

In addition to bone health, calcium has been shown to benefit weight management. Zemel et al. (2005) showed that among 34 obese adult subjects, those who consumed a calcium-rich, reduced-calorie diet (three servings of yogurt a day for 12 weeks) lost 22% more weight, 66% more body fat, and 81% more trunk fat compared with those who consumed just the reduced-calorie diet with little or no dairy.

Recently, the benefits of vitamin D have been widely reported. At the Food Technology Presents Wellness09 conference in March 2009, speakers addressed vitamin D’s role in bone health, cancer, and diabetes, and gave suggestions for increasing recommended amounts for vitamin D. In addition, at the IFT Food Expo® in June 2009, presenters at the symposium, “Vitamin D and Health: Implications for the Food Industry,” reviewed the latest research on the biology of and requirements for vitamin D, presented the use of existing and new chemical forms and complexes with vitamin D, and discussed potential and rationale for additional food fortification with vitamin D.

Milk Proteins
Milk protein concentrates (MPC) contain undenatured forms of both casein and whey protein. The high-protein, low-lactose ratio of MPC makes it a useful ingredient for protein-fortified beverages and foods and low-carbohydrate foods.

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In May 2009, at the Vitafoods International conference in Geneva, Switzerland, Glanbia Nutritionals, Monroe, Wis. (phone 608-329-2800, www.glanbianutritionals.com), showcased its Solmiko range of milk protein concentrates and isolates. The ingredients provide both casein and whey in the same ratio found in milk (80:20). The milk proteins provide slow-release micellar casein and fast-release whey protein, which are naturally high in colloidal milk calcium, to deliver an immediate peptide-rich boost. The ingredients tap into the well-known benefits of dairy proteins, including satiating properties and developing lean muscle mass. According to the company, the blend of both casein and whey proteins prevents muscle breakdown by night and helps repair muscle damage by day.

Another MPC, MicroLactin™ from Stolle Wellness, Cincinnati, Ohio (phone 513-489-7997, www.stollewellness.com), is believed to benefit joint health by altering the expression of inflammatory signals and modifying the movement of inflammatory cells. Zenk et al. (2002) showed in a double-blind, placebo-controlled study that the bioactive MPC had a positive effect on easing joint pain.

Last year, Stolle Wellness announced that it had developed improved processing methods that preserve the bioactivity of milk proteins and the health benefits they provide when used in foods that are processed using heat. The company tested the processes successfully with a variety of foods and found that milk proteins, which had been added to the foods, maintained their bioactivity for the expected shelf life for each product type.

Whey Protein
Whey protein is said to contribute to muscle synthesis and is used in many sports nutrition products, thanks in part to its amino acid profile, which is almost identical to that of skeletal muscle. In addition, whey protein is a source of naturally occurring branched-chain amino acids, including leucine, which has the ability to initiate muscle protein synthesis, according to information from Dairy Management Inc.™ (DMI), Rosemont, Ill. (phone 800-248-8829, www.innovatewithdairy.com).

Whey protein can play an important role in improving body composition in active adults, as well as aid in exercise recovery.Research shows that consuming whey protein in combination with resistance exercise can boost the rate at which the body makes lean muscle, which may improve body composition (Tipton et al., 2004; Tipton et al., 2007). In addition, Tang et al. (2007) found that drinking an isotonic beverage with 10 g of whey protein and 21 g of carbohydrate following resistance exercise stimulated the repair and rebuilding of lean muscle necessary to support muscle recovery more than drinking a beverage containing an equal amount of carbohydrate alone.

Whey protein is believed to have a positive effect on satiety. “Calorie-for-calorie, protein has been shown to lead to greater satiety than carbohydrates or fats,” said Matt Pikosky, Director of Research Transfer, DMI.

A patent-pending, all natural partially hydrolyzed whey protein, Prolibra®, from Glanbia Nutritionals, Monroe, Wis. (phone 608-329-2800, www.glanbianutritionals.com), has been shown to be a potential solution to weight loss. The ingredient combines the beneficial properties of leucine, bioactive peptides, and minerals to effect changes in body composition and reduce glycemic response. A recent study showed that the addition of Prolibra to a liquid meal in the dose range of 6.1–24.4 g would result in a reduction of the glycemic index value of the product by approximately 7.6–37.8 GI units (Glanbia, 2008). Three Prolibra dose levels were used to determine the glycemic index–lowering potential of the ingredient within a liquid meal: 6.1 g, 12.2 g, and 24.4 g. In addition, Frestedt et al. (2008) showed that the whey protein complex reduced body fat and retained lean muscle mass in a 12-week study of 106 adults. The subjects consumed either a Prolibra or isocaloric ready-to-mix beverage 20 min before breakfast and 20 min before dinner on a diet based on a caloric reduction of 500 calories per day. While subjects in both groups lost weight, those who supplemented their diet with Prolibra lost an average of 6.1% of their body fat mass while the subjects who consumed the control diet lost an average of 3.5%.

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Milk Fat
The University of Reading in June 2008 hosted a symposium, “Scientific Update on Dairy Fats and Cardiovascular Diseases,” organized and facilitated by the International Dairy Federation’s Standing Committee on Nutrition and Health. The information presented at this symposium highlighted the fact that despite the contribution of dairy products to the saturated fatty acid composition of the diet, there is no clear evidence that dairy food consumption is consistently associated with a higher risk of cardiovascular disease (Lock et al., 2008).

At this year’s IFT Food Expo, the presentation “Unique Aspects of Dairy Fat in Health” focused on three specific potential benefits of milk fat components. Robert Ward, Assistant Professor of Nutrition and Food Sciences at Utah State University, presented research on the potential health benefits of milk fat globular membrane on inflammation and colon cancer. Spencer Proctor, Professor in the Dept. of Agricultural, Food & Nutritional Science at the Alberta Diabetes Institute in Edmonton, Alberta, Canada, presented his research on the potential benefits of vaccenic acid, which is the primary trans fat found in dairy, on metabolic syndrome. Eva Warensjo, Senior Research Fellow at the Smart Foods Centre at the University of Wollongong, Australia, presented promising new research indicating that milk fat intake is inversely related to myocardial infarction and components of metabolic syndrome, primarily in women.

Prebiotics
A GRAS dairy-derived prebiotic, Vivinal® GOS, from Friesland Foods Domo USA Inc., Zwolle, the Netherlands (phone +31-38-46-77-444, www.domo.nl), provides benefits for immunity, digestive health, and calcium adsorption. The ingredient is rich in galacto-oligosaccarides (GOS) and is derived from lactose. Compared to other oligosaccharides, GOS or galacto-oligosaccharides most closely resemble the oligosaccharides present in human milk, according to the company. Vivinal was showcased at this year’s IFT Food Expo in orange juice and a fruit and nut granola bar. The prebiotic replaced some of the sugar syrup, offering reduced calories, low glycemic index, and other health benefits.

Expect more innovation to come from dairy-derived ingredients. In early 2009, industry, government, and academia united to form the National Dairy Research Program (NDRP). Participants include DMI, the National Dairy Council®, U.S. Dept. of Agriculture’s Agricultural Research Service, and the Dept. of Defense Combat Feeding Program—Natick Soldier Research, Development and Engineering Center. NDRP’s mission is to enhance collaboration and partnerships around dairy product and ingredient research. Product research priorities will include consumer demand-driven dairy foods, longer shelf-life dairy products, milk components as enhancers of nutrition and health, enhanced health and functional products through bioprocessing, and dairy food safety. Nutrition research priorities will include obesity prevention, food composition, and dietary guidance.

Linda Milo Ohr,
Contributing Editor,
Denver, Colo.
[email protected]

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