*3.1.2 Soumbala*

*New Advances on Fermentation Processes*

the locust bean seeds for 12–24 h, followed by manual de-hulling to remove the seed coat. The de-hulled cotyledons are collected and washed thoroughly and then boiled again for 1 h. The cotyledons are placed in jute bags or wrapped with banana leaves and allowed to ferment for 2–4 days at ambient temperature. During fermentation, the pH increases from near neutral to 8.1 or higher due to the breakdown of protein to amino acids and ammonia. As with other traditional processes, inoculation is usually fortuitous from production environment and equipment used or (rarely by back slopping). Microorganisms that drive the process are predominantly species of *Bacillus* [14, 40]. Other associated organisms include *Staphylococcus* [41], but the roles of these minor populations are contentious. At the end the product is

sticky, with pungent odor and covered with mucilaginous grayish layer.

*Dawadawa* is the most scientifically studied traditional seasoning in West Africa. Several studies designed to improve the traditional process of have been published [41, 42]. **Figure 3** shows a modified procedure for *dawadawa* production [43]. Although, many African alkaline seasoning agents are still produced by the old-aged traditional cottage and kitchen processes, the preparation of some condiments like *dawadawa* has achieved pilot commercial status and is now considerably carried out on large scale by

**22**

**Figure 3.**

*Flow chart for the modern production of dawadawa. Source: [15, 31, 38].*

*Soumbala* is a traditional condiment popular in Burkina Faso and other countries in West and Central Africa. It is also known by different names by different local communities [45]. Similar to *dawadawa*, it is prepared by solid state alkaline fermentation of African locust beans. It contributes significantly to protein nutrition of the consumers. The traditional process for preparing *soumbala* is uncontrolled and similar to *dawadawa* with minor variations based on ethnic preferences. The principal microorganisms involved in the fermentation of *soumbala* are *Bacillus* spp. [34]. The ability of *Bacillus* species involved in *soumbala* fermentation to inhibit undesirable bacteria including *Bacillus cereus* and *E. coli* has been reported [46–48].
