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The adsorption characteristics of coffee were imestyated at 5, 15, 25 and 35℃ under various water activities such as 11, 32, 57, 73 and 90% and prediction models were developed by optimization program. The moisture adsorption isotherm curves were similar to the typical sigmoid type. The values of equilibrium moisture content and the monolayer moisture content were highest in the Freeze Dried, which was due to porous structure by the drying method. In the result of adjusting the isotherm models in this paper, Halsey model generally gave the best tit for isotherms of coffee. Prediction model for equilibrium moisture content was established with water activity and temperature. Adsorption prediction models were also developed with water activity, with water activity and time. and with water activity, time and temperature, respectively.
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