NOVEL FOOD PRODUCT FROM BLENDS OF OFSP, MAIZE AND EDIBLE AGRO WASTE (OKARA): IMPLICATION FROM WASTE TO WEALTH

Abstract

Okara is a huge (35%) by-product generated from soymilk processing. It contains about 24% protein (dry weight) among other nutrients. The huge quantities of okara produced annually pose a significant disposal problem in Nigeria due to increase in soymilk production. Hence the aim of this study is to research into its food use. Composite blend made up of okara, residue from Orange-Fleshed Sweetpotato (OFSP) beverage processing and maize flours were evaluated for suitability in snack preparation. Simplex Centroid Design (SCD) - experimental software package was used to formulate blends of fourteen (14) runs, each was mixed to obtain dough of 45.88g/100g moisture content and then extruded using a single screw extruder. Proximate compositions of the flour were analyzed. The white maize flour had moisture content 9.47, crude protein 1.17, fat 0.00, ash 2.22, and carbohydrate 81.14%; OFSP flour had moisture content 11.55, crude protein 5.14, fat 8.35, ash 2.55,and carbohydrate 72.42%, okara had moisture content 8.85, crude protein 23.58, fat 20.00, ash 2.21,and carbohydrate 45.36% while the extruded snacks had moisture content 12.15, crude protein 20.83, fat 15.43, ash 2.51,and carbohydrate 49.05%. The extrudates (Nobel snacks) were subjected to sensory evaluation. Blend ratio of 80:10:10 and 67:17:17 (OFSP: okara: white maize) were mostly acceptable and were not significantly different (p>0.05) from each other in term of colour and aroma. However snack from 67:17:17(OFSP: okara: white maize) was mostly acceptable and significantly different (p<0.05) from all other extrudates in terms of texture, taste, mouth feel and general acceptability. Four of the extrudates (E181, E055, E161, and E066) were not generally acceptable. The uunder mentioned were the pasting properties of the flour used for the blend formulation: peak viscosity was 422.00, 229.0 and -29.00 RVU; trough 353.67, 130 and -31.0 RVU; break down 100, 68.33 and 2.0 RVU; final viscosity 1091.7, 227 and -26.0 RVU; set back 738, 97 and 5 RVU; peak time 7,6.33 and 4 RVU; pasting temperature 87.3, 85.1 and 81.500C for maize flour, OFSP flour and Okara in all cases. It can be concluded that Snack processing using OFSP: Okara : Maize in ratio 67:17:17 is feasible.