Food--leading the way (AIFST) and dairy products in human health and nutrition, Melbourne, Australia, 24-27 August 2003.

Professor Bruce German, from the University of California and Nestle Research Centre Switzerland, presented two keynote addresses. Professor German explained how milk delivers a myriad of food ingredients that provide health benefits. He argued that milk was designed through selective Darwinian evolutionary pressure to provide benefits to health and improve the competitive success of the offspring. This is now being recognised through the development of strategies to promote health using milk, such as stimulating beneficial microflora, enhancing the absorption of nutrients, and educating the immune system to the presence of potential pathogens. It is interesting to note that in Europe, dairy products account for approximately 60% of all functional food products on the market. In fact, the endeavour to uncover functional food ingredients was taken up by Professor German in his second address on the implications of genomics for food and nutrition.

To date nutrition science and the development of foods with functional components has followed the highly successful pharmaceutical model to determine the mechanism by which a disease can be cured by a bioactive isolate. Disease is a clear target for research and the efficacy of treatment through drugs is based on reversing existing disease or preventing disease. Professor German suggests that this paradigm is not appropriate for food and nutrition science. The physiological targets have not yet been determined for healthy individuals. Nutrition mechanisms often involve synergies with bioactive components within and/or between food groups, which a reductionist pharmacological approach may not detect. Nutrition and food sciences will go beyond genomics to proteinomics and metabolomics to understand how foods influence gene expression, metabolism and functions within individuals. Those fields of science with the -omics suffix are both global in their ability to determine health measures and associated mechanisms, as well as specific in their potential to determine individual dietary prescriptions based on a specific genetic profile (the hyphen omics suffix was coined by German and French cytologists between 1907 and 1919 to signify cellular organelles collectively) (1). Professor German stated that omic technologies are now commercially available in kit form and predicts that this field will do for nutrition science in the twenty-first century that which chemistry did in the twentieth century. Subsequent speakers guided delegates through milk bioactive isolates and related health implications as well as detailing some innovative functional food developments.

Tony Scammell, a marketer and employee of Numico Research, reviewed recent clinical studies in power and endurance studies which have shown that by supplementing athletes' diets with colostrum protein powder they have demonstrated improvements in recovery and performance, as well as a reduction in respiratory tract infections, when compared to whey protein. To this end Numico have developed a colustrum protein powder (intact[R]) and positioned dairy in the sports market. Mr Scammell believes that the market for optimal nutritional support in sport is significant. About four million adults frequently undertake sport in Australia. A further 3.5 million people engage in sport and physical activity, making a total of 55% of adults who engage in activity or sport.

Another significant market is in foods with a role in weight management. Individuals who are trying to lose weight often reduce dairy foods in their diet. Recent evidence provided by Dr Douglas Dirienzo of the National Dairy Council, USA, suggests that dairy may be part of the solution not the problem. Results of the recent CAR-DIA epidemiological trial reported the inverse relationship between dairy and obesity. Animal and in-vitro studies have offered some plausible explanations. For example, low dairy/calcium intakes result in the flow of calcium into fat cells as a result of increased 1[alpha], [(25-OH).sub.2]-[D.sub.3] and other calcium regulating hormones. Higher adipocyte calcium concentrations result in an upregulation of lipogenic pathways while regulating lipolytic pathways in the adipocyte. By eating a diet high in dairy the opposite effect occurs.

The old adage that milk is good for our bones and teeth was given more weight when research was presented by Dr Alisa Goulding and Professor Eric Reynolds. Previous research has focussed on the calcium content of the diet and bone health, whereas more recently other milk nutrients, such as bioactive peptides have been identified as markers of bone health. These peptides have been shown to affect the osteoblasts and osteoclasts directly. Dr Goulding, from the Department of Medical and Surgical Sciences, University of Otago, NZ, presented strong evidence showing that children who were poor milk drinkers tended to be shorter in stature and overweight, and they fracture more bones than their milk drinking counterparts. Again the point was made that to make a strong skeleton early in life, milk is important and the reasons may not be due to calcium alone.

Professor Reynolds from the University of Melbourne presented on the science behind the development of a functional food product successful in combating dental carries. Recaldent[TM] is a commercially available ingredient in a range of oral health care products. Dental caries (tooth decay) remains a public health concern despite the success of fluoride added to the water supply. There is a body of literature showing the anticariogenic effect of dairy products. Through animal, and in-situ human models the effect can be attributed to the multiphosphoseryl-containing sequences of casein and their ability to stabilise calcium phosphate, forming CPP-ACP nanocomplexes (Recaldent[TM]). The CPP-ACP localise at the tooth surface and not only prevent demineralisation but have been shown to remineralise the enamel surface.

The commercial applications of dairy based products such as Recaldent[TM] and intact[R] are targeted to functional food markets. However, Geoff Regester, an economist from GroPep Ltd, SA, outlined a very interesting case study in the development of a nutraceutical--nutrient with therapeutic applications. GroPep uses cheddar cheese whey as a novel ingredient source material for the development of a human therapeutic--whey growth factor extract (WGFE). In-vitro studies and early clinical trials have suggested that WGFE is an effective treatment in wound healing and has potential applications in managing ulcers secondary to radiotherapy. However, to register this product as a drug requires stringent pharmaceutical-grade manufacturing, through pre-clinical testing to multi-centre clinical trials. There are major cost and regulatory barriers to overcome and commercial applications may be five years away. One option available is to position this product as a functional food, based on the existing evidence, while undertaking further trials and development.

The quest to find the diet (or dietary components) with anti-cancer properties has been fierce over the last two decades. Dr Peter Parodi, of the Human Nutrition Program, Dairy Australia, presented research on a number of milk fat components that have demonstrated anti-cancer potential in animal models of carcinogenesis. Recent studies in animal models provide insight into the possible mechanisms of the cancer fighting properties of milkfat components such as conjugated linoleic acid, Vaccenic acid, sphingomyelin and 13-methyltetradecanioc acid. In addition milk fat also contains vitamin A and [beta]-carotene, which are known anti-cancer agents. Emerging areas of interest include components like [beta]-ionone, phytol and gossypol, which may also prevent cancer.

The dairy industry has been very innovative in the functional food market place. In Germany for example, there is a brand of drinking yoghurt where the live culture is not delivered through the beverage, but is contained in the straw and delivered as the fluid passes by. Using a liberal definition of functional foods (including whole, unfortified foods with purported health benefits) reveals that dairy foods represented 60% of the overall market. Despite the intense interest in functional foods the estimated market for food products with health benefits still only represented 1% of the global food market and this has direct implications for the dairy industry.

Moira Hilliam, a market researcher from the UK, had recently completed a study into consumer opinion on functional foods, throughout Germany, France and the UK. She stated that the future of functional food development will be based on five major principles--self-care, positive nutrition, simplicity and convenience, individual needs and part of everyday life. Overall, she found that consumers recognised the important role of diet, although confused by what this means. In addition consumers have a high interest in claims. She considers that consumers did not identify with the term functional foods and that a more appropriate lay term may be 'well-being' foods to reflect a more general health theme.

With the aid of genomic, proteinomic, and metabolomic methodologies, our scientific quest to produce novel foods with bioactive constituents, may provide further proof to the doctrine of synergy--that the whole is more than the collective sum of the parts.

Reference

(1.) Kirkham S. The omic explosion--A brief history of -ome. The Biochemist. 2003:6.

Craig S Patch APD 

ARC Key Centre for Smart Foods

University of Wollongong, NSW