Volatile compounds of Soumbala, a fermented African locust bean (Parkia biglobosa) food condiment

Abstract

Aims: To determine the profile of volatile compounds responsible for the aroma of Soumbala produced spontaneously and with pure and mixed cultures of Bacillus subtilis and Bacillus pumilus. Methods and Results: Traditional and controlled fermentation trials of African locust bean with pure and mixed starter cultures of B. subtilis (B7, B9 and B15) and B. pumilus (B10) were performed. Aroma volatiles were analysed using Likens-Nikerson method coupled with gas chromatography and mass spectrophotometry. Sensory analysis of Soumbala as well as rice dishes prepared with each type of Soumbala were carried out by 10 panellists. In total 116 compounds were identified. They included pyrazines, aldehydes, ketones, esters, alcohols, acids, alkanes, alkenes, amines, pyridines, benzenes, phenols, sulphurs, furans and other compounds. Using principal component analysis for comparison, the aroma profiles of the Soumbala samples could be separated into three groups. The sensory evaluation showed variable acceptability. However, it was noticed that Soumbala samples produced with starter cultures were scored higher than traditionally prepared Soumbala. Conclusions: Aroma volatiles and organoleptic properties of Soumbala vary according to the Bacillus isolates involved in the fermentation. Significance and Impact of the Study: This study contributes to the selection of Bacillus starter cultures for controlled production of Soumbala.

Volatile compounds produced by Bacillus species alkaline fermentation of bambara groundnut (Vigna subterranean (L.) Verdc) into a dawadawa-type African food condiment using headspace solid-phase microextraction and GC × GC–TOFMS

“…[11] Pyrazines, aldehydes, ketones, esters, alcohols, acids, alkanes, alkenes, benzenes, phenols, sulphurs, and furans groups were identified in dawadawa produced from African locust bean and soybeans. [8,12] However, volatile compounds that characterize dawadawa-type African food condiment produced from the controlled alkaline fermentation of bambara groundnuts have not been reported previously.…”

“…The methods that have been employed to isolate volatile compounds from fermented African locust bean (dawadawa) were microscale steam distillation low-density solvent extraction, mainly the Likens-Nikerson method [8,11,12] and purge-and-trap onto Tenax [10] extraction for fermented soybean (soy-dawadawa), followed by gas chromatography-mass spectrometry (GC-MS) analysis. The distillation method is employed for volatile compounds extraction, especially when heat-labile compounds need to be extracted.…”

Aroma profile of gowe, a traditional malted fermented sorghum beverage from Benin

“…This may have been due to the accelerated saccharification process where the product was kept at 40°C for 2 h. Most of the volatile compounds increased with the fermentation time when the yeasts were used in single or in association with the LAB. The ability of selected microorganisms to modify taste, flavors and other characteristics of fermented products has been studied by several authors (Annan et al, 2003b, c;Mugula et al, 2003;Zorba et al, 2003;Gran et al, 2003;Ouoba et al, 2005;Azokpota, 2005). Fermentation of maize dough involving yeasts induced higher concentrations of compounds related to yeasts fermentation products such as alcohols and esters (Annan et al, 2003c).…”

Microbiota of Tayohounta, a fermented baobab flavour food of Benin

“…Volatile compounds resulting from the metabolic activities of Bacillus spp. contribute significantly to flavour during the fermentation of African locust beans to produce soumbala (Ouoba et al, 2005) or soya beans to produce natto or thai thua-nao (Leejeerajumnean et al, 2001). As such, many volatile compounds were found in Beninese afitin, iru and sonru (Azokpota et al, 2008).…”