Eliud Nalianya Wafula, Charles M.A.P. Franz, Sascha Rohn, Melanie Huch, Julius Maina Mathara, Bernhard Trierweiler
Fermentation is one of the oldest food processing technologies known to mankind. In developing countries, where refrigeration is not common, the fermentation process is widely used and of crucial importance for prolonging the shelf-life of food. The fermentation techniques used in Africa are often applied on a small scale and household basis, characterized by the use of simple and non-sterile equipment, unregulated conditions, sensory fluctuations, poor durability and unattractive packaging of the processed products, resulting in foods of unpredictable quality. Research studies have shown that there is limited information on leafy vegetable fermentation in Africa, unlike traditional fermentations based on other raw materials such as animal or plant protein, or starchy plant substrates. The major lactic acid bacteria associated with fermented plant products includes Lactobacillus plantarum, Lactobacillus fermentum, Leuconostoc mesenteroides, Lactobacillus acidophilus and Lactococcus lactis strains. Food fermentation is an important food processing technology, since it increases the shelf-life, safety, palatability and sensory quality of the raw product, reduces undesired and toxic compounds, and may increase the availability of proteins and vitamins. Furthermore, some Lactic Acid Bacteria strains are well-known probiotics and it has been postulated that lactic fermented foods may also have positive effects on human gastrointestinal health. Thus, Lactic Acid Bacteria fermentation is not only of a major economic importance, but may also promote human health in Africa. So far, the fermentation of leafy vegetables has not been practiced widely in Africa, even though these food products suffer from high post-harvest losses. The purpose of this review is to assemble current knowledge on fermentation of African indigenous leafy vegetables and to evaluate possible avenues for development of specific African leafy vegetable fermentations.
African indigenous leafy vegetables, fermentation, lactic acid bacteria, safety, quality