Diversity of lactic acid bacteria in dadih produced by either back-slopping or spontaneous fermentation from two different regions of West Sumatra, Indonesia

Abstract

Aim: Dadih samples from two different origins (Kamang and Gadut in West Sumatra) manufactured with different methods (back-slopping or spontaneous fermentation) were evaluated for the diversity of lactic acid bacteria (LAB). Materials and Methods: Four dadih samples manufactured with two different fermentation methods were obtained from Kamang and Gadut regions. Both genotypic and phenotypic characteristic (16S rRNA partial gene sequence analysis and carbohydrate fermentation profile) were used to analyze the diversity of dadih LAB population. Results: This study showed that LAB count in back-slopping fermented dadih was one log cycle higher than spontaneous fermented dadih. LAB isolates from the two regions were divided into three genera, namely Lactococcus, Lactobacillus, and Pediococcus. Sequencing results showed that 41.6% (five isolates) were identified as Lactococcus lactis ssp. lactis, 25% (three isolates) were identified as Lactobacillus plantarum ssp. plantarum, 16.6% (two isolates) were identified as L. lactis ssp. cremoris, and 8.3% (one isolate each) were identified as Pediococcus pentosaceus and Lactobacillus pentosus. Conclusion: Five species were determined in back-slopping fermented dadih, i.e., L. lactis ssp. lactis, L. lactis ssp. cremoris, L. plantarum ssp. plantarum, L. pentosus, and P. pentosaceus. On the other hand, spontaneous fermented dadih only contained three different species, namely L. lactis ssp. lactis, L. lactis ssp. cremoris, and L. plantarum ssp. plantarum. This research showed that back-slopping fermentation offers greater abundance and diversity compared to spontaneous fermentation in dadih.