Abstract:
The potential of different types of prebiotics which are inulin, gum arabic (GA), fructooligosaccharide (FOS) and isomaltooligosaccharide (IMO) to enhance the growth of lactic acid bacteria (LAB) in fermented guava drink being investigated. Three LAB strains, Lactobacillus acidophilus, Lactobacillus bulgaricus and Lactobacillus casei were used in this study. The guava drinks prepared from guava, sugar and water, supplemented with 1% (v/v) probiotic and 6% (w/v) of different prebiotics each been fermented for 72 hour at 30oC in anaerobic condition. The fermented drink were then stored at 4oC for 14 days. Total viable count, pH, lactic acid content and degree Brix were determined. Sensory evaluation was performed involving 30 panelists to determine on consumer’s acceptability of prebiotic drink. It was found that gum arabic shows better microbial growth among all prebiotics with 7.58 ± 0.04 log10 cfu/ml while the lowest microbial population shows by FOS with 7.37 ± 0.23 log10 cfu/ml. The increase in LAB growth will lead to increase in lactic acid content which shows gum arabic increased of its titratable acidity from 0.05% to 0.19%. pH of all fermented drinks were decreasing in the range of 5.05 to 3.40 and IMO shows the higher reduction of pH from 4.72 to 3.94. Gum arabic shows higher total soluble solids with 16.4 oBrix which decreased to 13.15 oBrix. For the overall acceptance, the highest mean value is 5.13 obtained from guava drink supplemented with 6% (w/v) IMO. Results of this study indicated that the probiotics were capable in of growing well in sterilized guava drink supplemented with 6% (w/v) gum arabic and have a potential use as a prebiotic health food.
