Many fermented foods containing vegetable leaves are mostly consumed in the world,
particularly in Africa and Asia. These widespread foods represent the basic diet, in
addition to their raw materials available, and constitute a significant share in the food of
the local populations.
Kawal, obtained by natural and alkaline fermentation of
Senna obtusifolia
also called
Cassia obtusifolia
leaves, is a much-appreciated food and largely
consumed by the populations in Chad and Sudan.
S. obtusifolia leaves play an
important role in the food system for many communities in Africa. They are rich in
essential amino acids and can be regarded as products of nutritional interest. The
kawal
contains considerable quantities of proteins and is used as a meat substitute. It is also
rich in mineral salts and carbohydrates. The
kawal technology production remains
traditional with rudimentary equipment and an uncontrolled fermentation. However,
this fermentation, although traditional, allows the elimination of the antinutritional
factors contained in the leaves and also contributes to the improvement of the
nutritional value and the development of aromatic compounds. It also makes it possible
to increase the bioavailability of minerals and thus reduces the deficiency problems in
humans.
Bacillus
and
Lactobacillus
genus in
kawal play different beneficial roles to
humans. Indeed, the
kawal can be a source of probiotic microorganisms when the
product is consumed without a stage of cooking after fermentation, thus keeping the
probiotics alive and able to exert their beneficial effects for health. The transformation
of this product constitutes a significant stake because of the generated incomes and thus
contributes to the valorization of the forest resources and food safety. The technologies
of the transformation of
kawal not being well controlled and varying from one area to
another, in the sight of an improvement, it is necessary to make a review on
technologies of its transformation and on its nutritional value.