Effect of fermentation periods on the nutrient quality and sensory acceptability of Africa Yam Beans (<i>Sphenostylis sternocarpa</i>) porridge

Abstract

This study evaluated the effect of fermentation periods (24, 48 and 72 h) on the nutrient quality and sensory acceptability of African yam bean (AYB) porridge. The result shows significant (p<0.05) effect on the nutrient composition and sensory scores of AYB porridge due to fermentation periods. The unfermented (control) AYB porridge had higher values of fat (7.78%), fibre (4.31%) and ash (2.94%) than the 24 h, 48 h, and 72 h fermented porridge. The reverse was the case as 24 h, 48 h and 72 h fermented porridge had higher values of protein (27.87%, 28.90%, 30.80%) than the unfermented porridge (26.35%). The range of the mineral values for Ca (22.74 - 28.06 mg/100g), Mg(10.88 - 26.13 mg/100g), K (115.25 - 140.86 mg/100g) and anti-nutrients for phytate (0.02 – 0.15 mg/100g), oxalate (0.25 – 4.82 mg/100g), tannin (0.93 – 8.46 mg/100g) showed a decreasing trend from unfermented porridge > 24h > 48 > 72 h fermented porridge, respectively. Fermented porridge especially at 24 h, and at 48 h had better sensory acceptability scores than the unfermented and 72 h porridge. The total microbial population in the fermented liquor indicates that Total Viable and Lactobacillus counts increased with increasing fermentation period, that is, from 24 to 72 h, while total Fungal count decreased from 24 to 72 h fermentation period. This study shows that fermentation periods have significant effect in increasing the nutrient quality of AYB porridge for improved human nutrition and in amelioration of hidden hunger.

Keywords: African yam bean porridge, Fermentation periods, Nutrient quality, Sensory acceptability, improved nutrition