Bacillus Species Consortium as a New Starter in the Optimization of Cassava Tuber Retting

Abstract

This work aims to contribute to the elaboration of a stater consortium of performing <i>Bacillus</i> Spp capable of significantly standardizing the retting of cassava tubers. We monitored the retting, and the changes in multiple parameters, including pH, titrable acidity, bacterial level, texture profiles, volatile flavor compounds, and sensory quality. We proceeded with the isolation of bacteria of the genus <i>Bacillus</i> which were further characterized by classical microbiology techniques. In total, fifty-seven bacteria were obtained. Some of them were confirmed by FibE multiplex PCR. The identified organisms belonged to three <i>Bacillus</i> species: <i>B. subtilis</i>, <i>B. pumilus</i>, and <i>B. safensis</i>. Based on the Penetrometry Indices after 24, 48 and 72 hours (PI48) and enzymatic profiles, 24.5% (14) from Mokiki presented interesting fermentation potential, these were selected to realize seventy-seven <i>Bacillus</i> spp consortia in duo. 12% could easily soften cassava tubers after 24 and 48 hours (PI24≥6 and PI48≥8). These consortia allowed the retting of cassava with a shorter fermentation time of two days. <i>Bacillus</i> constituting the consortia also showed the ability to produce a range of biomolecules potentially involved in their fermentative capacity including Pectinase, Amylase, Protease and Biosurfactant.