Evaluating the nutritional and sensory quality of bread, cookies and noodles made from wheat supplemented with root tuber flour

Abstract

PurposeDue to the rise in urbanization, demand for easily prepared foods such as pastries and noodles has risen. But the high price of wheat in the global market puts financial stress on low-income people, especially on those living in tropical regions, where wheat does not thrive well. They depend solely on imported wheat, which is expensive due to importation cost, or seek other relatively less-nutritious cereals. Therefore the purpose of this paper is to investigate the possibility of supplementing wheat flour with flour from relatively cheap and easy-to-produce root tuber, such as cassava, potato and sweet potato.Design/methodology/approachStrong-, medium- and weak-gluten wheat flours were supplemented with flour from cassava, potato and sweet potato at 10, 20 and 30 percent. Strong gluten composites were used to make bread, whereas medium and weak gluten composites were used for cookie and noodle production, respectively. Protein, ash, fat, crude fiber, moisture, carbohydrate, gluten, zeleny and energy contents of each composite were tested.FindingsThe nutritional and sensory quality of bread, cookies and noodles made from wheat flour supplemented with root tuber flour at 10, 20 and 30 percent was assessed. Results revealed that mixing wheat flour and root tuber flour has important effects on the moisture, protein, carbohydrate, fat, ash, gluten, zeleny sedimentation value and crude fiber content of the resulting mixture. Moisture and carbohydrate increased while protein and fat significantly (p<0.05) decreased with increasing root tuber flour levels in formulations. Gluten content also decreased significantly with rising root tuber flour concentrations. There was a mild reduction in bread’s general acceptability at 10 and 20 percent in potato composites; thus potato flour was still acceptable at 20 percent. Cassava flour composite also topped with a general acceptability score of 69.26 at 20 percent in cookies, whereas sweet potato composite achieved a score of 84.81 in noodles.Originality/valueThis work has successfully confirmed that wheat flour could be supplemented up to 20 percent with root tuber flour without compromising the nutritional and sensory quality of products. It has also demonstrated that different products require different root tuber flour substitution for optimum results. Potato at 10 percent substitution was found to be best for bread production. Cassava and sweet potato at 10 percent substitution were also best for cookies and noodles, respectively. With respect to protein content only, sweet potato substitution is better than cassava and potato.