Prebiotic-alginate edible coating on fresh-cut apple as a new carrier for probiotic lactobacilli and bifidobacteria

Abstract

The increased popularity of vegetarianism, lactose intolerance, and the highcholesterol content of dairy products are all factors that have recently increased thedemand for non-dairy probiotic foods. This study aimed to evaluate the effect ofprobiotic supplementation of fresh-cut apple coated with alginate-prebiotic on itsnutritional, safety, and sensory characteristics. Also, probiotic viability duringrefrigerated storage and after simulated gastrointestinal digestion (GID) was evaluated.A new non-dairy probiotic food was developed by adding prebiotics (oligofructose andinulin) and probiotic cultures (Lactobacillus rhamnosus and Bifidobacterium animalissubsp. lactis) to fresh-cut apple. Both probiotics successfully remained above 9.0 logCFU/g in the product after 8 days of storage. Also, high viability retention was achievedafter GID with 7.8 and 8.0 log for L. rhamnosus and B. lactis, respectively, withoutsignificant effect of prebiotic addition. Microbiological and nutritional quality weremaintained, however only those samples with prebiotics and B. lactis remainedsensorially acceptable after 8 d. Furthermore, both probiotics exerted bactericidal effectagainst L. innocua inoculated on apples with reductions higher than 1.8 log meanwhile,the effect on E. coli O157:H7 was less pronounced. Thereby, apple pieces coated withprebiotic-alginate solution constitute a promising alternative to design new carriers forprobiotic bacteria.