Milk Composition – The Future

Abstract

AbstractThe papers presented at this Conference have highlighted the many exciting and challenging developments occurring in relation to milk composition within the production, processing and retail sectors. Historically, review papers considering future issues in relation to milk composition have focussed on opportunities to manipulate milk constituent composition. However, the overriding issue at present, in relation to milk composition in the broadest sense, concerns consumer perception of milk and dairy products. This is particularly the case with respect to : food safety; human health and; the naturalness and wholesomeness of milk and milk products. Food safety has become a key issue for consumers given current concerns over BSE, Escherichia coli 0157, antibiotic residues and dioxin contamination. Consequently, quality assurance schemes and traceability of supply from “farm to plate” have, or will become, essential features of the liquid milk/dairy product sector.Consumer concerns regarding effects of consumption of milk/dairy products on human health have historically centred on the highly publicised link between fat consumption, particularly saturated fat, and coronary heart disease. However, more recently the less well publicised beneficial effects of milk/dairy product consumption on human health are now being recognised. These include the importance of milk and cheese as calcium sources for bone growth, which can reduce the risk of osteoporosis in later life, the positive effect of milk consumption on dental health (particularly when substituted for high–sugar soft drinks in young children) and anticarcinogenic and antiatherogenic effects mediated through the conjugated linoleic acid (CLA), butyric acid and sphingomyelin components within milk and dairy products. Increased emphasis on generic advertising of milk is essential to highlight these positive features to opinion–formers and consumers, especially when contrasted with the advertising budgets associated with competing products.Major shifts in consumer consumption patterns have occurred in the last 30 years, with increased demand for low fat products, ready meals etc. and this has led to changes in milk processors’ requirements as assessed in terms of raw milk composition and properties. Alongside this, technological advances at the production level have facilitated opportunities to accelerate the rate of genetic change in the dairy herd and to modify/adapt feeding systems to better meet processor requirements. Further opportunities exist to increase fat plus protein yield whilst improving the protein :fat ratio through genetic improvement, but opportunities for genetic improvement in the composition of protein and fat fractions appear more limited. Alteration of protein, and particularly milk fat composition (e.g. enhanced unsaturated fatty acid and CLA contents) can be much more readily attained by modifying the diet of the dairy cow, and large scale projects using this approach are already delivering improved products to the consumer. One of the most excitingareas in terms of use of milk as a raw material relates to the production of both natural and induced bioactive components. In future, the mammary gland of the dairy cow may well be viewed as a bioreactor with the potential to synthesise large quantities of high value proteins. Use of transgenics, whilst potentially facilitating production of high value therapeutic or food ingredient components, is likely to be limited by consumer resistance to genetically modified dairy cows.Development of niche markets for tailor–made milks and milk products (including organic produce), achieved through dietary manipulation, will require increased vertical integration between animal feed suppliers, milk producers, milk processors and food retailers. Increasing consideration in the future will also have to be given to the potential change in milk composition/processing characteristics mediated through changes in production systems, such as seasonality of calving, use of extended lactations and adoption of new milking systems e.g. robotic milking. Finally, the concept of naturalness and wholesomeness of milk and dairy products is also a major consideration for the consumer. We must be careful in adopting new technologies, whether at the level of on farm production e.g. animal breeding and feeding, or at the processing level e.g. food irradiation and high pressure processing, to ensure that the attributes of naturalness and wholesomeness of milk and milk products are retained.