MICROWAVE DRYING CHARACTERISTICS OF ASSAM CTC TEA (CAMELLIA ASSAMICA)

ABSTRACT Microwave drying characteristics of Assam crush, tear, curl (CTC) tea were determined at five different microwave power of 180, 360, 540, 720 and 900 W respectively. The effect of power level on moisture content and drying rate (d.b.) of 50 g CTC tea sample were investigated. The time required to reduce the moisture content to any given level in microwave drying was dependent on the power level. Four mathematical models (Henderson and Pabis, Lewis, Page and logarithmic) were used for fitting experimental data. The estimated empirical parameters together with the corresponding sum of square error from nonlinear regression analysis for all the models were tested. The Page model was found to have the better suitability for describing drying characteristics of Assam CTC tea. PRACTICAL APPLICATIONS Assam crush, tear, curl tea is an important process food commodity involving substantial commercial activities at national as well as international levels. Appropriate processing of this commercially important commodity is a critical issue to be addressed to fetch higher prices at competitive tea markets. The major disadvantages of present conventional dryers used in tea drying are low-energy efficiency and long drying time. But reduction in time and energy consumption by using microwave in tea drying could make a significant contribution to tea industry. This study may successfully used for design, analysis and performance evolution of microwave tea drying.