Production and shelf-life studies of low cost beverage with soymilk, buffalo cheese whey and cow milk fermented by mixed cultures of Lactobacillus casei ssp shirota and Bifidobacterium adolescentis

A study was performed to develop a fermented milk beverage with the aim to increase the potential application of buffalo cheese whey and soymilk. A mi xed substrate was prepared by selective combination, which contained buffal o cheese whey 35%, soymilk 30% and cow milk 35%. The substrate mixture was fermented by a mixed culture of Lactobacillus casei shirota and Bifidobacte rium adolescentis at 37 degrees C for 8 h keeping a 1:1.5 proportion betwee n the lactic and bifidobacteria within a 5% (v/v) inoculum size. The fermen ted beverage was lightly extra-flavoured with vanilla essence and subjected to chemical, microbiological and sensory evaluations during storage for 28 days at 4 degrees C. Except a slight variation in the acidity, no other pr operties changed even after 28 days. There were no contaminating organisms (Salmonella and coliforms), which indicated the sanitary and hygienic condi tions of the processing and the viable cells of the bacterial strains was w ell within recommended limits (6.8 x 10(8) cells for L. casei and 2.3 x 10( 7) cells for Bifidobacterium). No negative changes were found in the sensor y characteristics of the beverage allowing its good acceptability in all du ring the storage period.