Wheat bread supplemented with potato peelflour: color, molecular organization, texture CONTENIDO and in vitro starch digestibility

In this work the physical characteristics and in vitro digestibility of breads made from blends of wheat flour and potato peel flour(PPF), with weight percentage of PPF of 0, 5, 10, 15 and 20 g/100 g were studied. Thermal gravimetric analysis (TGA) showed that the PPF addition accelerated the weight loss with the temperature. Fourier transform infrared (FTIR) analysis revealed PPF induced changes in the bread molecular organization, with an increase of cluster-like water structures, a decrease of the beta-sheet protein structures and an increase of amorphous starch arrangements. PPF addition also led to bread with decreased relative volume and increased hardness, which was linked to the disruption of the starch and protein structures. In contrast, starch digestibility showed a marked decrease, of the rapidly digestible starch fraction. A multivariate Principal Component Analysis (PCA) showed that thein vitro starch digestibility is linked to the water and starch structures. Overall, the results showed that the addition of up to 10 g of PPF/100 g wheat flour is a viable option for obtaining a bread with decreased starch digestibility and similar overall quality properties of a full wheat bread control