Investigation of the prebiotic potential of rice varieties for Lactobacillus acidophilus bacteria

Abstract

This study investigated the interaction of rice flour and two local strains of Lactobacillus acidophilus bacteria (LAB) from Kyrgyzstan used for the modification of a functional product for infant nutrition. White rice 2% w/w and a local variety of brown rice 2% w/w were used as prebiotic ingredients. The fermentation time of the samples ranged from 257 to 270 min to reduce the pH from 6.5 to 4.6. In the control product with 4% (w/w) sugar the fermentation was faster (257 min), however, gel setting G′/G″, measured with oscillation rheology, occurred at least after 182 min. Gel formation of the white rice-enriched samples was detected at 116 min and for brown rice-enriched samples at 168 min. The average pH of the samples at the end of 7 days of storage was in the following range: for control sample 4.68; for brown rice—4.29; for white rice—4.18. Within 7 days of storage, the viability of LAB in all samples remains high 87.71–95.40%. Additionally, supplementation with 2% white and brown rice reduced syneresis, i.e. increased the water-holding capacity, viscosity, gel strength, and sensory properties of the end product. Newly developed food with probiotic and prebiotic ingredients, regarding low sugar content, low acidity, and suitable consistency, was recommended for infant nutrition on the first 2 days of production.