The Effect of Fermentation and Storage Temperature on the Viability of Lactiplantibacillus plantarum subps. plantarum Dad-13 on Yogurt-Like Drink

This study aims to assess the viability of the cell population during the fermentation process and storage at various temperatures. Probiotic bacteria, Lactiplantibacillus plantarum subsp. plantarum Dad-13, procured from the Center for Food and Nutrition Studies UGM, was utilized as a starter in manufacturing a yogurt-like drink. During the manufacture of the yogurt-like drink, cell counts were evaluated prior to and following a 12-hour fermentation period at temperatures of 30 ℃, 37 ℃, and 42 °C. The samples that have the highest viability cell (30 °C) were selected for further study and stored for 25 days at 26 °C, and for 50 days at 10 °C and 4 °C. The cell count was assessed every 5 days using MRS Media.The result indicates that fermenting at 42 °C led to a notably lower cell growth rate of 0.2 log cycles compared to fermenting at 30 °C and 37 °C, leading to cell growth of 1.37 and 1.31 log cycles, respectively. The viability of Lactiplantibacillus plantarum subsp. plantarum Dad-13 in a yogurt-like drink was not significantly different after being stored for 50 days at temperatures of 10 °C and 4 °C. The decline in cell counts of Lactiplantibacillus plantarum subsp. plantarum Dad-13 in samples stored at 10 °C and 4 °C was 0.65 and 0.34 log cycles, respectively. Conversely, at 26 °C, the viability decreased significantly, resulting in a reduction in number of 2.05 log cycles.