Modeling the effect of thermal combined with high‐pressure treatment on intramuscular lipid oxidation in pork

The kinetics of lipid oxidation in pork during high-pressure combined with thermal (HP-T) treatment were studied within the condition range of 300-600 MPa and 20-60 degrees C. Results showed that the lipid oxidation rate constants (k values) increased with increasing pressure or temperature. Lipid primary oxidation exhibited higher k values than secondary oxidation at each investigated pressure-temperature. At the studied pressure range, the temperature dependence (activation energy) of both primary lipid oxidation and secondary lipid oxidation rate constants decreased with increasing pressure; while the highest sensitivity of lipid oxidation rate constants to pressure (activation volume) was observed at 30 degrees C for primary oxidation, and 40 degrees C for secondary oxidation. Four kinetic models for lipid oxidation basing on Arrhenius and Eyring equation were established successfully. Practical Applications High pressure processing plays a more and more important role in food industry, however, the application of this technology in animal products is limited because of increased lipid oxidation due to high pressure treatment, the reason for which reported by different authors is inconsistent. To better understand the real causes of lipid oxidation induced by high pressure and control it purposefully, the kinetic models for lipid primary and secondary oxidation basing on Arrhenius and Eyring equation were established successfully in this article. In practice, the predetermined combinations of temperature and pressure during HP-T treatment of pork could be evaluated by predicting the effect of these conditions on lipid oxidation using the models established in this study, and thereafter modifying and selecting the optimal treatment conditions. The models should be validated or modified when applied to other types of meat basing on a larger number of experiments.