Abstract: This study aimed to comparatively analyze physiochemical properties, fatty acid composition, VE content and oxidative stability of Carya cathayensis Sarg. oils extracted by cold pressing, supercritical carbon dioxide extraction and organic solvent extraction. They showed considerable variations in acid value, peroxide value, moisture and volatile contents and color but only slight variations in characteristic indices such as iodine value, saponification value, refractive index, relative density were observed. Moreover, these samples had nearly identical fatty acid composition; unsaturated fatty acids were predominant and revealed the highest relative content in the seed oil obtained by supercritical carbon dioxide extraction. The seed oil obtained by organic solvent extraction revealed the highest total VE content, among which, α-vitamin E was predominant. In addition, the seed oils obtained by different extraction techniques exhibited a significant variation in their oxidative stability and the one obtained by organic solvent extraction had the best oxidative stability. In conclusion, cold pressing is the most suitable extraction technique for the extraction of Carya cathayensis Sarg. oil.

Key words: Carya cathayensis Sarg., extraction technique, physicochemical indexed, fatty acid, vitamin E, oxidative stability