Use of Temperature and Humidity Sensors to Determine Moisture Content of Oolong Tea

Sensors

Andrew Chen²  Hsuan-Yu Chen¹ 

[1] Department of Materials Science and Engineering, National ChungHsing University, Taichung 40227, Taiwan; E-Mail:;Department of Electrical Engineering, National Taiwan University, Taipei 10617, Taiwan; E-Mail:

关键词: moisture measurement;    tea leaves;    equilibrium moisture content;    equilibrium relative humidity;    uncertainty analysis;   

DOI  :  10.3390/s140815593

来源: mdpi

【 摘 要 】

The measurement of tea moisture content is important for processing and storing tea. The moisture content of tea affects the quality and durability of the product. Some electrical devices have been proposed to measure the moisture content of tea leaves but are not practical. Their performance is influenced by material density and packing. The official oven method is time-consuming. In this study, the moisture content of Oolong tea was measured by the equilibrium relative humidity technique. The equilibrium relative humidity, and temperature, of tea materials were measured by using temperature and relative humidity sensors. Sensors were calibrated, and calibration equations were established to improve accuracy. The moisture content was calculated by using an equilibrium moisture content model. The error of the moisture content determined with this method was within 0.5% w.b. at moisture <15% w.b. Uncertainty analysis revealed that the performance of the humidity sensor had a significant effect on the accuracy of moisture determination.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.