【摘要】 采用同轴探针方法分别测定了30-80℃,频率:320-2960 MHz内罗非鱼鱼糜和阿拉斯加狭鳕鱼糜的介电常数和介电损失率。频率一定时,两种鱼糜的介电常数随温度升高而降低;在相同的温度下,频率增加,鱼糜的介电常数反而减小。频率升高使两种鱼糜的介电损失率先减少后增加,分别在890 MHz(罗非鱼鱼糜)和1350MHz(狭鳕鱼糜)出现拐点。温度与介电损失率的相关性与频率有关,拐点频率之前,温度与介电损失率成正相关性,而大于拐点频率时,则成负相关性。本研究提出了两种鱼糜的介电常数和介电损失率关于温度和频率的预测方程,预测值与实验值具有良好的一致性。两种鱼糜的穿透深度在915 MHz随温度升高而减小,在2450MHz时则正好相反。鱼种的差异对鱼糜介电特性和穿透深度有较大影响。SPSS软件可以对鱼糜的介电特性进行有效预测。更多还原

【Abstract】 The dielectric constant and loss factor of tilapia surimi and Alaska pollack surimi were measured by the open-ended coaxial probe method in the frequency range from 320 MHz to 2 960 MHz and temperature from 30℃ to 80℃. Dielectric constant of the two kinds of surimi decreased with both temperature and frequency. The dielectric loss factor changed quadrically with increasing frequency: first decreasing and then increasing. The loss factor of tilapia surimi and Alaska pollack surimi dropped to their minimums at 890 MHz and 1 350 MHz respectively. Temperature had a positive correlation with the loss factor before the inflexion and the temperature dependence reversed after the inflexion frequency. Six predictive equations related to the dielectric properties of the two kinds of surimi were developed as a function of temperature and frequency, and then proved to be reasonable. The penetration depths decreased with increasing temperature at 915 MHz, but the temperature dependence reversed at 2 450 MHz. The differences between surimi species had a significant effect on the dielectric properties and penetration depths of surimi. It was effective to apply SPSS to the prediction of surimi dielectric properties.更多还原