Physicochemical and microbial community dynamics of Kocho fermented from different enset varieties in South West Ethiopia

Abstract

Enset (Ensete ventricosum (Welw.) Cheesman) is an indigenous multipurpose plant in Ethiopia. More than 20 % of people in Ethiopia rely on enset for their subsistence livelihood. Its fermentation produces a starchy food named Kocho, which is yet poorly studied. In this study, physicochemical and microbial community dynamics of Kocho fermented from different enset varieties (Maziya, Genna, and Arkiya) were collected at Dawro Zone (Southern Ethiopia). Samples were collected at various fermentation times (days 1–60) for physicochemical and microbial (culture-dependent and culture-independent) characterization. Results showed that increasing fermentation time has a significantly strong positive (R2 = 0.768, p = 0.004) correlation between titrable acidity, and a significantly strong negative association with pH (R2 = −0.715, p = 0.009), moisture (R2 = −0.982, p < 0.05), ash (R2 = −0.932, p < 0.05), fat (R2 = −0.861, p < 0.05), fiber (R2 = −0.981, p < 0.05) and carbohydrate (R2 = −0.994, p < 0.001) contents. An increasing or decreasing trend of physicochemical parameters observed during enset fermentation is significantly associated with microbial community dynamics. Shifts of microbial community observed during culture-dependent analysis were also confirmed by metagenomic results. During fermentation, Firmicutes (39–68 %) > Proteobacteria (7–53 %) > Cyanobacteria (7–24 %) were dominant phyla in the three enset varieties. Gamma (traditional starter culture) is dominated by Lactobacillus plantrum and Lactobacillus manihotivorans most probably the two species that play a significant role in initiating enset fermentation.