Development of functional symbiotic beverages enriched with pomegranate peel for enhanced health and sustainability

Nowadays, companies are increasingly seeking functional foods providing health benefits to consumers, while supporting environmental sustainability. In this context, novel beverages were formulated by mixing apple juice/pulp with different plant-based drinks, i.e. oat, spelt, or soy, or whole milk. Formulations were supplemented with probiotic bacteria (Lactiplantibacillus plantarum DSM 25710 and Bifidobacterium lactis BB12, inoculated alone or in combination), along with pomegranate peel (PP), a by-product rich in tannins with antioxidant, antimicrobial, and gut health-promoting properties. To assess the effects of both the PP and microbial strains - alone and in synergy - cell viability, total phenolic content, antioxidant capacity, and volatile compound profiles were monitored over 40 days at 4°C. Results indicated that L. plantarum maintained high viability throughout the storage period, regardless the presence of PP or the type of beverage. Conversely, B. lactis showed a marked reduction in viability after 20 days, enhanced by the presence of PP. Notably, co-culturing the strains improved B. lactis survival until the end of the storage, being the viability of both the probiotics improved in the presence of PP. Additionally, PP inclusion resulted in a threefold increase in phenolic content and a tenfold boost in antioxidant activity. Finally, beverages containing L. plantarum displayed a diversified and distinct volatile profile, suggesting a greater metabolic activity. This work is funded under the National Recovery and Resilience Plan Mission 4 Component 2 Investment 1.3 - Call for tender No.341 of 15 March 2022 of Italian Ministry of University and Research funded by the European Union – NextGenerationEU; Project code PE00000003, Concession Decree No.1550 of 11 October 2022 adopted by the Italian Ministry of University and Research, CUP D93C22000890001, Project title “ON Foods - Research and innovation network on food and nutrition Sustainability, Safety and Security – Working ON Foods”.