Stability of health-promoting compounds added to banana (Musa × paradisiaca) slices by impregnation with LAB-fermented solutions

Abstract This study aimed to develop stable dried banana slices impregnated with a lactic acid bacteria (LAB)-fermented solution containing soy isolate, prebiotics, and pomegranate extract antioxidants. Soy isolate-based solutions mixed with pomegranate extract, mucilage from flaxseed, and/or inulin were fermented with a cocktail of four lactic acid bacteria ( Lactobacillus acidophilus , Lacticaseibacillus casei , Limosilactobacillus reuteri , and Lacticaseibacillus rhamnosus ) to be used as a medium to impregnate banana slices. The impregnated banana slices were then air-dried (40 °C), and their physicochemical characteristics, health-promoting compounds, and sensory acceptance were evaluated at the beginning and after 60 days of storage at 20 ± 3 °C. In general, the results indicated that the physicochemical characteristics, total phenolic compounds, and total flavonoids of impregnated banana slices remained unchanged; however, the antioxidant capacity of impregnated banana slices increased with the addition of soy isolate (36.33%) and pomegranate extract (45.85–74.71%) in the fermented solutions. In addition, all banana slices impregnated with fermented solutions showed probiotic counts in the range of 6.84–8.00 logs (6.83–100.00 million CFU/g) at the beginning of storage. Nevertheless, at the end of storage, only the system containing all health-promoting compounds showed a probiotic count above 6.87 log (7.35 million CFU/g); these banana slices also showed the highest antioxidant capacity, without affecting their sensory acceptance ( p < 0.05). Although “in vivo” studies should be conducted, this research developed a functional food with antioxidant, prebiotic, and probiotic characteristics that remained stable for 60 days during storage outside the cold chain.