Abstract:
In Ethiopia about 65% of the children are protein malnourished. To decrease the rate of malnutrition, formulation and development of protein rich food from nearby and readily available cereals such as soybean, quality protein maize and peanut are important. This study focused on development and optimization of the blending ratio and baking time for protein-rich snack bars from Peanut, Soybean, and Maize. The experiment was scheduled with two factors: blending ratios (45:35:20, 40:40:20, 35:40:25, 45:40:15, 40:35:25, and 45:30:25 for maize, peanut and soybean respectively) and baking times (30,40, and 50 min). Eighteen combinations of treatments were executed using crossed D optimal in design expert Effect of blending ratio, baking time and their interaction on sensory acceptability (color, flavor, crispiness, graininess, and overall acceptability), anti-nutritional factors (phytic and condensed tannin), and proximate composition (crude protein, crude fat, crude fiber, total ash, total carbohydrate, energy calcium, iron and zinc contents) of protein dense snack bar were studied. The proximate composition of snack bar including 13.67-14.97% crude protein, 25.13-29.85 % crude fat, 0.66-1.56% crude fiber, 2.49-2.96% ash, 44.84-48.85% carbohydrate and 482.4 to 498.3Kcal/100g of energy content showed significant (P<0.05) difference due to blending ratios. The sample with 35%maize, 40%peanut, and 25%soybean were high in protein and fiber. The increase in soybean and peanut leads to the increment in crude protein and crude fiber content of snack bar. The mineral content such as calcium, iron and zinc of protein dense snack bar were also significantly (P<0.05) affected. Calcium and iron content of snack bar were increased due to the increase in maize, and soybean had direct relation with the values of zinc. Sensory acceptability statistics of snack bar presented that increasing the blending ratio of soybean resulted in increased scores of all attributes while an increase in baking times decreased the values significantly (P<0.05). The Tannin and phytic acid contents ranged from 5.67 to 5.90mg/100g and 189.5 to 191.4 mg/100g, respectively. Phytic acid were significantly(P<0.05) different due to both baking time and blending ratio but tannin was significantly(P<0.05) affected by blending ratio only. Among all samples constraint 43.17% maize, 37.03% peanut, and 19.80% soybean, baking time for 35:18sec are recommended to develop protein rich snack bar.