Quality Evaluation of Maize Akamu as Affected by Dehulling, Partial Germination and Oil Seed Supplementation

Abstract

Akamu, a starchy cereal-based lactic acid fermented gruel consumed in West Africa was prepared using different processing methods: use of dehulled (D) maize grains, use of partially germinated (PG) maize grains (36-48h) and blends: PG and soybean (S) (90:10), D and S (90:10) and D and Melon (M) seed (90:10). Soaking, wet-milling, wet-sieving, sedimentation (24h), decanting, dewatering were involved and the traditional maize akamu served as the control. The seven different samples were subjected to physicochemical microbiological and sensory evaluations. Crude protein (4.70-10.33%), crude fat (4.12-14.30%), total ash (0.26-0.88 %%), crude fibre (1.51-2.77%) contents were higher in oil seed treated akamu and the carbohydrate contents (<74.41%) were the lowest. The akamu made of dehulled(D) maize had poorer proximate composition. Dominant elements in all the akamu were Phosphorous and Potassium and surprisingly, Zinc (1.98mg/100g), Iron (7.33 mg/g) and potassium (106.83 mg/g) in the akamu made with dehulled maize and calcium higher in the control (14.21mg/100g) and partially germinated (14.71mg/100g) akamu. Low water activity in the dried akamu ensured satisfactory low bacterial and fungal counts (<103cfu/g). The control (U) and D akamu possessed better functional and sensory properties; water absorption capacity, swelling power and pH of the different akamu varied significantly: 7.40—8.10 ml/g, 2.74-5.73 g/g, and 5.41-7.42 g/g respectively. Short period of  germination (<48 h) did not affect negatively the proximate composition, sensory, water absorption capacity and swelling power of the PG, PG+U, PG+S akamu(s). The control (U) and D akamu were adjudged to possess better sensory properties especially U akamu with scores slightly greater than 8 on a 9-point hedonic scale, but the superior nutritive value of oil seed treated akamu(s) were masked by poorer sensory attributes. It is concluded that akamu made from PG maize or its blends with undehulled maize or soybean were better alternatives to traditional akamu which is nutritionally inferior although it possessed excellent sensory and functional properties.