Oil was extracted from the seed of white-flesh (Hylocereus undatus; WFSO) and red-flesh (Hylocereus polyrhizus; RFSO) dragon fruits using a cold extraction process with petroleum ether. The delta-, gamma-, and alpha-tocopherol content, fatty acid and triacylglycerol composition, thermal and rheological properties of the extracted dragon fruit seed oils were analysed. The results showed that the dragon fruit seeds contained a high amount of oil up to 34.13%. The principal tocopherol in WFSO and RFSO was alpha-tocopherol. The total tocopherols content of RFSO was 1.6 times higher than that of WFSO. The three main fatty acids in these oils were palmitic acid (C16:0), oleic acid (C18:1) and linoleic acid (C18:2). The seed oil is interesting from a nutritional point of view: the essential fatty acid content of WFSO and RFSO counts up to 55.64% and 45.37% respectively. The main triacylglycerol in WFSO and RFSO was LLL, LLO, PLL, LOO and PLO. The thermal curves for WFSO and RFSO consisted of two main endothermic peaks with a broader temperature range around these peaks of -49.58 and 3.41 °C. The apparent viscosity of WFSO and RFSO was similar (14.24-14.32 mPa.s). Thus the dragon fruit seed oils can be considered as a new source of tocopherols and essential fatty acids
