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

Abstract

The reports on the volatile compounds of a dawadawa-type African food condiment produced from the alkaline fermentation of bambara groundnut (Vigna subterranea (L.) Verdc.) using Bacillus starter cultures are limited. Volatile compounds were isolated from dawadawa-type condiments using headspace solid phase microextraction and analysed by comprehensive gas chromatography coupled to time of flight mass spectrometry. Acids, aldehydes and alcohols accounted for over 70% of the volatile compounds produced in the Bacillus fermented samples. B. subtilis subsp. subtilis SFBA3 produced the highest content of acids (4969.60 µg kg−1), while the highest content of aldehydes (2811.90 µg kg−1) and alcohols (1247.60 µg kg−1) was detected with Bacillus cereus PALB7 and Bacillus licheniformis OALB2, respectively. Sulphur-containing compounds concentration (85.80 µg kg−1) was highest for Bacillus amyloliquefaciens SFBA2. Maximum 2-methyl butanoic acid and 3-methyl butanoic acid concentrations, indicative of typical dawadawa aroma, were produced by B. subtilis subsp. subtilis SFBA3.

Keywords

• Alkaline fermentation
• Bacillus species
• Dawadawa
• Bambara groundnut
• Volatile compounds
• Headspace solid phase microextraction (SPME)
• Gas chromatography–time of flight mass spectrometry (GC × GC–TOFMS).