Viability of microencapsulated Lactobacillus acidophilus by complex coacervation associated with enzymatic crosslinking under application in different fruit juices

Abstract

The objective of this study was to produce microcapsules containing Lactobacillus acidophilus LA-02 by complex coacervation followed by crosslinking with transglutaminase and to evaluate the effect of their addition on different fruit juices, as well as the probiotic viability of L. acidophilus and its effect on fruit juices during storage. To this end, L. acidophilus was microencapsulated by complex coacervation, followed by crosslinking with transglutaminase at different concentrations. Probiotics, in their free and microencapsulated forms, were added to orange juice and apple juice at concentrations of 10% and 30%. The obtained microcapsules were characterized in terms of morphology. The viability of probiotics and the effects of their addition on fruit juices were assessed and the juices characterized (with respect to pH and total soluble solids) during 63 days of storage at 4 °C. Orange juice proved to be more suitable for the addition of probiotics, and the survival of probiotics was directly related to pH. The microcapsules had a protective effect on L. acidophilus, prolonging their survival, and the crosslinking process proved to be adequate and promising, ensuring probiotic viability. Thus, the complex coacervation process associated with induced enzymatic crosslinking provided protection for L. acidophilus in different fruit juices, showing an adequate methodology for adding probiotics to this adverse food matrix, guaranteeing the survival of L. acidophilus for up to 63 days, and generating products with innovative and promising probiotic appeal.