Quality of fermented goat milk and powder milk using Lactobacillus plantarum and optimizing their antibacterial ability against enterobacteriaceae

Abstract

The purpose of the study was to evaluate the quality of fermented goat milk using Lactobacillus plantarum and determine its antibacterial ability against enterobactericeae. The quality of fermented milk was evaluated through measurement of pH, lactic acid levels, protein content and total bacteria. The antibacterial ability was measured by inhibitory tests on enterobactericeae. The experiment was applied in a completely randomized factorial design with two factors, namely factor A, type of milk (goat’s milk and powder milk), factor B, level of Lactobacillus plantarum (2.5, 5 and 7.5%) and 3 equal replicates. The data were subjected to analysis of variance, and continued to Duncan’s multiple range test to determine the difference between means at 1 % probability. The results indicated that milk type and L. plantarum levels had a very significant effect on pH, lactic acid levels, and the inhibitory zone width. There is an interaction between factors. Meanwhile the type of milk had very significant effects (P <0.01) on protein content and total lactic acid bacteria. In conclusion, fermented goat milk has better quality and antimicrobial ability against enterobactericeae than powder milk.