Utilization of <i>Lactobacillus rhamnosus</i> as probiotic adjunct culture for the development of tempeh

Abstract

In this study, tempeh was developed using a probiotic culture of Lactobacillus rhamnosus adjunct culture. Purposely, soybean seeds were soaked overnight at room temperature and then boiled at 100°C for 10 to 15 min. The hot beans were then spread out in a thin layer and allowed to cool to room temperature. The Lactobacillus rhamnosus culture was added to the soybeans, which were then tightly packed in perforated plastic bags and incubated at 30°C for 24 h to produce fresh tempeh. The tempeh was then analyzed for its physical, chemical, microbial, and sensory characteristics, and the data obtained was statistically analyzed. The results of the physical and chemical analysis showed that the probiotic tempeh had a slight increase in pH, ash, and protein content, while there was a significant decrease in acidity, moisture, and fat content during storage. The microbial analysis revealed that both the total plate count and probiotic count increased over time, with treatment T4, which contained a high amount of culture, exhibiting the maximum plate count and probiotic count. The sensory evaluation showed that both the treatment and storage duration significantly impacted the aroma, color, taste, and overall acceptability of the tempeh, with all sensory attributes decreasing over time. The sensory panelists rated treatment T4 the highest for overall acceptance. In conclusion, the study suggests that probiotic soybean tempeh could be a beneficial carrier for producing a product with good physicochemical properties, acceptability, high probiotic viability, and storage durability.