Traditional Spontaneously Fermented Foods and Beverages of Kenya: Biotechnological approaches, health implications, and commercial opportunities

Fermentation of food ranks as one of the oldest methods of food processing and preservation. Spontaneously fermented foods and beverages are integral to human diet in many African communities; playing an important role in contributing to the livelihoods of rural and peri-urban populations through enhanced food security and income generation via small-scale enterprises. Several traditional fermented foods and beverages are produced at household/ village level in Kenya. These include non-alcoholic cereal-based (maize/ finger millet/ sorghum) beverages such as porridges (uji and kirario), fermented milk products (kule naoto, mursik, amabere amaruranu, and suusa), alcoholic beverages from maize and/ or sorghum or millet malt (busaa, chekwe, marwa, and chibuku), fermented fruit mashes/ wine (mnazi and muratina), and distilled spirits (chan’gaa). All the fermentation processes used in the production of these products applies spontaneous inoculation, whereby the microbes associated with the raw food material and the processing environment serves as inoculants. In Kenya, most of these foods and beverages are basically similar but only the names are varied depending on the locality. Although these products have been consumed for many years as safe products, recently, some of them have been linked to deaths and adverse health effects. Some of the products are produced under unhygienic conditions and have found their way into commercial outlets however with inconsistent quality, unassured safety, and limited shelf-life. Research on the processing technologies of these foods is low and none of the products has been produced under controlled conditions using starter cultures. To develop processing technologies for these foods and contribute to food security, it is essential that the microbiology and biochemistry of the products be studied using modern molecular diagnostic techniques and their chemical composition characterized. Moreover, fermentation parameters needs to be defined and standard equipment employed to attain controlled fermentation. This article reviews the available information regarding traditional fermented foods in Kenya, challenges in developing technologies for their controlled-fermentation production, and suggests recommendations for potential research areas.