Nutritional Benefits of Bifidobacterium Lactis in Dairy Products

Bifidobacteria are one of the most important probiotics in dairy products. They have positive effects on human health. Nutritional benefits of bifidobacteria are genetically determined and can be promoted with addition of prebiotics. The aim of the present study was to examine the properties of Bifidobacterium lactis in dairy products. Pasteurised milk, freeze-dried starter culture Bb-12 (Bifidobacterium lactis, Chr. Hansen, Denmark), syrup of lactulose (Duphalac^®, the Netherlands), and inulin (“Raftiline^®HP”, ORAFI, Belgium) were used in the experiments. The optimal concentrations of lactulose (2%) and inulin (4%) were established in preliminary studies, based on quality indices and nutritional value of fermented dairy products (Beitane, 2008). Amino acids, carbohydrates, such as lactose, lactulose and inulin, as well as cholesterol were determined during the study using appropriate analytical procedures. The enzymatic activity of bifidobacteria determines nutritional value of the fermented dairy products. Addition of 2% lactulose resulted in significant increase of some amino acid concentrations, such as leucine, phenylalanine, lysine and arginine concentrations (P < 0.05), compared with those in other treatments. The presence of prebiotics caused a decrease of cholesterol level by 35% and lactose content by 31% in fermented milk samples. The enzymatic activity of bifidobacteria should be promoted with addition of lactulose and inulin to increase nutritional value of functional dairy products.