3.40 fl oz - ZIN: 428135 - Grape Seed Oil . ( Vit is vinifera ). The oil is heat extracted from the seeds of the fruit. Unfortunately it is unavailable in its natural state, for unrefined grapeseed oil is considered to be unpalatable - certainly it has an objectionable odour. The refined oil has an attractive green tint and an exceptionally fine texture. It is also virtually odourless, hence its popularity with those aromatherapists who prefer to use bland base oils. Percentage in Blends: Can be used as a base oil, 100 per cent, though many aromatherapists prefer to add at least 10 per cent of an unrefined oil, such as sunflower seed or hazelnut, to increase its vitamin content.