Evaluation of the effect of fermentation of African oil bean (Pentaclethra macrophylla) using bacillus subtilis as starter and Lactobacillus fermentum as adjunct on the vitamin and mineral contents of the seeds
Nwanagba NL, Ojimelukwe PC, Ezeama CF
Effect of starter culture fermentation and the use of an adjunct starter on the vitamins and mineral composition were investigated. Preliminary experiments were carried out to determine the best conditions (pH, temperature and organoleptic properties) for the use of Lactobacillus fermentum as an adjunct to Bacillus subtilis in fermenting African Oil Bean seeds. African Oil Bean was processed and subjected to different fermentation methods: (a) use of B subtilis as a monoculture (b) use of L. fermentum as monoculture culture (c) use of B. subtilis and L. fermentum as mixed culture (d) traditional/chance fermentation. The fermentation process lasted for a period of 96 h. After drying the 96 h fermented African Oil Bean samples at 50 0C for 3 h, the samples were evaluated for vitamin (B1, B2, B3, C, A and E) and mineral (Ca,P, Fe and Zn) composition. Preliminary experiments showed that L. fermentum can serve as an adjunct culture to B. subtilis at pH of 6.30 and temperature of 36.5 0C after 24 h fermentation of African oil bean with B. subtilis. Fermentation was observed to increase the mineral and vitamin contents of African Oil Bean samples. The calcium content ranged from 212 to 256mg/100g, magnesium content ranged from 176 to 219mg/100g, phosphorus content ranged from 186 to 234mg/100g, Iron content ranged from 9.25 to 10.58 mg while zinc content ranged from 5.33 to 9.60mg/100g for all the samples.