Madusanki, K.S.Liyanage, R.Jayathilake, C.2022-02-152022-02-1520159789550481088http://www.erepo.lib.uwu.ac.lk/bitstream/handle/123456789/8348/31-SCT-Antioxidative%20properties%20and%20Lactobacillus%20population%20in%20.pdf?sequence=1&isAllowed=yIn recent years, probiotic products have become a primary choice for the consumers because of their health attributes (Yen-Ping Tan, 2007). Pickle may be a suitable product of carrying probiotic bacterial strains to the host. Pickling is a method of fermentation of vegetables to extend their shelf life. That process consists with the basis of reducing the pH value due to conversion of sugar to acid by lactic acid bacteria (LAB). LAB are greatly important for human health as they help balance human intestinal flora, thereby boosting overall immunity (Amit et al., 2012). Antioxidant compounds in fermented foods play an important role as a health protecting factor. Scientific evidence suggests that antioxidants reduce the risk for chronic diseases including cancer and heart disease. There is no reported study done on evaluating the nutritional properties of Sri Lankan vegetable pickles fermented with coconut vinegar. The main objective of this study was to evaluate the population growth of Lactobacillus, pH, total phenols and antioxidant activity during fermentation of Sinhala pickle. Materials and Methods Sample preparation, determination of pH and Lactobacillus population The samples for the isolation of LAB included the fermented mixed vegetables which was prepared by mixing thoroughly, cleaned and diced vegetables (carrot, red onion, raw papaya, green chili) in coconut vinegar solution, and was allowed to ferment at ambient temperature (32 C±2). The microbial spread plate method was used to isolation of LAB in the MRS media from the pickle sample. The pH of the withdrawn aliquots at every 24h during the fermentation was monitored using a digital pH meter (HI 2211, USA) at 32 C (Shori et al., 2011). Determination of Antioxidant Activity and Total Phenolic Content Antioxidant activity (AOA) was measured by DPPH radical scavenging activity method according to the method developed by Adak et al. (2013) with little modifications. Total phenol content (TPC) was measured by Folin-Ciocalteu method with some modifications (Kriengsak et al., 2006). Results and Discussion Population of Lactobacillus in pickle Traditionally, the fermentation of Sinhala pickle is processed by the LAB. The results showed that the bacteria population increased from an initial number of 8.0997 0.56 Log10 cfu/g after 24 hours fermentation at 37 ⁰C. The maximum bacteria growth was observed after 48 hours fermentation which had significant difference with other ratios of bacteria except 72 hours bacteria count. After three days storage at 37 ⁰C, the bacteria population decreased but, no significant difference was observed among other storage time. In contrast, the numbers of LAB were much reduced at the end of storage (Table 1).enScience and TechnologyTechnologyFood ScienceFood TechnologyOther