African Journal of
Microbiology Research

  • Abbreviation: Afr. J. Microbiol. Res.
  • Language: English
  • ISSN: 1996-0808
  • DOI: 10.5897/AJMR
  • Start Year: 2007
  • Published Articles: 4881

Full Length Research Paper

Bacterial dynamics and chemical changes during the spontaneous production of the fermented porridge (Calugi) from cassava and corn

Rosane Freitas Schwan
  • Rosane Freitas Schwan
  • Biology Departament, Federal University of Lavras, 37200-000, Lavras, Minas Gerais, Brazil
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Claudia Cristina Auler do Amaral Santos
  • Claudia Cristina Auler do Amaral Santos
  • Biology Departament, Federal University of Lavras, 37200-000, Lavras, Minas Gerais, Brazil.
  • Google Scholar
Marianna Rabelo Rios Martins Santos
  • Marianna Rabelo Rios Martins Santos
  • Biology Departament, Federal University of Lavras, 37200-000, Lavras, Minas Gerais, Brazil.
  • Google Scholar
Whasley Ferreira Duarte
  • Whasley Ferreira Duarte
  • Biology Departament, Federal University of Lavras, 37200-000, Lavras, Minas Gerais, Brazil.
  • Google Scholar
Rosane Freitas Schwan
  • Rosane Freitas Schwan
  • Biology Departament, Federal University of Lavras, 37200-000, Lavras, Minas Gerais, Brazil.
  • Google Scholar


  •  Received: 01 August 2013
  •  Accepted: 24 January 2014
  •  Published: 26 February 2014

Abstract

A traditional fermented porridge made from maize, cassava and rice, named calugi, was microbiologically and chemically analyzed. Our results show that aerobic mesophilic bacteria reached values of approximately 7 log CFU ml-1 and were the predominant group; acetic acid bacteria were also observed at the onset of fermentation (3.82 log CFU ml-1). The population of lactic acid bacteria was 3.7 log CFU ml-1 and remained constant throughout the fermentation. The denaturing gradient gel electrophoresis (DGGE) bands were identified as Corynebacterium variabile, Lactobacillus paracasei, L. plantarum, L. casei, Bacillus spp. (Bacillus cereus group), B. subtilis, Streptomyces sp., Enterobacter cloacae, Streptococcus parasanguis, Streptococcus salivarius, Weissella cibaria and Weissella confusa, in addition to uncultivable bacteria. The most abundant carbohydrate in the substrate was maltose (38 g L-1 at the beginning of fermentation). Acetic and lactic acids were the principal acids found by high performance liquid chromatography (HPLC) (0.66 g L-1 and 3.54 g L-1, respectively). Twenty-one (21) minor compounds were identified by gas chromatography during the fermentation process. The compounds present at the highest concentrations were furfuryl alcohol, nonanoic acid, decanoic acid and 1,1-dietoxyethane. These appeared to be related to the flavor of the calugi.

 

Key words: Indigenous food, cereal fermentation, cassava, corn, volatile compounds, denaturing gradient gel electrophoresis (DGGE), saliva.