通过测量醋渍黄瓜的介电特性来衡量其品质并作为一种潜在的非损伤性评价手段。研究采用平行板电极测量了经过不同时间真空醋渍处理的黄瓜于100 kHz~12 MHz的介电特性，同时测量了反映醋渍黄瓜理化品质的参数，如酸度、盐度、亚硝酸盐含量、质构参数。研究结果表明，在整个频率区间，真空醋渍黄瓜的相对介电常数和介电损耗因子都随频率的增加而单调递减，真空醋渍时间与介电参数存在负相关关系。真空醋渍黄瓜的介电参数与盐分和亚硝酸盐含量存在着较好的相关性，然而介电参数与酸度、质构指标之间的相关性不明显。在2.26 MHz和12 MHz频率下，相对介电常数与盐分呈现出良好的线性关系，线性拟合方程的决定系数R2高达0.9813和0.9858；该研究为真空醋渍蔬菜快速检测仪器的开发提供了理论参考。

The traditional indicators of pickled cucumber for vacuum acetic impregnation include acidity, texture profile, salinity and nitrite content. The dielectric properties of vacuum impregnated pickled cucumber were measured at 100 kHz~12 MHz frequency range from different time using a fast nondestructive method with parallel-plate capacitor. The results showed that both dielectric constant and loss factor of vacuum-impregnated pickled cucumber decreased monotonically as frequency increased. Negative correlations between dielectric parameters and vacuum impregnated time were observed. Dielectric parameters presented positive correlations with salt and nitrite contents, but no obvious relationship were remarked with acidity and texture profile. At 2.26 MHz and 12 MHz, R2 of the linear regression equations for dielectric constant and salt content were 0.9813 and 0.9858, respectively. Dielectric measurement provided new information concerning pickled vegetables for vacuum impregnation.

“十二五”科技支撑计划（2012BAD37B01）