Ready-to-eat blueberries as fruit-based alternative to deliver probiotic microorganisms and prebiotic compounds

Abstract

The prevalence of lactose intolerance, milk protein allergies, and the increasing vegan population have led to a growing demand for probiotic products based on non-conventional food matrices. In this study, the potential use of fresh blueberries as carriers of Lacticaseibacillus casei CECT 9104 and Bifidobacterium animalis subsp. lactis CECT 8145 incorporated into alginate-based prebiotic coatings was evaluated. Protective effect of inulin + oligofructose on probiotic viability, microbiological and sensory quality of fruits, and also, antagonistic effects of probiotics on co-inoculated E. coli O157:H7 and L. innocua were the main parameters studied along 14 days of refrigerated storage. A protective effect was observed since prebiotic enrichment allowed maintaining both L. casei and B. lactis viability above the minimum recommended levels (106 CFU/g) up to the end of storage, and therefore, ensuring their beneficial health action. Regarding safety issues, both probiotics exerted a biocontrol effect on inoculated L. innocua with reductions up to 2.31 log. Moreover, enrichment of blueberries with B. lactis through the application of prebiotic coatings maintained quality and sensory characteristics for 14 days at 5 °C. Thus, the development of functional blueberries coated with prebiotic-probiotic mixtures was achieved. These ready-to-eat fruits constitute novel, healthy and multifunctional alternatives of non-dairy probiotic foods that would allow meeting the current consumer demand.