高压结合热处理条件下猪肉磷脂脂解动力学研究

Phospholipid Degradation Kinetics of Pork during Combined High-Pressure and Thermal Treatments

为探究高压结合热处理对猪肉中磷脂脂解的影响规律,促进高压技术在肉制品工业中的应用,在300~700 MPa和20~60℃压力-温度区域内,研究猪肉中磷脂的脂解动力学。结果表明:磷脂脂解遵循一级动力学,多不饱和脂肪酸(polyunsaturated fatty acids,PUFA)脂解速率常数(k)最高,其次是总磷脂(total phospholipids,PL),单不饱和脂肪酸(monounsaturated fatty acids,MUFA)和饱和脂肪酸(saturated fatty acid,SFA)相对较低。SFA与MUFA的平均活化能最高,平均活化体积绝对值也处于较高水平,因此,SFA和MUFA的脂解速率常数对温度和压力的敏感性较高。基于Arrhenius方程和Eyring方程建立两个磷脂脂解动力学模型,两者具有良好的拟合度和相似的温度-压力等值线图。因此,磷脂中不同成分的脂解动力学不同,PL的脂解与PUFA的脂解更相似。基于本研究建立的动力学模型,通过预设的压力、温度和时间条件可以预测磷脂的脂解程度,从而设计或优化猪肉高压处理的加工工艺参数,提高肉制品品质。

In order to explore the effect of combined high-pressure and thermal treatment on the lipolysis of phospholipids in pork,the phospholipid degradation kinetics of pork was studied in the 300 to 700 MPa pressure range and in the 20 to 60℃temperature range.It was found that the lipolysis process followed first-order kinetics.The lipolysis rate constant(k)of polyunsaturated fatty acids(PUFA)was the highest,followed by total phospholipids(PL),and those of monounsaturated(MUFA)and saturated fatty acids(SFA)were relatively low.The average activation energies of SFA and MUFA were the highest,and the absolute values of the average activation volume were at a high level.Hence,the lipolysis rate constants of SFA and MUFA were sensitive to temperature and pressure.Kinetic models for PL lipolysis were established using the Arrhenius and Eyring equations.Both models had good fitness to the data and showed similar temperature-pressure contour curves.Accordingly,the lipolysis kinetics of different phospholipid components was different,but the lipolysis kinetics of PL was very similar to that of PUFA.The kinetic models could predict the degree of lipolysis of phospholipids under preset pressure,temperature and time conditions,which will be helpful in designing or optimizing high-pressure processing parameters to improve the quality of meat products.