IFT 2000 MEETING HIGHLIGHTS
RELATED TO FUNCTIONAL DAIRY FOODS

Unique hydrolyzed whey protein isolates with antihypertensive activity

L. NELSON¹, A. Rao, and P. Olson. (1) Applications, Davisco Foods International, Inc., 11000 West 78th St., Suite 210, Eden Prairie, MN 55344

Hydrolyzed whey protein isolate (WPI) is a highly purified ingredient, hydrolyzed under controlled conditions to obtain unique functional and nutritional properties. The enzymatic hydrolysis process produces protein ingredients designed for nutritional, dietetic and medical foods. The hydrolysis of the WPI manufactured using ion-exchange technology produces antihypertensive (bioactive) peptides, which suppress angiotensin converting enzyme (ACE). ACE catalyses the degradation of angiotensin I into angiotensin II, a strong vasoconstrictor. Hypertension is considered to be the most important cause of human deaths in industrialized countries. The study of the physiological mechanisms responsible for hypertension has lead the pharmaceutical industry to propose ACE-inhibitory substances. The inhibitory effect of natural peptides has been related to their binding at the active site of ACE. While other manufacturers have produced hydrolyzed whey protein ingredients, laboratory tests have shown that Davisco's hydrolyzed WPIs provide uniquely effective peptides for the ACE-inhibiting activity. ACE-inhibitory activity values or IC₅₀ (concentration of protein hydrolysate material inhibiting 50% of ACE activity), as determined in vitro, are in the range of 0.30 to 0.50 mg/ml, compared to 0.96 to 1.3mg/ml for other commercially available whey protein hydrolysates. The enzymatic hydrolysis of WPI leads to a synergistic effect in terms of ACE-inhibitory potential of the hydrolysates obtained. It appears that the synergy could result from unique compositional characteristics brought by the ion-exchange process in combination with the use of specific enzymes. These characteristics are responsible for specific functional and sensory properties. The molecular weight distribution of the commercial hydrolysates is not only the result of the nature of the protein and of the specificity of the enzyme used, but is also strongly affected by the severity of the heat treatment applied for enzyme inactivation at the end of the reaction. The results are food additives to combat one of the nation's most destructive health problems.

Novel Milk Protein Concentrate with Biological Activity and Nutraceutical Functions

D. A. GINGERICH¹, Y. Z. Lee, K. Kiser, J. D. Strobel, J. Lange, C. McPhillips, J. P. Fuhrer, and R. C. Stohrer. (1) SMBI, Suite 400, 6954 Cornell Road, Cincinnati, OH 45242

We have, over the years, described therapeutic benefits of milk, developed proprietary methods of enhancing its bioactivity, and verified health benefits in clinical trials. Traditionally, the bioactivity in milk is attributed to high MW proteins including antibodies, casein, lactoferrin, TGF-b2, etc., with their well-known biological effects. We have discovered that milk also contains novel, low MW, dialyzable, non-protein micronutrients that are bioactive, and have demonstrated anti-inflammatory and anti-hypertensive activities of these micronutrients.

We recently developed a proprietary method of producing milk protein concentrate which preferentially concentrates both high and low MW classes of bioactivity in a single nutraceutical ingredient, Stolle Milk Protein Concentrate (SMPC). We have tested SMPC for anti-inflammatory and anti-hypertensive activities in standard pharmacological models including the rat paw edema test, the 12-O-tetradecanoyl-phorbol-13-acetate (TPA) mouse ear inflammation model, and the spontaneously hypertensive rat (SHR) model. To summarize our results: 1. Rat paw edema: SMPC inhibits swelling significantly (p<0.05) at doses as low as 10 mg/kg when given by gavage one hour before carrageenan challenge. 2. Mouse ear edema: Organic extracts of SMPC applied topically to TPA-stimulated ears inhibit swelling by 60% compared to untreated controls. 3. Blood pressure: SMPC fed to SHR rats at 2% wt/wt of chow significantly (p<0.001) reduced blood pressure over the 6-week study period.

These and other results indicate that bioactivity in milk, previously shown to be clinically useful, has indeed been captured in SMPC. SMPC, therefore, has nutraceutical potential for inflammatory conditions (e.g. arthritis), cardiovascular health, etc. as an ingredient in food or beverage products.

Lactic Acid Bacteria and Health

T. R. KLAENHAMMER, Department of Food Science / Southeast Dairy Foods Research Center, North Carolina State University, 339 Schaub Hall, Box 7624, Raleigh, NC 27695-7624

Dairy foods fermented by lactic acid bacteria have long been held in special favor as safe and nutritious foods that may also elicit positive effects on health and well being. Archaic texts from Irac dating back to 3200 BC hold references to cheese, butter, and yoghurt indicating that fermented dairy foods have long been part of the daily human diet. Soured milk bore the first pure bacterial culture (Bacterium lactis, Lister 1873) and later the probiotic concept. Eli Metchnikoff (1904) attributed the long and healthy lifestyle of Bulgarian peasants to the consumption of fermented milks. Over the last 30 years, intensified efforts to identify and characterize lactic acid bacteria have revealed their many critical roles in dairy foods, including: acid production, texture development, flavor generation, preservation, and synthesis of B-vitamins. Select members of the lactic acid bacteria have now been implicated through clinical studies to provide resistance to enteric pathogens, stimulate the immune system, and help maintain a balanced gastrointestinal microflora. Advances in microbiology, molecular biology and genomics, focused on dairy lactic acid bacteria, have begun to elucidate their roles and interactions within complex fermentation ecosystems and the gastrointestinal tract. Genetic technologies can further be exploited to expand upon the beneficial activities of lactic acid bacteria through metabolic engineering and/or expression of novel products, such as digestive enzymes, vaccines, or other bioactive compounds. The future linkage of lactic acid bacteria and health holds considerable promise as a result of their long and safe consumption through dairy foods, and their potential to deliver novel bioactive molecules that positively impact human health and well being.

Researching the genetic basis for the nutritional and functional aspects of dairy foods

B. GERMAN, Department of Food Science and Technology, University of California at Davis, 212 Food Sci & Tech, Davis, CA 95616

The scientific future that will follow the arrival of the human genome will ascribe biological function to each gene. In the field of nutrition, as in pharmaceuticals, the genome is being viewed first as the ultimate source of molecular and biochemical targets for the actions of nutrients. However, the genome in one respect can be viewed as the ultimate source of nutrients. Milk is the only bio-material that has evolved for the sole purpose of nourishing growing mammals. In fact, most plants evolved with an opposite pressure-to avoid being consumed by animals. Survival of mammalian offspring has exerted a strong selective pressure on the lactation process, and a very complex spectrum of molecules has already been discovered that are produced in the mammary gland that function uniquely to improve the nutritional status of infants. Researchers at UC Davis are now using the available human genome to define genes by lactation-specific selection criteria. This 'milk genome' is defining in genetic terms what evolution has achieved as a nutritional food for humans, milk. The milk genome so obtained will be the database to focus research on the functional value of the components of milk, both direct gene products (proteins, growth factors, peptides) and metabolites that are the consequences of milk genes (specific carbohydrates, lipids, transporters, etc.).