Microbiological, Physicochemical and Enzymatic Changes in Fermented African Locust Bean (<i>Parkia biglobosa</i>) Seeds Using <i>Bacillus subtilis</i> and Additives

Abstract

Traditional fermentation of dried seeds ofParkia biglobosais used to produce a local product called ‘iru’. It is a condiment consumed mostly in Western Nigeria. In this study, the effect ofBacillussubtilisBC4333starter cultures and different additives, such as local softening agents called ‘kuuru’,Hibiscus sabdariffaseed cotyledon and ash from cashew (Anacardium occidentals) plants as on the microbiological, physicochemical, and enzymatic properties of fermentedParkia biglobosaseeds were investigated. The dried seeds ofParkia biglobosawere processed by boiling the cotyledons withHibiscus sabdariffa,‘kuuru’ andAnacardium occidentals(cashew plant) ash using natural fermentation andBacillus subtilisstrainBC4333as a starter culture. The fermentations were carried out at 35°C for 36 hrs. Commercially fermented Parkiabiglobosaseed (called ‘iru-pete’) was used as control. All the samples were analyzed for microbial, physico-chemical and enzymatic properties using standard biochemical techniques. ‘Iru’ produced using ‘kuuru’ (IFK) had the highest microbial count of 7.88 log CFU/g, while the microbial count of íru’ produced with ash (IFA) and íru’ produced with dried seeds ofHibscus sabdariffa(IFH) were 7.69 log CFU/g and 7.75 log CFU/g respectively. The pH of the fermented products ranged between 7.06 and 7.91, while the unfermented sample (UFS) had pH 6.68. The unfermented sample had the highest total titratable acidity (TTA) of 2.6×10-2N while the ‘iru’ samples produced using ‘kuuru’(IFK) had the least TTA of 1.0×10-2N. Fermentation significantly increased the moisture content of the products. Starter culture fermented ‘iru’ (F14) had the highest protease, amylase and phytase activity of 232.3UPR, 0.41UAM and 71.85UPH respectively. Findings from this study suggest that ‘iru’ produced by addition ofBacillus subtilisstrain BC4333 had the best desirable biochemical qualities when compared to the other test additives and thus recommened for commercial scale.

Comparative Effects of Fermented and Unfermented Parkia biglobosa Bean Seeds in Diabetic Induced Experimental Rats

“…The method of Omodara and Aderibigbe [15] was modified to prepare the dried African locust bean seeds. After being manually cleaned of dirt, the dried seeds were cooked under pressure for four hours.…”