Drying behaviour of rapeseed under thin layer conditions.

Thin layer drying behaviour of rapeseed (toria, Brassica campestris) varieties like 'TL-15', 'TH-68' and 'Sangam' in the temperature range of 30 to 70°C and at constant air velocity of 2 m/sec was studied. The validity of modified Page's equation for prediction of drying time was assessed by fitting the experimental drying data. The drying air temperature affected drying time significantly. The effect of variety on drying time was not significant. Drying constants of modified Page's model were calculated for each variety and at each drying temperature. Germination percentage and seed vigour index were not affected significantly when dried up to 55°C and reduced drastically to 16 to 20% when dried above 55°C.