摘要
该试验主要分析了南疆红枣介电特性参数在干燥过程中的变化,研究在不同射电频率下(0.1、1、10、40、100 kHz)样品经过不同干燥温度(55、60、65℃)处理后的品质因数和正切值与介电参数的关系。结果表明,当干燥温度为65℃时,介电参数ZD变化趋势最明显,变化幅度最大。且无论哪一个干燥温度,在含水率为50%时,ZD都达到最大值。干燥温度为65℃时,在不同频率下红枣的复阻抗的实部ZD、虚部ZQ与电感LQ变化趋势一致,且频率越低,变化幅越度越大。考虑到每个个体样品的质量都不相同,特引入了单重品质因数和单重正切值作为评价红枣介电参数变化的新指标,湿基含水率与单重正切值、单重品质因数的关系,在含水率为60%~50%时,达到最大值。
The test mainly analyzed the change of the dielectric properties of the jujube in South Xinjiang during the drying process. The study handled jujube by different drying temperatures(55, 60, 65 ℃) at the radio frequency(0.1, 1, 10, 40, 100 kHz). The relationship between the figure of merit and the tangent and the dielectric parameters were studied. The results showed, the dielectric parameter ZD had the most obvious change trend and the largest change when the drying temperture was 65 ℃. Regardless of drying temperatures, the maximum value was reached at a moisture content of 50%. When the drying temperature was 65 ℃, the real ZD, imaginary part ZQ and inductance LQ of the complex impedance of red jujube are consistent at different frequencies, and the lower the frequency, the greater the variation. Considering the different weight of each individual sample, a single quality factor and a single weight tangent value were introduced as new indicators for evaluating the change of dielectric parameters of jujube. The relationship between wet basis moisture content and single tangent value, single weight quality factor reached a maximum at a water content of 60% to 50%.
作者
李光辉
弋晓康
谭进涛
LI Guanghui;YI Xiaokang;TAN Jintao(Key Laboratory of Modern Agricultural Engineering,College of Mechanical and Electrical Engineering,Tarim University,Alar 843300)
出处
《食品科技》
CAS
北大核心
2019年第11期73-77,共5页
Food Science and Technology
基金
国家自然基金项目(31260288)
关键词
红枣
干燥
无损检测
介电参数
red dates
drying
nondestructive testing
dielectric parameters
