Effects of orange-fleshed sweet potato (Ipomoea batatas)-Bambara groundnut (Vigna subterranea) composite flour on quality properties of pasta

Abstract

Non-wheat flours are being used to partially replace wheat flour. This is expected to increase the utilization of local raw materials while easing demand for wheat. The goal of the study was to investigate how composite flour derived from orange fleshed sweet potato (Ipomoea batatas (L.) LAM) and Bambara groundnut (Vigna subterranean (L.) Verdc) affects the quality of pasta while also improving its nutritional characteristics. Orange fleshed sweet potatoes (OFSP) were produced at the Agricultural Research Council Roodeplaat Campus in Pretoria, and Bambara groundnuts were sourced from the Thohoyandou area, Vhembe district in South Africa. The OFSP were peeled, sliced, dried for 10 hours at 60℃ using a hot air oven drier and ground into flour. Bambara groundnut flour was made by soaking the seeds in water for 24 hours, dehulling them, drying them in an oven dryer for 24 hours at 60℃, and they were then ground into flour. The pasta was produced from a mixture of semolina, OFSP and Bambara groundnut flours in the ratios 90:5:5; 70:15:15 and 50:25:25. The functional and physicochemical properties of the pasta, as well as its cooking and sensory qualities were investigated. The samples were analyzed in triplicate using a randomized complete block design. The data was subjected to ANOVA and the Duncan multiple range test was used to differentiate significant means. Pasta produced from composite flour significantly affected the proximate composition and cooking quality compared to 100% wheat pasta. Good nutritional quality pasta was obtained from the blend of 50:25:25 semolina, OFSP and Bambara groundnut flour which exhibited a high value of protein (9.73%), ash (4.38%) and fibre (2.27%), vitamin A (1.95mg/100g) and vitamin C (8.93mg/100g) content. The pasta enhanced with composite flour of 70:15:15 semolina, OFSP and Bambara groundnut was mostly preferred during consumer acceptability testing compared to the pasta produced from 90:5:5 semolina, OFSP and Bambara groundnut flour; 50:25:25 semolina, OFSP and Bambara groundnut flour and 100% wheat.