LACTIC-ACID FERMENTATION OF CASSAVA DOUGH INTO AGBELIMA

The souring of cassava dough during fermentation into the fermented ca ssava meal, agbelima, was investigated. Four different types of tradit ional inocula were used to ferment the dough and increases in titrable acidity expressed as lactic acid from 0.31-0.38 to 0.78-0.91% (w/w) c onfirmed the fermentation to be a process of acidification. The microf lora of all inocula and fermenting dough contained high counts of lact ic acid bacteria, 10(8)-10(9) cfu/g in all inocula and 10(7)-10(8), 10 (8)-10(9) and 10(9) cfu/g at 0, 24 and 48 h in all fermentations. Lact obacillus plantarum was the dominant species of lactic acid bacteria d uring all types of fermentation accounting for 51% of 171 representati ve isolates taken from various stages of fermentation. Other major lac tic acid bacteria found were Lactobacillus brevis, 16%, Leuconostoc me senteroides, 15% and some cocci including Streptococcus spp. whose num bers decreased with fermentation time. The lactic acid bacteria were r esponsible for the souring of agbelima through the production of lacti c acid. All L. plantarum, L. brevis and L. mesenteroides isolates exam ined demonstrated linamarase as well as other enzymatic activities but did not possess tissue degrading enzymes like cellulase, pectin ester ase and polygalacturonase. The aroma profile of agbelima did not vary with the type, of inoculum used and in all samples the build-up of aro ma compounds were dominated by a nonidentified low molecular weight al cohol, l-propanol, isoamyl alcohol, ethyl acetate, 3-methyl-1-butanol and acetoin. Substantial reductions occurred in the levels of cyanogen ic compounds present in cassava during fermentation into agbelima and detoxification was enhanced by the use of inoculum.