THESE UNIQUE El Hassane Kéhien-Piho TOU - Nutridev

International Journal of Food Microbiology 106 (2006) 52 – 60
www.elsevier.com/locate/ijfoodmicro
Study through surveys and fermentation kinetics of the traditional
processing of pearl millet (Pennisetum glaucum) into ben-saalga,
a fermented gruel from Burkina Faso
E.H. Tou a,b , J.P. Guyot b, *, C. Mouquet-Rivier b , I. Rochette b , E. Counil b , A.S. Traoré a ,S.Trèche b
a Université de Ouagadougou/UFR-SVT/CRSBAN, Burkina Faso
b UR106, ?Nutrition, Alimentation, SociétésX, Institut de Recherche pour le Développement (IRD), BP 64501, 34394 Montpellier, France
Received 23 June 2004; received in revised form 19 February 2005; accepted 21 May 2005
Abstract
Traditional cereal-based fermented foods are frequently used as complementary foods for infants and young children in Africa. This is the case
for ben-saalga, a popular fermented gruel produced from pearl millet (Pennisetum glaucum) in Burkina Faso. Detailed knowledge of traditional
processing is a prerequisite for investigating ways to improve both the nutritional and sanitary qualities of the corresponding foodstuff. In this
work, the traditional processing of pearl millet into ben-saalga was investigated in 24 production units, and fermentation kinetics were studied in
pilot scale experiments. Processing steps include: washing (optional), soaking of the grains (first fermentation step), grinding and sieving of the
wet flour, settling (second fermentation step), and cooking. The soaking step was mainly characterized by alcoholic fermentation whereas lactic
acid fermentation occurred during the settling step. Fermentation kinetics during settling indicates a temporal variation of metabolic activity.
Initially, both homofermentative and heterofermentative pathways were simultaneously active, and later only a homofermentative pathway was
active. The paste produced at the end of settling had a low pH (4.0T0.4) and its microflora was dominated by lactic acid bacteria (LAB) with an
amylolytic LAB/LAB ratio of 12%. Sucrose disappeared in the grains during soaking but was not detected in the soaking water, whereas glucose,
fructose and maltose appeared transiently. Glucose and fructose were the main substrates observed for lactic acid fermentation during the settling
step; however unbalanced fermentation led to the hypothesis that starch hydrolysis products may also serve as substrates for lactic acid formation.
At the end of the processing, a 75% and 83% decrease was observed in phytate (IP6) and raffinose, respectively. The sour gruel ben-saalga
resulting from cooking the sour paste had inadequate nutritional characteristics with respect to infants’ and young children’s requirements; it was
characterized by fluid consistency (Bostwick flow: 137 mm/30 s) and low energy density (about 30 kcal/100 g of gruel).
D 2005 Elsevier B.V. All rights reserved.
Keywords: Lactic acid fermentation; Pearl millet; Complementary food; Phytate; a-Galactoside; Amylolytic lactic acid bacteria
1. Introduction
* Corresponding author.
E-mail address: jpguyot@mpl.ird.fr (J.P. Guyot).
Throughout Africa, fermentation is a traditional part of
cereal and cassava processing. A wide range of cereal-based
fermented foods exists (Tomkins et al., 1988; Hounhouigan et
al., 1991; Oyewole, 1997; Blandino et al., 2003) such as ogi
and mawè in Benin, kenkey in Ghana, injera in Ethiopia, potopoto
in Congo, ogi and kwunu-zaki in Nigeria, uji and togwa
in Tanzania, kisra in Sudan. These foods are still often used to
prepare gruels for the complementary feeding of infants and
young children. However, compared to the required composition
of complementary food (Dewey and Brown, 2003; Lutter
and Dewey, 2003), the traditional gruels have low energy and
nutrient density (Lorri and Svanberg, 1994; Trèche and
Mbome, 1999) and traditional methods of processing need to
be changed to improve the quality of these foods.
A great deal of information about processing (Kitabatake et
al., 2003; Blandino et al., 2003), biochemical (Hounhouigan et
al., 1993; Kingamkono et al., 1994; Svanberg and Lorri, 1997)
and microbiological characteristics (Odunfa and Adeyele,
1985; Nout et al., 1989; Mensah et al., 1991; Lei and Jakobsen,
2004) is available on numerous traditional cassava and cerealbased
fermented foods. However, only a few studies, like those
on Ghanaian koko (Lei and Jakobsen, 2004) and on togwa
(Kitabatake et al., 2003), are based on descriptions made from
0168-1605/$ - see front matter D 2005 Elsevier B.V. All rights reserved.
doi:10.1016/j.ijfoodmicro.2005.05.010