Effect of pre-gelatinization on the qualities of extruded whole Tartary buckwheat noodles

Extrusion processing can improve the quality of gluten-free noodles by promoting starch gelatinization. However, the sequential processing effects of pre-gelatinization followed by extrusion on the cooking quality of whole Tartary buckwheat noodle (WTBN) remain rarely elucidated. This study systematically investigated the effects of superheated steam (SS) and conventional steam treatment on the properties of extruded WTBN. The results showed that the steam processing significantly increased the optimal cooking time of WTBN from 18 min to 21 min at 70°C. Pre-gelatinization of Tartary buckwheat grains enhanced starch thermal stability and gel network strength, which reduced cooking loss by 44.67%- 66.20%, and decreased the breakage rate by 18.75% when cooked at 100 °C, while also improving texture and tensile properties of WTBN. Conventional steam treatment resulted in a denser gel network, which contributed to higher hardness and lower cooking loss. In contrast, SS with its higher heat transfer efficiency exerted a stronger disruptive effect specifically on unstable regions within the starch crystal structure, leading to structural stabilization and enhanced interactions between water and other components. These complementary effects collectively contributed to the quality improvement of extruded WTBN. • Tartary buckwheat grains were pre-gelatinized by steaming and superheated steam • Gluten-free noodles were made with 100% whole buckwheat flour using extrusion • Pre-gelatinization and extrusion contributed to forming the gel network of noodles • Extruded noodles cooking at 70 °C gave a better moisture-distribution and texture