Effect of microwave treatment on the structural components and in vitro digestibility of wheat flour starch

Title : Effect of microwave treatment on the structural components and in vitro digestibility of wheat flour starch

Abstract:

High consumption of products made with refined wheat flour, such as bread, has been associated with rapid starch digestion and sharp increases in blood glucose. This has driven the search for technological strategies to modulate starch digestibility and improve the nutritional quality of food products. Thus, this study explores the effect of microwave treatment on wheat flour, specifically on the structural properties of its components and the physicochemical and digestibility characteristics of breads. The experiment was designed as follow: Commercial wheat flour was subjected to dry heat microwave treatment (3.2 W/g) using a domestic microwave oven. The treatment time (15, 30, 60, and 120 s) was used as a control variable to evaluate the effect on the structural properties of the flour components (water, protein, starch), based on XRD and FTIR analyses; and on the physicochemical properties, such as color, texture, and in vitro starch digestibility, of the resulting breads. The results show that relatively short treatment times affect most structural properties, with only the relative crystallinity of the starch remaining almost intact. The water structure changed from predominantly low to high-density. The secondary structure of the proteins shifted towards higher α-helix content at the expense of β-sheet content. The short-range order of the starch increased with treatment time. Bread made with the treated flour was softer. Furthermore, the resistant starch content increased by 50%, accompanied by a reduction in rapidly digestible starch. Analysis showed that the water structure in the treated flour played a significant role in modifying the molecular organization of wheat flour, as well as in the digestibility of the starch in the bread. Overall, the results of this study suggest that microwave treatment of wheat flour prior to baking is a viable alternative for producing wheat bread with a reduced glycemic index and improved nutritional properties.

Biography:

Alfonso is a PhD student in Biotechnology at the Universidad Autonoma Metropolitana, Mexico. With expertise in Food Science and Technology, he specializes in the use of colloids and polymers and their applications for protecting bioactive compounds and obtaining functional and nutritional foods. He studies how interactions between structural components affect the physicochemical and digestibility properties of food products. He has made significant contributions to research such as the Microencapsulation of betalains by foam fluidized drying. His research interests include using technologies, colloids, and polymers to structure starch-based foods, aiming to reduce digestibility and thus obtain more nutritious and functional foods.