Department of Post Harvest Process & Food Engineering, College of Agriculture, Jawaharlal Nehru Krishi Vishwa Vidyalaya, Jabalpur-482004
Online published on 18 February, 2020.
In the present study, grapes pretreated with different concentrations of potassium carbonates plus olive oil and soy lecithin with different dipping times. Adryer was built to perform the experiment under controlled condition of drying air at temperature 50°C and velocity 1.0 m/s. Grapes dipped into 1% olive oil plus 6% K2CO3 emulsion, at 50°C for 2 min. prior to drying showed shorter drying times and comparatively good quality raisin, whereas grapes dipped into 1.5% soy lecithin, at same conditions resulted in a total drying time slightly higher than the most effective pre treatment. The drying rates of grapes were modeled by the page equations. Grapes that are naturally dried usually darken in colour, whereas dipped grapes stay yellow-green.
