Nondestructive Determination of Moisture Content in Dry Fruits by Impedance and Phase Angle Measurements  

作　　者：Chari V. Kandala Ron Holser Jaya Sundaram Naveen Puppala 

机构地区：[1]National Peanut Research Laboratory, USDA, Dawson, GA, USA [2]Russell Research Center, USDA, Athens, GA, USA [3]Faculty of Engineering, University of Georgia, Athens, GA, USA [4]Clovis Center, New Mexico State University, Clovis, NM, USA

出　　处：《Journal of Sensor Technology》2015年第4期73-80,共8页传感技术（英文）

摘　　要：An electronic method to estimate the moisture content (MC) of dry fruits by measuring the impedance (Z) and phase angle (θ) of a cylindrical parallel-plate capacitor with dry fruit sample between the plates, using a CI meter (Chari’s Impedance meter) at 1 and 9 MHz is described. Capacitance C was derived from Z and θ, and using the C, θ, and Z values of a set of dried cherries, whose MC values were later determined by the vacuum hot air-oven method, a calibration equation was developed. Using this equation, and their measured C, θ, and Z values, the MC of a group of cherries, not used in the calibration, was predicted. The predicted values were compared with their air-oven values. Similar predictions were done using the same method on dried blueberries. The method worked well with a good R2 value, and showed a low standard error of prediction (SEP) in the measured MC range between 5% and 30% for cherries, and 9% and 22% for blueberries.An electronic method to estimate the moisture content (MC) of dry fruits by measuring the impedance (Z) and phase angle (θ) of a cylindrical parallel-plate capacitor with dry fruit sample between the plates, using a CI meter (Chari’s Impedance meter) at 1 and 9 MHz is described. Capacitance C was derived from Z and θ, and using the C, θ, and Z values of a set of dried cherries, whose MC values were later determined by the vacuum hot air-oven method, a calibration equation was developed. Using this equation, and their measured C, θ, and Z values, the MC of a group of cherries, not used in the calibration, was predicted. The predicted values were compared with their air-oven values. Similar predictions were done using the same method on dried blueberries. The method worked well with a good R2 value, and showed a low standard error of prediction (SEP) in the measured MC range between 5% and 30% for cherries, and 9% and 22% for blueberries.

关 键 词：CHERRIES BLUEBERRIES CI Meter Moisture Content CAPACITANCE IMPEDANCE Dry FRUITS 

分 类 号：R73[医药卫生—肿瘤]