Mechanism of the synergistic enhancement of digestive resistance in steamed cold noodles by V-type starch-tea polyphenols interactions

In this study, V-type wheat starch-tea polyphenols complexes (VS-TP) were used to improve the digestive properties and quality characteristics of steamed cold noodles. With TP content increasing from 2.5 % to 10.0 %, the storage modulus of VS-TP complexes decreased from 580.59 to 1341.85 Pa to 379.90–859.61 Pa, likely due to TP disrupting starch chain entanglement via noncovalent interaction (hydrogen bonds and CH–π bonds). TP also enhanced both short-range and long-range ordered structures of V-type starch, and the complexation index rose from 23.76 % to 84.61 % as TP content increased. Notably, the VS-10 %TP group showed a 47.28 % higher resistant starch content than the control group, which may be attributed to TP-V-type starch interactions and TP's amylase inhibition. However, the lightness, hardness, and gumminess of the steamed cold noodles decreased by 7.84 %, 51.46 %, and 49.84 % when adding 10 %TP. Balancing functionality and quality, 5 %TP was optimal for preparing low-digestibility steamed cold noodles with excellent textures.