ASSESSMENT OF PROBIOTIC PROPERTIES OF LACTOBACILLI ISOLATEDFROM NIGERIAN SOFT CHEESE (WARA) AND ITS SURVIVALPATTERNIN SOYMILK

Abstract

Fresh cheese (wara) samples were obtained from different sources in Akure metropolis, Ondo State, Nigeria. The samples were subjected to microbiological analyses. Microbial isolates from the samples were identified and characterized based on their morphological and biochemical properties. The presumptive Lactobacillus species were then subjected to more sugar fermentation to ascertain their identity to species level. The microbial isolates were subjected to probiotic characterization based on their tolerance to salt (1-9%), bile (0.05-0.5), pH (2.50-7.50), and temperatures (15, 40 and 45oC). They were also subjected to both antibacterial and antibiotic susceptibility tests. Lactobacillus plantarum was found to have the best probiotic property. Soya milk was prepared in the laboratory using standard methods. The prepared soymilk was then divided into three portions and each portion was inoculated with the isolate (Lactobacillus plantarum) that had the best probiotic characteristics. The inoculated portions were stored at three different temperatures (5±1oC, 28±2oC and 37oC) for fourteen days. The survival pattern of the Lactobacillus plantarum and proximate analysis of the stored soymilk was carried out. Lactobacillus plantarum was seen to maintain stable growth of optical density 2.30 at refrigerated temperature, from the 3rd to the 14th day of exposure. Lactobacillus plantarum had the best probiotic property and survived for a longer period when stored at refrigerated temperature. This study reveals that probiotic milk could be produced from a non-dairy source such as soymilk