The Effects of Mandillo (Crassocephalum Macropappum) on the Physico-chemical Profile and Microbial Dynamics during Enset (Ensete Ventricosum Welw.) Fermentation

Fermentation of Enset has been known for a long time to produce a starchy and nutritionally enriched food product referred as Kocho . However, due to uncommon sensory attributes for non-Enset consuming societies, a short shelf life and a long fermentation period, Kocho has been ignored worldwide and limited to only some regions of Ethiopia. To improve its sensory attributes and enhance its fermentation rate, Shekacho society in Ethiopia uses the stem of Mandillo as a starter culture ingredient. Therefore, this study was initiated to determine the effects of Mandillo ( Crassocephalum macropappum ) on the microbial dynamics and physicochemical properties of Enset ( Ensete Ventricosum Welw. ) fermentation products. Microbial enumeration and isolation were carried out following standard methods on suitable culture media. Various fermentation parameters were determined analytically. Molecular identification of LAB and yeasts was based on 16S and 18S rRNA genes sequencing, respectively. In this study, significant (p<0.05) differences were observed between control (Koki) and experimental Kocho (Kom) samples. The lactic acid bacterial (LAB) count increased by 23.3 folds on day 37 of fermentation of Enset with Mandillo . Similarly, the yeast count increased by 2.6 folds on day 29 of the fermentation period. On the final (45 day), lactic acid and acetic acid contents increased by 103.90% and 40.04%, respectively whose cumulative effect resulted in a lowering of pH by 0.65. The titratable acidity increased by 64.34%. The 16S rRNA gene sequence analysis assigned LAB to Lactobacillus spp. Accordingly, 82.14% strains identified as Lactobacillus , 9.82%isolates identified as Leuconostoc , and 8.04% isolates reported unidentified LAB strains in Kocho . Similarly, the major yeast strains were molecularly characterized as Candida boidinii (26%), Wickerhamomyces sp. UFLA (16%), Candida sp. MM 4018 (8%), but some yeast strains (28%) remained also an unidentified. The current findings revealed that Mandillo exhibited significant effect on the microbial dynamics of Enset fermentation with overall improvement of the final product.