Use of starter cultures of lactic acid bacteria and yeasts as inoculum enrichment for the production of gowe, a sour beverage from Benin

Lactobacillus fermentum, Weissella confusa, Kluyveromyces marxianus and Pichia anomala, previously isolated during natural fermentation of traditional gowe, were tested as inoculum enrichment for controlled fermentation of gowe. The final product was subjected to chemical analysis and sensory evaluation. Growth of the lactic acid bacteria (LAB) and yeasts were verified by determination of colony forming units (CFU) and molecular biology techniques. A significant decrease in pH from 6.1 to 3.3, with a concomitant increase in titratable acidity (11 to 60 g/kg as lactic acid, dry weight), was observed after 24 h of fermentation when LAB was used either alone or in combination with yeasts. The LAB count increased significantly from 6.1 to 9.4 log CFU/ml, while the yeast count remained constant throughout fermentation. Repetitive-polymerase chain reaction (rep-PCR) assays performed on isolates during the fermentation confirmed the dominance of the added LAB strains. Sensory evaluation revealed that the product fermented for 7 h with L. fermentum alone or in combination with K. marxianus was as acceptable as the traditional product normally obtained after a minimum of 24 h of fermentation. Consequently, gowe can be obtained by controlled fermentation, using L. fermentum as inoculum enrichment, in a small scale industry.