Multiple starter cultures fermentation of salted soybean-daddawa- a West African condiment

Abstract

Study had suggested that multiple starter cultures fermentation of soybean-daddawa holds great promise for its industrialization but there is no report on effect of salt (NaCl) inclusion on the optimized process. The present work investigated the influence of NaCl inclusion on multiple starter cultures fermentation of soybean-daddawa. Salted (1%) and salt-free seeds of soybean were fermented into soybean-daddawa using multiple culture systems of Bacillus subtilis LB3, Staphylococcus xylosus SAU3 and Leuconostoc mesenteroides ssp cremoris LAB5. The different fermentation sets were assessed for protease and α-amylase enzyme activities (U/ml), Free Amino Acids (FAA) and Total Soluble Sugars (TSS) (mg/g), pH and Titratable acidity (TTA) (mg/g lactic acid). Sensory evaluation of the products was also carried out. In fermenting salted seeds, protease and α-amylase enzyme activities increased from 396 – 997, and 81- 209 respectively while the corresponding values for the salt-free samples were 414 – 914, 76 –184. FAA contents of fermented salted and salt-free seeds were 30.3 - 36.7 and 30.6 – 38.1 respectively and the values for TSS were 88.8 – 95.3, 85.6 – 106 respectively. At the end of 65 h fermentation, no significant difference (p > 0.05) existed in the pH of all the fermented soybean-daddawa. Sample obtained using mixed culture of Staphylococcus xylosus SAU3 and Leuconostoc mesenteroides ssp cremoris LAB5 resulted in the highest TTA value of 4.3 mg/g lactic acid in the fermented salted seeds.. All the fermented seeds were organoleptically acceptable to the soybean-daddawa consumers but the panellist demonstrated highest preference for salted soybean-daddawa fermented with the ‘cocktail’ culture of Bacillus subtilis LB3, Staphylococcus xylosus SAU3 and Leuconostoc mesenteroides ssp cremoris LAB5. Results of the present study suggest that inclusion of NaCl (1%) has the capability of consolidating on the potentials of multiple starter culture fermentation of soybean-daddawa. This holds a great promise for subsequent industrialization of soybean-daddawa production.