Physicochemical characteristics and glycemic index of bread made from purple sweet potato flour, starch, fiber from solid waste of starch processing

Abstract

This research was purposed to evaluate the characteristics of physicochemical, and glycemic index of bread made from purple sweet potato (PFSP) flour, starch, and fiber (solid waste of PFSP starch processing). The resulting breads were tested for the physicochemical characteristics and using non factorial completely randomized design as research design with 3 types of ingredient used in bread making as a treatment, namely composite flour from a mixture of PFSP flour, starch and fiber with a ratio 75: 5: 20; 100% PFSP flour, and 100% wheat flour. The results showed that differences in flour had a very significant effect on color, texture profile, ash, protein, fat, and total sugar content of bread. Bread made from composite flour in the form of a mixture of PFSP flour, starch and fiber flour, and also bread made from 100% PFSP flour has higher dietary fiber content than bread made from wheat flour. The daily energy sufficiency of the three types of bread is 10-12%. The glycemic index of bread made from composite flour, PFSP flour, and wheat flour were 41.3, 42.1, and 46.3, respectively, which were classified as low categories. Based on the results, PFSP flour, starch, and fiber flour can be used as wheat flour alternative in making bread.