LAUSR

Abstract The aim of this study was to evaluate the effect of the microencapsulation (by spray drying) of the whey-native probiotic yeast Kluyveromyces marxianus VM004 in matrices of whey protein concentrate (WPC) and water-soluble chitosan (WSCh) on the viability of the yeast during drying and storage and in simulated gastrointestinal conditions. The optimized outlet drying temperature was 68 °C. This temperature allowed obtaining an encapsulation efficiency of 91% for a suspension of 10% (w/v) WPC. Yeasts microencapsulated in WSCh showed a significantly improved tolerance to simulated gastrointestinal conditions in comparison to free yeasts and yeasts microencapsulated in WPC. Besides, the solids content showed a significant influence on the probiotic viability during storage, with a suspension with 30% (w/v) solids (29:1 WPC:WSCh) showing 95% of viability after passing through gastrointestinal conditions. The results allow expanding the development of mixtures of encapsulating materials to improve the probiotic aptitude of a food ingredient powder.