Drying Kinetics of Pear Slices in Greenhouse Solar Dryer

An experimental study was performed to determine the drying characteristics of pear using greenhouse based solar dryer and under open sun with natural convection. Prior to drying, sliced pear samples were pre-treated: i) control inside dryer i.e. with no dip, ii) blanching, iii) soaking in 2% KMS (Potassium Metabisulphite) solution, iv) blanching and soaking in 1% KMS solution, v) control outside dryer i.e. with no dip. The experimental drying data of pear were fitted to five different mathematical models viz. Exponential, Generalized exponential, Page’s, Logarithmic and Power law models, and drying rate constants and coefficient of models tested were determined by non-linear regression analysis. Among the various models tested to interpret the drying behaviour of pear, Page’s model was selected which gave best statistical indices of coefficient of determination (R2) and standard error of estimation (SEE) values.