Enhancing probiotic survival and quality of fermented goat milk beverages with bael (Aegle marmelos) fruit pulp

Abstract

This study aimed to assess the impact of bael fruit pulp on the viability of probiotic Lacticaseibacillus rhamnosus GG (LGG) and some physicochemical properties of bael-goat milk-based beverages during 21 days of refrigerated storage. Bael fruit pulp (BFP) was incorporated into goat milk (GM) at different levels (0 %, 5 %, 10 %, and 20 %), and fermented with LGG combined with conventional yoghurt culture. Products were analyzed at weekly intervals. Fermented GM without bael served as control. Redness (a*), yellowness (b*), chroma, and LGG viability were all significantly increased while pH, lightness (L*), and whiteness were dramatically decreased by the addition of BFP. After 14 days of storage, all fermented milk containing bael exhibited considerably (p < 0.05) greater LGG counts than the control. The product containing 20 % bael had the greatest viability counts (7.01 log CFU/mL) at the end of storage. Throughout the storage period, all of the products—including the control—maintained viable probiotic counts of greater than 6 log CFU/mL. The pH of the products decreased over time but was stabilized by bael. In conclusion, the findings demonstrate that goat milk is a perfect vehicle for LGG, and adding bael may boost the fermented goat milk's probiotic viability, physicochemical qualities, and nutritional value, thus improving its overall quality.

Keywords

• Functional beverage
• Lactic acid fermentation
• Lacticaseibacillus rhamnosus
• Milk-fruit beverage
• Viability