Co-encapsulation efficiency of silk sericin-alginate-prebiotics and the effectiveness of silk sericin coating layer on the survival of probiotic Lactobacillus casei

The use of silk sericin protein as a biomaterial to co-encapsulate probiotic Lactobacillus casei TISTR 1463 with alginate and various prebiotics was determined. In addition, 0.2% silk sericin was also evaluated as a coating material to improve the viability of probiotic cells. Silk sericin coating has the potential to enhance probiotic survival in freeze-dried microcapsules. Under refrigerated storage condition of 4 °C for 120 days, alginate-silk sericin-maltitol with silk sericin coating (ASM-C) provided the best performance with the lowest inactivation rate ( k ) and the highest δ parameter (the first decimal reduction time) applied by the log-linear and Weibull models, respectively. However, the stability was relatively low at the temperature of 30 °C. Co-encapsulation of alginate-silk sericin-prebiotic and coated with silk sericin exerted a protective impact on the strain survival when exposed to high temperatures and transited through the digestive system.