Modification of Tartary buckwheat flour via steam explosion and the quality characteristics of corresponding gluten-free whole-grain cookies

Abstract

Steam explosion (SE, at 0.3–0.7 MPa for 3–7 min) was employed to modify the physicochemical properties of Tartary buckwheat (TB) flour, and the eating quality and starch digestibility of corresponding gluten-free whole-grain TB cookies was assessed. The results illustrated that SE enhanced the water-extractable arabinoxylans content in TB flour by 24%–152%. SE increased the random coil content while decreasing the α-helix content, and starch of SE flours had lower relative crystallinity and degree of short-range order. The water-holding capacity significantly increased with SE at moderate conditions. Additionally, SE flours enhanced the spread ratio of the cookies. Compared to cookies made with native TB flour, the digestibility of starch in cookies made with SE flour was significantly lower, and their resistant starch content was higher. The sensory evaluation attributes of SE cookies were superior to those of native cookie in terms of texture, smell, and form attributes. This study elucidates the action mechanism of SE modification on the properties of TB flours and cookies, offering a reference for the application of SE treatment on whole grain processing.