This study aimed to create a visualization method to control the heat uniformity of pork slices during stir-frying, and to investigate the response of physicochemical properties, edible quality and advanced glycation end-products (AGEs) of stir-fried pork to “Huohou” (low-level fire and high-level fire), which could provide the theoretical support for standardizing the quality of stir-fried meat dishes and promoting the industrialized processing of traditional dishes.

The heat uniformity of the meat slices in the stir-frying process was controlled based on the infrared thermal imaging system, and the changing rules of water and oil content, lipid oxidation and Maillard reaction of meat slices in stir-frying process were investigated under different “Huohou”. The edible quality of the sample was assessed by determining the color and shear force. Subsequently, the reasons for the evolution of pork tenderness were analyzed by measuring T₂ relaxation time and protein secondary structure. Finally, correlation analyses were performed to reveal the correlations of lipid oxidization and the Maillard reaction with AGEs.

At the same stir-frying time, the water content and tenderness of the low-level fire group were significantly higher than those of the high-level fire group, and the oil content was significantly lower than that of the high-level fire group. During the stir-frying process, the thiobarbituric acid reactive substances (TBARS) and absorbance value at 420 nm (A₄₂₀) of the meat slices from the high-level fire group were higher than those from the low-level fire group, indicating that increasing “Huohou” accelerated the lipid oxidation and the Maillard reaction. After stir-frying for 4 min, the decrease in T₂₁ relaxation time of meat slices from the high-level fire group was 1.39 times that from the low-level fire group, which indicated that muscle contraction was intensified, and the myofibrillar distance was further reduced with the increase of “Huohou”. Compared with the low-level fire group, the high-level fire group had more ordered β-sheets transformed into random coils, suggesting that the degree of protein denaturation in the meat slices from the high-level fire group was higher than that of the low-level fire group. Meanwhile, the meat slices from high-level fire group experienced more severe contraction and protein denaturation, resulting in lower tenderness than those from low-level fire group. Combined with the results of the center temperature of the meat slices, high-level fire stir-frying took less time for samples heated to the same center temperature. High-level fire-treated meat slices experienced shorter periods of oxidation and thermal denaturation, making it easier to obtain safer and chewing-friendly meat products compared with low-level fire-treated meat slices. In addition, correlation analysis showed that lipid oxidation contributed more to the generation of AGEs than the Maillard reaction.

The application of infrared thermal imaging system solves the problem of limited research related to the stir-frying process caused by different degrees of doneness in the same pot. “Huohou” could be used to achieve control of the product's edible quality by regulating the water-oil migration, lipid oxidation, Maillard reaction, and protein structure of the meat slices in both time and temperature dimensions.