Vol. 12, Issue 4 (2023)

Author(s):
E Jayashree

Abstract:
The sun drying characteristics of two varieties of black pepper viz. Sreekara and Panniyur-1 was studied. The drying process took place in the falling rate period. Sreekara took 38 h to dry from initial moisture content of 244.82% dry basis (d.b.) to the final moisture content of around 9.77% d.b. Whereas Panniyur-1 took 40 h to dry from initial moisture content of around 270.37 % d.b. to the final moisture content of around 9.63% d.b. The drying data were fitted to eight different mathematical models. The performance of these models was investigated by comparing the coefficient of determination (r²), root mean square error (RMSE), mean bias error (MBE) and mean square of deviation (2) between the observed and predicted moisture ratios. Among the models, the diffusion approximation model was found most suitable to explain the thin layer open sun drying behaviour of black pepper. The effective moisture diffusivity during drying of black pepper was 4.13 x 10^-07 m²s^-1 for Sreekara and 4.90 x 10^-07 m²s^-1 for Panniyur-1.