Effect of psyllium and cellulose fiber addition on the structure and the starch digestibility of bread and crackers

Abstract

The purpose of this study was to determine the effect of psyllium and cellulose fiber additions on starch digestion behavior, as well as the structural and textural characteristics of bread and cracker samples. Fiber-added samples were created by replacing 10% of the wheat flour in the recipes with fibers. Fibers reduced the porosity of the bread samples, increased their hardness and chewiness, and decreased the hardness of the crackers. Due to its high water-holding capacity, psyllium fiber interfered more than cellulose fiber with the formation of a gluten network and dough structure. At this concentration, psyllium fiber was effective at slowing the digestion of bread and crackers, whereas cellulose fiber had no effect. Psyllium fiber inhibited starch digestion by acting as a physical barrier and limiting enzyme mobility. Due to the structural differences between bread and crackers, they digested differently. The findings indicated that variations in the development of food structures caused by processing methods and the solubility of the fibers used could have a differential effect on starch digestion. Across the board, food processing methods, ingredients, and textural characteristics can all have an effect on starch digestion. • Psyllium was more detrimental to gluten network and dough structure than cellulose • Psyllium fiber reduced starch digestion whereas cellulose fiber did not • Psyllium fiber functioned as a physical barrier and thickening agent to restrict mobility of enzymes • Processing methods and solubility of fibers affect structure development and texture • Processing method, fiber type and final food texture could alter starch digestion