Novel probiotic whey cheese with immobilized lactobacilli on casein

In the present study, the use of thermally-dried immobilized lactobacilli (Lactobacillus casei ATCC 393 and Lactobacillus delbrueckii ssp. bulgaricus ATCC 11842) on casein was evaluated for the production of a novel dried whey cheese. Cheeses with thermally-dried free lactobacilli cells and with no starter culture were also produced, for comparison reasons. The main physicochemical and microbiological characteristics of a novel whey cheese were determined during ripening at 20 °C until day 60. The results clearly demonstrated that the use of free and immobilized L. casei and L. bulgaricus on casein positively affected the production of dried whey cheeses. More specifically, their use led to novel whey cheeses with improved quality, as resulted by sensory evaluation and SPME GC/MS analysis of aroma related compounds, extended preservation time and protection from spoilage and pathogens. Whey cheeses microbiota was dominated by lactobacilli and mesophilic and thermophilic lactococci. Counts of coliforms, enterobacteria and staphylococci were significantly reduced in whey cheese produced with thermally-dried lactobacilli cultures. The use of cultures, like those proposed in the present study, may have a great potential in dairy technology for the conversion of low quality whey cheeses to novel probiotic foods with improved characteristics.