THESE UNIQUE El Hassane Kéhien-Piho TOU - Nutridev

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profiles by API 50 CHL strips and metabolic
type. The metabolic type of strains was
determined by analysis of the acetic and
lactic acids, and ethanol in the fermentation
broth by High Performance Liquid
Chromatography (HPLC). The phenotypic
identification of LAB was carried out by API
50 CHL biochemical tests (BioMérieux,
France). The results of the identification tests
were interpreted using the APILAB PLUS
software (BioMérieux). The taxonomic
classification of the isolates was based on a
binary matrix established from the presence
or absence of phenotypic characters. The
binary matrix was translated into a matrix of
distances using the coefficient of dissimilarity
of Nei and Li. Based on this matrix, a
dendrogram was established by using the
algorithm UPGMA (Unweighted Pair Group
Method with Arithmetic mean).
3. Results and discussions
3.1. Lactic acid bacteria counts
Counts of lactic acid bacteria (LAB) were
performed in samples of fermented pastes
obtained from 12 producing units. LAB
counts varied between 7.5 and
8.5 logCFU/ml, and they were similar to
those observed in boza, Bulgarian cerealbased
fermented beverage (Gotcheva et al,
2000). However, LAB counts seem rather
low in comparison to those of other
traditional fermented cereals (Mugula et al,
2003). That could be attributed to the low dry
matter content of ben-saalga fermented
pastes which were much diluted and resulting
therefore in a low availability of substrate for
microbial growth. LAB represented the
dominant microflora, similarly to results from
several studies carried out on the
microorganisms involved in cereal-based
fermented foods (Aguirre and Colins, 1993;
Caplice and Fitzgerald, 1999; Gotcheva et al,
2000; Lei and Jakobsen, 2004). LAB
dominance is consistent with the fermentation
kinetics during the settling step (Tou et al,
2006).
3.2. Phenotypic characteristics of bacterial
strains
184 bacteria were randomly isolated from
fermented pastes sampled in 12 producing
units and they were purified and
characterised. For each isolate being Gram
positive and catalase negative (presumptively
LAB), their fermentation profile was
determined using API 50 CHL galleries and
their end-products from glucose fermentation
were determined by HPLC to determine their
fermentative pathway. The results are shown
in table1.
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