Concentrating grape juice - by reverse osmosis pref using membrane having greater permeability for organic acids than for sugar

摘要

Grape juice for wine prodn. is concd. by reverse osmosis, pref. after pretreatment by filtration and/or centrifuging and opt. by pasteurising and/or treatment with pectase. Sugar concn. is increased without impairing grape juice quality, heat-caused irreversible changes are prevented, and quality can be improved by removing part of acid with the water.