Electrohydrodynamic (EHD) Drying of Grape Pomace

Abstract

The objective of this research was to find the industrially-accepted processing method of the currently underutilized wet grape pomace prior to subsequent extraction of natural ingredients. Due to high moisture content (2.5-3.0 kg/kg db), thermal drying of pomace is an expensive and time-consuming operation. Therefore, the energy efficiency of non-thermal electrohydrodynamic (EHD) technology as applied for grape pomace drying was extensively studied. The experiments on EHD drying at temperature 20℃ revealed excellent quality of the dry product. Superior energy efficiency of the EHD drying ranging from 600 to 1580 kJ per kg of evaporated water as reported in topical literature was confirmed in our experimental study. These preliminary experiments on the lab-scale showed benefits of EHD drying of heat-sensitive grape pomace to be further transformed into food additives, skin powder and grape oil.