Effect of yellow sweet potato extract (Ipomoea batatas L.) as a prebiotic source for the kinetics of fermentation and the production of lactic acid by Lactobacillus paracasei

Abstract

This study aims to determine the effect of yellow sweet potato extract as a prebiotic source for fermentation kinetics L. paracasei. Bacteria L. paracasei, which is used here, is a collection of Laboratory Nutritional Biochemistry, Faculty of Animal Science UGM. Concentrations of yellow sweet potato extract used to determine the Km value L. paracasei were 0.01, 0.05, 0.1, and 0.2%. Lactic acid production and fermentation pH value of L. paracasei with different levels of yellow sweet potato extract (2 Km, Km, 1.5 Km) were measured after 24 hours incubation period. Km value bacteria L. paracasei obtained 2.1 g/100ml. Different concentrations of yellow sweet potato (2 Km, Km, 1.5 Km) as a treatment had a significant effect (P<0.05) on the increase in lactic acid produced and decrease in pH. Based on this experiment, it can be seen that level substrate with Km value have not produced optimal lactic acid.