African Journal of
Microbiology Research

  • Abbreviation: Afr. J. Microbiol. Res.
  • Language: English
  • ISSN: 1996-0808
  • DOI: 10.5897/AJMR
  • Start Year: 2007
  • Published Articles: 5232

Full Length Research Paper

Diversity of yeasts involved in the fermentation of tchoukoutou, an opaque sorghum beer from Benin

A. P. P. Kayodé1*, G. Vieira-Dalodé1, S. O. Kotchoni2, A. R. Linnemann3, J. D. Hounhouigan1, M. A. J. S. van Boekel3 and M. J. R. Nout4 
1Département de Nutrition et Sciences Alimentaires, Faculté des Sciences Agronomiques, Université d’Abomey-Calavi, 01 BP 526 Cotonou, Bénin. 2Product Design and Quality Management group, Wageningen University, P.O. Box 8129, 6700 EV Wageningen, The Netherlands. 3Department of Biology, Rutgers University, Camden, New Jersey 08102, USA. 4Laboratory of Food Microbiology, Department of Agrotechnology and Food Sciences, Wageningen University, P. O. Box 8129, 6700 EV Wageningen, The Netherlands.
Email: [email protected]

  •  Accepted: 30 July 2011
  •  Published: 16 September 2011

Abstract

Opaque sorghum beers are traditional alcoholic beverages in several African countries. Known as tchoukoutou in Benin, the beer is often obtained from an uncontrolled fermentation. It is consumed in an actively fermenting state and has a sour taste. The present study characterized and identified the yeasts involved in the fermentation process of this type of beer using the phenotypical approach. Of 12 beers from 4 different locations, the mean values of the pH, titratable acidity, dry matter content and refractive index were respectively 3.67, 0.70 (% as lactic acid) 18.08% and 7.00. Lactic acid bacteria and yeasts were the predominant microorganisms involved in the fermentation of tchoukoutou. Their counts were respectively 9.1 log cfu/ml and 9.1 logcfu/g. Enterobacteriaceae were not detectable in the beer. Based on the phenotypic characters and the assimilation profiles of 40 isolated yeasts, four genera with seven species of yeasts were identified. The yeast species predominant in the Benin opaque sorghum beer tchoukoutou was Saccharomyces cerevisae.

 

Key words: Sorghum, beer, tchoukoutou, Saccharomyces cerevisae, yeast.