Effects of the addition of microencapsulated Bifidobacterium BB-12 on the properties of frozen yogurt

Samples of frozen yogurt were added with microcapsules containing Bifidobacterium BB-12 produced with different contents of carrier agents (reconstituted skim milk and inulin). The viability of this probiotic culture was evaluated, as well as the effect of addition of microcapsules on the chemical and rheological properties of frozen yogurt during 90 days of storage. The counts of bifidobacteria maintained practically constant in the samples added with the microcapsules, while the frozen yogurt added with free bacteria showed a decrease of about 34% after 90 days. The addition of the microcapsules increased the total solids content and the overrun values. The highest pH values were noted in the samples containing microcapsules produced with reconstituted skim milk. All the melted frozen yogurts showed non-Newtonian behavior with shear thinning characteristics. The samples added with microcapsules had greater apparent viscosity and those added with microcapsules produced with inulin showed a larger hysteresis area at the end of storage period. (C) 2012 Elsevier Ltd. All rights reserved.