The Effect Of Gas Pressure On The Dry Consumption And Tissue Structure Of Pork During Freezing Affect The Study

With the increasing improvement of people's living standard,food freezing and refrigeration technology is also constantly improving,and many new technologies are emerging and penetrating into practice.This Paper mainly analyzes the influence of pressure change on pork quality(dry consumption and tissue structure)during the freezing process.Atmospheric pressure 105 Pa 1.01;Pressurized 151000 Pa)conditions of frozen pork,and by using CFD software,the simulation method in this Paper,the analysis of the influence of pressure on frozen pork quality mainly includes: infrared spectroscopy testing pH value and electrolyte microscopy analysis under different pressure through different angles such as freeze on consumption of pork dry water ice crystals juice loss,the influence of such quality results show that pressure changes the frozen environment pressure,increasing the pork and the heat transfer coefficient of air Chambers,reduced the pork and the mass transfer coefficient of air Chambers,which affects the thermal mass transfer and organization structure of frozen pork The pressure freezing reduces the pork dry consumption and improves the pork quality.Firstly,a variable pressure freezing test bench was set up,which mainly designed and modified the tightness of the pressurized freezing device;analyzed the temperature of the experimental center in three operating conditions;and established a physical model and a mathematical model of the pork freezing process under normal pressure.,And simplified assumptions were made,which were simulated and solved by CFD software.The temperature field was basically consistent with the experiment,and an error analysis was performed.Then two experiments were performed on pork that had been frozen under three different working conditions(decompression,atmospheric pressure,and pressure),which contained five indicators(measurement of dry consumption,microscopy,infrared spectroscopy,pH,and electrolyte)Analysis to analyze the impact of different pressures on the tissue structure and quality of pork,including the following:Testing the pork freeze-dry consumption under different pressure(decompression,normal pressure,and pressurization)conditions,the results show that pressurization helps reduce porkfreeze-dry consumption;Under different pressure(decompression,normal pressure,and pressurization)conditions,the micro structure of frozen pork was observed through a microscope.As the pressure increased,the ice crystals formed by frozen pork tissue were more uniformly distributed and the texture was clearer;Using Infrared spectroscopy was used to analyze the quality of pork freeze under different pressures(decompression,normal pressure,pressurization).It was found that variable pressure freeze will affect the level of spectral reflectance,and the peak position change will be less affected;decompression freeze Between 3000~2600cm-1 and 1600~900cm-1,the relative pressure and freezing fluctuations are more chaotic;The pH value of pork was measured under different pressures(decompression,normal pressure,pressurization),and it was found that the pH value of frozen pork under reduced pressure was higher than that of pressurized freezing;The conductivity of pork was measured under different pressures(decompression,normal pressure,pressurization),and it was found that the conductivity of pork after being frozen under pressure was higher than that of the normal temperature unfrozen control group.The conductivity of unfrozen pork at normal pressure of 101000 Pa is about 1198 ppm,and the conductivity of frozen at 151000 Pa under pressure is about 1768 ppm.