Development and Evaluation of a Non-Dairy Probiotic Beverage from Brown Rice (Oryza sativia)

Abstract

The development of functional foods to promote health is currently of global relevance. Prebiotics are food ingredients that exert beneficial health effects on the host by stimulating the growth of probiotics. This work examined the potential of brown rice in the production of probiotic beverage (PB) inoculated with Lactobacillus acidophilus and Streptococcus thermophillus. The beverage quality and probiotic viability were evaluated over 4 weeks storage and compared with a control beverage (CB) which was produced without inoculation. The physicochemical analyzes result showed viscosity of PB (601-1200 cp) to be higher than CB (500-550 cp). The specific gravity of PB (0.99-1.90) was not significantly different from CB (1.00-1.92). The % Brix increased more in PB (6.10-7.00) than in CB (4.90-6.50). There was more reduction in pH in a probiotic beverage (5.32-4.77) than in the control (6.21-5.96). The total microbial count at the end of fermentation ranged from 3.3 × 108 to 4.1 × 109 CFU/ml for PB and 1.0 × 101 to 3.3 × 103 CFU/ml for the control sample CB. There were no detectable fungi and coliform growths in the probiotic sample (PB). However, a range of 1.1 × 101 to 4.2 × 103 CFU/ml fungi and <1.0 × 101 CFU/ml coliforms were observed in the control (CB). Lactobacillus acidophilus (5.0 × 106 to 2.9 × 107) CFU/ml proliferated more compared to Streptococcus thermophillus (2.0 × 105 to 3.2 × 106) CFU/ml in the probiotic sample (PB) but lagged in the control sample (CB). The beverages differed significantly (p ≥ 0.05) with respect to overall sensory acceptability. The inoculated beverage (PB) showed better acceptance than the non-fermented beverage (CB). At the end of 4 weeks of evaluation, the inoculated brown rice beverage was able to support high probiotic cell viability which confirms its prebiotic potential.