Effect of nitrogen treatment on quality of cold pressed walnut oil

Abstract

In this work nitrogen treatment experiment was set up to determine the intensity of oxidation products accumulation in cold pressed walnut oil. The influence of the nitrogen treatment was assessed by measuring the primary and secondary oxidation products in oil samples immediately after treatment up to the 30 weeks of storage. Primary oxidation products of walnut oil samples were evaluated by measuring peroxide value and conjugated dienes content. Secondary oxidation products of walnut oil samples were evaluated by measuring p-anisidine value and 2-thiobarbituric acid value. These data should help us to describe oxidation mechanism of walnut oil and to recommend optimal conditions for walnut oil stabilization. However it is necessary to note that these data are not enough to make a final conclusion about the behavior of walnut oil after nitrogen treatment during storage. Currently we obtained preliminary data about accumulation of primary and secondary oxidation products in walnut oil.