Functionalities of Octenyl Succinic Anhydride Wheat Starch and Its Effect on the Quality of Model Dough and Noodles

Chemically modified starch is a widely used food additive for tailoring the quality of wheat flour products. However, the effects of octenyl succinic anhydride (OSA)-modified wheat starch with varying degrees of substitution on the quality of dough and noodles remain unclear. In this study, we prepared two types of OSA-modified wheat starch with different degrees of substitution and incorporated them as additives into a wheat starch-gluten protein model flour system to evaluate their impact on dough processing characteristics. Fourier transform infrared (FTIR) spectroscopy results revealed the introduction of ester carbonyl (C=O) and carboxylate (RCOO-) functional groups into the starch structure. X-ray diffraction (XRD) analysis demonstrated that OSA modification reduced the relative crystallinity of starch and disrupted the long-range structural order of the native starch. Scanning electron microscopy (SEM) observations indicated that the surface of OSA-modified wheat starch granules became rougher. OSA modification enhanced the solubility, water absorption capacity, and apparent viscosity but lowered the gelatinization temperature of starch, making starch more prone to gelatinization. Furthermore, the incorporation of OSA-modified wheat starch significantly altered the gelatinization behavior and dynamic rheological properties of wheat dough, whilst the noodle with the addition of OSA-modified starch (DS = 0.019) reduced the cooking time by 29.0% compared to the control group noodle and improved its water absorption rate. This study provides a theoretical foundation for the application of OSA-modified wheat starch as a food additive in wheat-based foods.