Investigation of the possibility of fermentation of stage 7 ripeness bananas (Musa acuminata AAA var. Cavendish) by Lactiplantibacillus plantarum and Lacticaseibacillus casei

Abstract

This study aimed to evaluate the lactic acid fermentation potential of stage 7 ripeness banana juice, a maturity level generally less preferred for fresh consumption due to its heavily spotted peel and softening flesh. Three starter cultures, including Lactiplantibacillus plantarum, Lacticaseibacillus casei, and a 1:1 mixture of both strains, were used in this study. Banana juice was subjected to enzymatic treatment and browning inhibition with green tea extract and was subsequently fermented at 37°C for 18 hours. Results of physicochemical analysis before and after fermentation showed that all three cultures were able to grow and ferment effectively in the banana juice-green tea extract medium. Among them, L. plantarum performed best, followed by the mixed culture, then L. casei, as indicated by higher OD₆₀₀ values and greater reductions in pH and °Brix values. After fermentation, viscosity decreased and colour improved across all samples. Consumer acceptability scores ranged from 6 to 7 out of 9, indicating slight to moderate acceptance. These results suggest that stage 7 bananas are a promising material for lactic acid-fermented beverage development, contributing to increasing the value of agricultural products and minimising post-harvest losses.