Effects of Taro Varieties and Blending Ratios on Proximate Compositions and Anti-Nutritional Factors of Taro (Colocasia esculenta) –Wheat (Aestium triticium) Composite Bread

Abstract

Although taro is widely grown in Ethiopia, it is one of the underutilized crops which is a good source of carbohydrate and minerals. This experiment was conducted to explore the effects of taro varieties and blending ratios on proximate compositions, anti-nutritional factors and sensory qualities of taro-wheat composite bread. Three levels of taro verities (Danu No34, Kiak No33 and local), three levels of blending ratios (10g, 20g and 30g of taro in 100 g of control wheat flour were used and the treatments were factorial arranged in complete randomized design with three replications. Blending with Danu No34, Kiak No33 and local varieties had reduced moisture content to 4.42%, 3.85% and 3.78% respectively as compared to the moisture content (5.2%) in the control (100% wheat bread). Similarly, protein content dropped to 31.1%, 27.87%, 30.28% from 36.79%,crude fat content, 5.05%, 5.31% and 4.34% from 5.4% and energy 407.54 kcal/100g, 410.07 kcal/100g, and 405.73 kcal/100g, from 421.63 kcal/100g, increased iron content 69.01mg/kg/, 87, 98mg/kg and 97.92mg/kg from 52.40mg/kg, crude fiber content increased to 3.48%, 2.32% and 3.31% from 2.67% and utilizable carbohydrate content increased to 62.59%, 63.74% and 62.73% from 52.30%. There was a significant difference in oxalate content due to blending ratios and as the blending ratio increases the oxalate content also increased. The Phytet content in this study was higher than the values of taro (85.47 mg/100 g) reported by Alcantara et al. [1], the values of raw Anchote (20.65 mg/100 g) reported by Habtamu [2], the values of taro ((115.43mg/100g) reported by Adane et al. [3], far below FAO. It could be concluded that the substitution of taro flour with wheat flour in bread making with substitution level up to 20g did not adversely affect the quality properties of the bread and produce bread comparable to that produced from wheat flour. Further studies are required to investigate the impacts on taro flour storage period.