【摘要】 为了弄清食品在超高静压下的压致升温情况,以便准确控制杀菌的加工工艺条件,本文测定了较小热损失条件下(利用聚四氟乙烯套筒模拟)食品及其成分的压致升温值并提出了预测某一食品压致升温值的方法,与实测值比较可知此方法能较好地预测其压致升温值;由热力学第一定律推导出一定压力和温度范围内某一食品的压致升温值主要取决于其初始温度和压力,并通过经验方程拟合食品的压致升温值,建立了食品压致升温值与压力和初始温度之间的关系。在100~400 MPa下温度25~55℃时较小热损失条件下对水、大豆油和橄榄油的压致升温值进行拟合,结果表明,对这三种物质拟合得到方程的回归系数依次分别为0.976、0.990和0.981,此外,将实测值和用方程拟合得到的预测值进行比较,相对误差均不超过5%,说明此方程的拟合效果较好。更多还原

【Abstract】 In this study, we aimed to predict the behavior of foods during compression heating using ultra-high hydrostatic pressure and to accurately control processing conditions for sterilization. The compression heating values of food and their components under low heat loss(simulated with a Teflon sleeve) were measured and a method to predict the compression heating value for a particular food item was proposed. A comparison of the estimated and measured values showed that this method could accurately predict compression heating values of food. Within a certain range of pressure and temperature, the compression heating value of food could be determined using the initial temperature and pressure, as derived from the first law of thermodynamics. The fitted compression heating value was obtained from an empirical equation, and the relationship between compression heating values of food and initial pressure/temperature was established. The compression heating values of water, soybean oil, and olive oil were determined under the lower heat loss of 100~400 MPa and 22~55 ℃. The results showed that the three regression coefficients(R2) obtained by applying the regression equation were 0.976, 0.990, and 0.981, respectively. In addition, the measured value was compared with the value predicted using the equation and the relative errors were found to be less than 5%. This finding indicates that this equation provides a valid prediction.更多还原