The effect of the addition of Bifidobacterium BB-12 microencapsulated by spray drying with sweet whey and inulin on the microbiological, physicochemical and texture properties of Greek-style yogurt was evaluated during 28 days of storage. The survival of this probiotic under simulated gastrointestinal conditions was assessed after this storage time. Three formulations of Greek-style yogurt were produced: Control (with free cells); SW (with microcapsules produced only with sweet whey); and SWI (with microcapsules produced with sweet whey and inulin). The counts of Bifidobacterium BB-12 remained stable during storage in the Control yogurt and in the SW yogurt, while a slight decrease occurred in the SWI yogurt. Nevertheless, the addition of microcapsules improved the survival of S. thermophilus and L. bulgaricus in the SW yogurt after 14 days of storage. In general, incorporation of microcapsules into Greek-style yogurt affected specific physicochemical and textural properties of the samples. A decrease in the probiotic survival rate during gastrointestinal simulation was observed for all samples; however, it was more pronounced in the SWI yogurt. Even though the protective effect of the microcapsules was not evident, the results showed that Greek-style yogurt is a promising carrier for incorporation of Bifidobacterium BB-12.
Keywords: In vitro simulated gastrointestinal; Microencapsulation; Prebiotic; Probiotic yogurt; Whey.