Technological aspects related to the use of bifidobacteria in dairy products

Abstract

Dairy-related bifidobacteria are already used in a wide variety of probiotic dairy products including milk, cheese, frozen yoghurt-like product and ice cream. The survival of bifidobacteria in fermented dairy products depends on varied factors such as the strain of bacteria used, fermentation conditions, storage temperature, and preservation methods. Growth of bifidobacteria in milk is often slow or limited compared with lactic acid bacteria used in fermented dairy products, and this appears partially due to low proteolytic activities. When manufacturing cheese or yoghurt-like pro- duct, addition of probiotic cultures to the normal starters generally results in slower growth of the probiotic strains than if they were added alone in milk. The use of higher inocula of bifidobacteria and the addition of growth promoting factors as a nitrogen source should further enhance the growth and viability of the bifidobacteria. Although the most common processing stage at which to add the bifidobacteria to the milk would be in conjunction with the other starter cultures, other alternative processing protocols have been successful in incorporating the bifidobacteria into cheese and cultured dairy products. The success of the incorporation of bifidobacteria into cheeses is dependent on the bifidobacteria strains, the activity of lactic acid bacteria used in the manufacture of the cheese, the composition of the cheese, and the conditions of processing and ripening. Changes in the chemical composition and the texture of the fermented products can occur in cheeses and fer- mented milks without affecting sensorial properties. Bifidobacterium / yoghurt-like product / cheese / viability / stability