Effect of Ohmic Heating on Quality and Recovery of Oil from Mustard Seed

Abstract

The effects of process parameters on ohmic heating (electric field strength of 600 V.m-1, 750 V.m-1 and 900 V.m-1), end point temperature (70 ºC, 80 ºC and 90 ºC) and holding time (5 min, 10 min and 15 min) were investigated on oil recovery from mustard seeds using laboratory model ohmic heating system. Primary quality attributes viz. free fatty acids and colour value of oil from ohmically treated mustard seeds was determined using standard methods. The maximum oil recovery (84.90 %) was obtained when the sample was heated at 90 oC using electric field strength of 750 V.m-1 for a holding time of 15 min. The free fatty acid (1.11 % to 1.27 %) in the oil samples was within the acceptable limit (0.5-3.0 %). The L value of oil extracted from ohmic heated mustard seeds ranged from 40.32 to 40.87 as against 40.71 of control sample.