Functional dairy foods and ingredients

This paper reviews current commercial developments in dairy functional foods and ingredients, assesses the health evidence for these products and discusses emerging trends in the area. The global functional food market is large and growing rapidly. Dairy-based functional foods were valued at more than US$5 billion in 2003. Milk is a major provider of important nutrients for humans, including calcium, protein and riboflavin, however, it is now recognised that dairy products and ingredients derived from milk and whey can provide functional food products with beneficial effects on human health, as well as nutritional benefits. In this review, the role of traditional dairy products (milk, yogurt, fermented dairy drinks, infant milk formulae, colostrum, cheese and ice-cream) as functional foods is examined. Functional dairy-derived ingredients are then assessed. Casein and whey proteins and their derivatives are discussed, including peptides able to exert anti-hypertensive and other bioactive effects, lactoferrin and lactoperoxidase able to exert anti-microbial effects, and growth factors used in sports health and for tissue repair applications including wound repair. Probiotic bacteria and prebiotic carbohydrates are commonly used in yogurts and fermented drinks, but, until recently, unequivocal evidence on their health-promoting properties was lacking. This review summarises the clinical evidence for a wide range of commercial strains of lactobacilli and bifidobacteria. Prebiotic ingredients derived'from lactose are described, and their ability to improve health assessed. The main products are galacto-oligosaccharides, lactosucrose, lactulose and lactitol. Processing issues for the manufacture of functional proteins and peptides, and for the manufacture of probiotic cultures and prebiotic carbohydrates are discussed. Future trends and issues facing the emerging functional dairy foods and ingredients sector include development of synergistic probiotic and prebiotic products (synbiotics); new prebiotic carbohydrates more able to mimic human milk oligosaccharides, novel prebiotic proteins and peptides; closer alliance with the glycoscience industry; the emergence of genetically modified milk product; probiotics as carriers of biologicals and vaccines; and the regulatory issues surrounding the introduction of health claims for new functional dairy foods. It is concluded that the current, intense commercial activity to develop new functional ingredients from dairy products will continue, and become more sophisticated as knowledge of human physiology and nutrition advances, particularly in relation to gastrointestinal microbiology and immunology.