Influence of bifidobacteria on some synbiotic beverages

ABSTRACT

The bioconversion of whey is an interesting process from the view point of human nutrition, especially for therapeutic purposes, with regard to economy, and the advantage for reducing environment pollution. Bioconversion of heat treated whey for preparation of synbiotic beverages was standardized by utilization of Bifidobacterium lactis Bb-12, 3% fructose and 1.25% dried Jerusalem artichoke known as tartofa to contain 70% inulin. Samples were then divided into four treatments and the following components were added as follow 1] control without any additives. 2] 10% fresh tomato juice. 3] 10% yellow carrot pulp. 4] 1% Green tea [packets] infused during whey heat treatment then removed when the temperature reached 40°C. The acidity, lactose, protein, freezing point and the viable bifido counts were followed over successive intervals during 15 days of refrigerated storage. Sensory evaluation and organic acids [short chain fatty acids] were monitored on the stored products. Results revealed that such additions increased bifido viable cell numbers. The green tea fermented beverage was the most acceptable. A progressive decrease was detected for lactose and protein, in contrast to titratable acidity and freezing point which increased. Lactic, acetic, formic and citric were the main organic acids in all treatments, while oxalic acid was high in the carrot beverage and malic acid was high in the green tea beverage