Quantification of lactic acid bacteria and bifidobacteria in goat milk based yoghurts with added water-soluble soy extract

Abstract

This work was carried out with the objective of evaluating the microbiological aspects, during 29 days of storage, through the quantification of viable cells and probiotic bacteria enumeration, of strawberry flavored yoghurts produced with goat milk with water-soluble soy extract and Bifidobacterium animalis ssp. lactis probiotic culture during processing. Determination of the viable cell count during yoghurt storage showed that the number of lactic bacteria found was below the expected only in the treatment in which there was water-soluble soy extract addition, not presenting microbiological viability. The other yoghurt treatments were viable during storage. The enumeration of Bifidobacterium animalis ssp. lactis showed that the yoghurt treatments presented microbiological viability during storage. We concluded that the addition of water-soluble soy extract interfered negatively with the production of goat milk based yoghurts.