Starch coating with carbon dots: A promising coating to enhance the freeze-thaw stability of meatballs.

In this study, composite coatings were developed by incorporating carbon dots (CDs) to cross-linked starch (S). The effects of CDs on the coating structure and the quality of meatballs during freeze-thaw cycles were investigated. The results showed that after five freeze-thaw cycles, the sample containing 0.3 mg/mL CDs (S + 0.3CDs) exhibited significant structural and functional improvements compared to the S group. The short-range order of starch, represented by the R1047/1022, decreased to 1.15, accompanied by a 3.14 % reduction in crystallinity and a 30.52 % decrease in syneresis rate. These modifications contributed to enhanced meatball quality: The freeze-thaw loss, cooking loss, thiobarbituric acid reactive substances, and total bacterial count decreased by 4.24 %, 22.34 %, 29.68 %, and 19.25 %, respectively. Additionally, the S + 0.3CDs coating delayed lipid oxidation and microbial proliferation during storage. This study demonstrates that the addition of CDs optimally improves the freeze-thaw stability of the coating and the preservation effect of meatballs, providing a promising strategy for the development of high-performance coatings for frozen foods.