Flavouring composition prepared by fermentation with Bacillus spp

Fermented foodstuffs and condiments remain a key constituents of diets throughout many parts of Asia and Africa. In cases where the process of fermentation evolved for the development of taste or aroma, it often resulted in enhanced nutrition, stabilisation of the original raw materials, and detoxification of anti-nutrient factors. Several fermented products rely on the participation of various Bacillus species, including Bacillus natto and B. subtilis. Often, the finished products are of a very local character and exhibit sensory properties resulting from unique flora and processing technologies applied in small scale, home-based fermentations. Fermentation with B. natto and B. subtilis can produce very characteristic aromas in fermented products such as natto and dawadawa (also referred to as daddawa). Moreover, the hydrolytic capabilities of these microorganisms can result in a precursor-rich environment, which is useful for subsequent reactions leading to flavour production. A 1995 patented process demonstrated the ability to produce a fermented flavouring composition with the use of Bacillus spp. Hydrolysed protein obtained after fermentation with Bacillus spp. is mixed with reactive flavour precursors, which are subsequently heated to induce flavour formation and can be dried to a powder format. The product of this patented process imparts a basic meaty flavour, with a reduced yet characteristic dawadawa-like aroma. This paper briefly summarises some of the characteristics and uses of traditional dawadawa and illustrates alternatives described in the patent for the production of a process flavour base. Issues and considerations for the industrialisation of a fermentation process are briefly discussed, as well as some future opportunities for development and exploitation of traditional fermentation technology.