Production and Maintaining Viability of Probiotic Micro-organisms in Dairy Products

The stability of probiotic cultures has been seen as an issue for dairy manufacturers and consumers and this chapter reviews the technical and scientific aspects of probiotic dairy products. Probiotic micro-organisms are shown together with their main metabolic products. This provides some information on their possible role in flavour production, but it should be noted that the traditional lactic acid bacteria (LAB) (i.e. starter cultures) are mainly responsible for much of the flavour and aroma. For probiotic products, micro-organisms are selected for their various health benefits. A wide range of fermented milk products is made in many different countries. The classical example is yoghurt. Frozen yoghurt technology may be adopted for the inclusion of probiotic cultures into ice cream and frozen desserts. The viability of probiotic bacteria in yoghurt depends on the strains used, interaction between species present, production of hydrogen peroxide due to bacterial metabolism, and the final acidity of the product.