Establishment and experimental verification of temperature prediction model for quick‐frozen strawberry jetted with dry ice

Abstract In this study, the quick‐freezing model and heat transfer model of quick‐freezing of strawberries with dry ice at different flow speeds were proposed to ensure the quality of quick‐frozen strawberries and control the jetting amount of dry ice. The aim of this study was to investigate the changes of internal and external temperature in the process of quick‐freezing strawberries by jetting dry ice. The quick‐freezing experiment platform of strawberries based on dry ice jetting was built for a quick‐freezing experiment of strawberries at a dry ice jetting flow speed of 0.30 m/s. As indicated by the results, the temperature of strawberries was more uniform under the dry ice jetting speed of 0.30 m/s. The highest and lowest temperature differences between the surface and center of strawberries (the simulated) were 15.7 and 39.7°C, respectively, and the quick‐freezing time of strawberries was 345 s. Compared with the experimental result, the error of quick‐freezing completion time was 5.79%. The differences measured in the experiment were 15.1 and 37.7°C, and the error accounted for 4.73% and 7.89%, respectively. The accuracy of the model was measured, mean relative error = 6.31% and root mean square error = 10.78%. As revealed by the results, the model had high universality and precision and could be used to analyze the temperature change during dry ice jetting‐based quick‐freezing of strawberries. The quality indexes of quick‐frozen strawberries before and after dry ice jetting were found to be better than the standard of quick‐frozen strawberries. Thus, the research results can provide a reference for a further development of energy‐saving and environmental dry ice jetting‐based quick‐freezing equipment.