Received: 29-06-2023 / Accepted: 05-01-2024
The objective of this study was to determine the optimal conditions for oil and piceatannol extraction from passion fruit seeds. Oil was extracted by dynamic extraction and piceatannol extraction was optimised by response surface methodology. The piceatannol content was analysed by high performance liquid chromatography. Results showed that the best oil extraction conditions were as follows: ethyl acetate used as extraction solvent, temperature of 30C, extraction time of 30 minutes and two times of extraction (with material/solvent ratio of 1/10 and 1/5 (w/v) for the first and the second times, respectively). At these conditions, the oil extraction yield was of 78.12 ± 0.31%. The crude oil had acid value of 1.61 ± 0.05mg KOH/g and peroxide value of 0.62 ± 0.03 meq O2/kg. These values were lower than the maximal legal levels specified in TCVN 7597:2018 Vietnamese standard for vegetable oils. Piceatannol content in defatted passion seeds corresponded to 68.94% of initial piceatannol quantity of passion fruit seeds. A second-order polynomial model with three important variables (ethanol concentration, temperature and extraction time) was successfully built to describe the piceatannol extraction (R2 = 0.9635). The optimised conditions were the followings: 68% ethanol (v/v), at 85C during 45 min. This research could serve as bases for full exploitation of passion fruit seeds, producing by-products utilised in cosmetic and food technologies.