Effect of Pregelatinized Rice Starch on the Quality and Freeze–Thaw Stability of Glutinous Rice Dumplings

The rapid expansion of the frozen glutinous rice dumpling (GRD) industry faces the challenge of quality deterioration caused by freeze–thaw cycles during product distribution. Pregelatinized starch has been reported to improve the freeze–thaw stability of starchy foods, but its effect on GRDs remains unclear. In this study, rice starch, which is widely available and low in cost, was used to prepare pregelatinized rice starch (PGRS) to enhance the quality and freeze–thaw stability of GRDs. The effect of adding 2–8% PGRS on GRD quality over 1, 3, and 5 freeze–thaw cycles was investigated using texture analysis, ultraviolet spectrophotometry, differential scanning calorimetry, rheometry, Fourier transform infrared spectroscopy, low-field nuclear magnetic resonance, and scanning electron microscopy. Results showed that appropriate PGRS addition weakened an ordered gel structure, increased bound water content, improved microstructural stability, and reduced gelatinization enthalpy. Throughout testing, PGRS reduced cracking and water loss, enhanced textural properties, and increased soup transparency. This confirms that PGRS can serve as a functional ingredient for improving GRD quality and freeze–thaw stability, offering valuable insights for industrial production.