Equilibrium moisture content isotherm characteristics of rapeseed

Le Anh Duc, Keum Dong Hyuk


The ERH and EMC of rapeseed were determined using static method with a constant environment chamber for various combinations of air temperature and relative humidity. The moisture desorption isotherm data are used to determine EMC equation. Four EMC/ERH equations are recommended as the best predictions of equilibrium moisture content for grains and oilseeds over wide ranges of temperatures and relative humidity was used: the Chung-Pfost, modified Halsey, modified Henderson, and modified Oswin, and their estimated parameter were evaluated for goodness of fit. The Modified Halsey equation is identified as the best adequate equation for prediting desorption EMC isotherm of rapeseed. The RMSE for ERH and EMC is 1.909% and 0.281%. The R2 for ERH and EMC is 0.9936 and 0.9925, respectively.    The modified Oswin equation is fairly good fits, and the Chung-Pfost and modified Henderson equation could not available for prediction EMC of rapeseed.

Keywordsrapeseed, equilibrium moisture content, isotherm, temperature, saturated salt


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