Sensory and Physicochemical Characterisation of Functional Yoghurts Containing Probiotic Lactobacillus rhamnosus MGRE enriched by six plants and extracts.

Abstract

Prebiotics are functional foods with health-promoting properties that are used in many health and nutrition aspects. Combined with appropriate probiotics, they produce synbiotic products with high nutritional value and health benefits. In Egypt, many traditional organic plants are reported to have prebiotic properties. In this study, the potential prebiotic effects of three different plants (Lepidium sativum, date palm pollen, and date kernel powder) and three plant extracts (Hibiscus, Hyphaene, and Hibiscus+Hyphaene 1:1) were investigated at five concentrations each (1.0, 1.5, 2.0, 2.5, and 3.0% w/w). The selected plants were used to evaluate the prebiotic properties of the probiotic bacteria L. rhamnosus MGRE. Eighteen enriched yoghurts were further used to assess the sensory and physicochemical characteristics. Some of these selected plants have a prebiotic effect. Lepidium sativum had a superior effect on bacterial growth during fermentation; ΔOD600 increased significantly from 0.10 to 1.19-1.55 (in a concentration-dependent manner), while Hibiscus negatively influenced bacterial growth compared to control. The pH of the yoghurt trials h ranged from 4.34 to 4.45, which was close to that of the control, with a difference of ± 0.11. The viscosity of the trials ranged from 1319 to 2816 mPa.S, higher than that of the control (1395 mPa.S), except for the treatment containing 2% Lepidium sativum (1319 mPa.S). The yoghurt prepared with Lepidium sativum, and Hyphaene showed the best organoleptic properties with synbiotic potential. It seems promising that Lepidium sativum, Hyphaene, and date kernel could be used as prebiotics.