Recently, researchers from Fruit and Vegetable Processing and Nutrition & Health Innovation Team from the Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences (IFST-CAAS) revealed the effects of apple pectin molecular weight on the gelatinization and gelation properties of wheat starch and its underlying mechanisms. The related research results have been published in the internationally renowned journal Food Hydrocolloids (JCR Q1, IF=12.4). Kaiyue Liu, a master's student at IFST, is the first author, with Professors Jinfeng Bi and Jianyong Yi as co-corresponding authors. This work was supported by the National Key Research and Development Program of China (No. 2024YFD2100603).

Wheat starch is an important industrial raw material, but its relatively poor thermal stability, long dissolution time, and high retrogradation tendency limit its broader applications to some extent. Modified starches can better meet the industry's demands through optimized physicochemical properties. Apple pectin, widely used in beverages, jams, gummies, and other industries, is a high-quality water-soluble dietary fiber that can regulate blood sugar and promote gut health. This study explored how the addition of apple pectin regulates the physicochemical properties of wheat starch, clarified the interaction mechanisms between them, and provided new methods for the optimization of the functional properties of wheat starch and its products.

In this study, apple pectin with different molecular weights (3.46-350.25 kDa) was added to wheat starch to analyze its effects and interaction mechanisms on wheat starch gelatinization, rheological, thermal, and gelation properties. The results showed that high-molecular-weight apple pectin could increase the peak viscosity of wheat starch gel by 270%, enhance viscoelasticity by about 213%, reduce transmittance by about 54%, raise the gelatinization temperature to 85.65°C, and significantly improve the orderliness and stability of the starch gel structure. Hydrogen bonding was identified as the main intermolecular interaction between apple pectin and wheat starch. The addition of high-molecular-weight apple pectin significantly increased the number of hydrogen bonds in the starch gel, altered water molecule adsorption capacity, and effectively enhanced thermal stability and rheological properties.

This research provides theoretical and technical support for quality regulation of wheat starch-based products and is of positive significance for enhancing the added value of the wheat and apple industries.

Article link: https://doi.org/10.1016/j.foodhyd.2025.111912

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