THESE UNIQUE El Hassane Kéhien-Piho TOU - Nutridev

Projet d’article
saalga (Tou et al., 2006) showed that it had a
low pH (4.0 ± 0.4), low energy density (about
30 kcal/100g of gruel). In ben-saalga
processing method, two fermentation steps
were observed. The first occurred during
soaking of the grains and the second during
the settling step. Soaking was characterised
by an alcoholic fermentation whereas, a lactic
acid fermentation occurred during settling.
Ben-saalga microbiota was dominated by
lactic acid bacteria (LAB) with an
ALAB/LAB ratio of 12% (Tou et al., 2006).
If information is available concerning the
bacteriocinogenic activity of Lactobacillus
plantarum strains isolated from ben-saalga
(Ben Omar et al, 2006), however, no general
description is available about the lactic acid
bacteria involved in the processing of bensaalga.
Information about the
microorganisms involved in indigenous foods
is essential because they specially contribute
to improve the stability and properties of
these foods.
The aim of the current work was to isolate
and characterize the lactic acid bacteria
involved in ben-saalga processing method.
Lactic acid bacteria of ben-saalga were
characterized according to their phenotypic
characteristics (morphology, Gram reaction,
catalase activity, biochemical profiles by API
50 CHL strips and metabolic type by HPLC).
2. Materials and methods
2.1. Numeration and isolation of bacterial
strains
Among a list of 93 traditional producing units
(TPU) identified during a preliminary survey
carried out in Ouagadougou (Djossou et al,
1999), 12 TPUs of fermented gruels (bensaalga
or ben-kida) have been randomly
selected. Fermented pastes were taken
aseptically in these 12 TPUs at the end of the
fermentation step. Samples were conserved at
+4°C before their analyses which were
performed the same day. Medium of de Man,
Rogosa and Sharpe (MRS, Difco) was used
to isolate lactic acid bacteria (LAB) strains
from these samples of fermented pastes.
MRS-agar was used for numeration and
isolation and MRS-broth media for routine
culture.
Strains were stored in glycerol (40%) at -
80°C. For use in biochemical tests, a 24h
culture of each strain was centrifuged
(SGMA, 4K10) at 10000 rpm for 5 min and
the pellet was washed three times in sterilised
physiological water (9 g NaCl/l).
2.2. Phenotypic characterization of bacterial
strains
The isolated strains were tested according to
their phenotypic characteristics: morphology,
Gram reaction, catalase activity, biochemical
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