Evaluation of calibration of moisture meter for Indian wheat by microwave oven drying technique and commercial moisture meter

Abstract

Moisture plays an important role in storage and processing of food grains, cereals and other agricultural products. It is the single most important characteristics of most agricultural products with respect to quality maintenance. This paper describes how to prepare samples for moisture determination, and calibrate a moisture meter for a particular grain. Calibration of a laboratory-developed moisture meter (LDMM) with a a commercial moisture meter (CMM) is also presented in this paper, in order to evaluate its performance. It shows that the values estimated by the LDMM were in good agreement with the moisture content values that are obtained by CMM, and the developed meter has a less than ± 1% error. It also describes the studies carried out for calibration of the LDMM using a microwave oven drying technique. An evaluation of the calibration performance of LDMM with two different techniques has also been reported. The microwave oven method and dry oven method have been compared for moisture determination of Indian wheat. It has been observed that the microwave method took 10–20 min compared with 18–20 h by the standard dry oven method for moisture determination of Indian wheat. The results obtained by the microwave oven method were compared with those obtained by the dry oven method. No statistical difference was observed between the percentage moisture values of Indian wheat samples by microwave drying and dry oven drying. The accuracy of the developed meter has also been tested by taking different numbers of calibration samples. It was observed that the accuracy increased considerably with an increase in the number of calibration samples.