Comparative extraction of bioactive-rich oils from Chilean grape seeds and pomace using conventional and supercritical CO₂ technologies

Toloza-Mora M.; Bastías-Montes J.M.; Ortiz-Viedma J.; Vidal-San Martín C.; Jara-Quijada E.; Fraquela-Meissimilly H.; Muñoz-Fariña O.; Quevedo-León R.; Cabrera-Pérez M.; Ponce-Amasifuen G.; Tamarit-Pino Y. · Applied Food Research (2026) · DOI: 10.1016/j.afres.2026.102599

Resumen

The valorization of winery by-products through sustainable extraction technologies represents a promising strategy for developing high-value functional ingredients within the circular bioeconomy. This study evaluated the effects of extraction method (Soxhlet, Bligh and Dyer and supercritical CO₂ extraction, SFE) and grape-derived matrix (grape seeds and pomace, Vitis vinifera L.) on oil quality using a 3 × 2 factorial design. Extraction yield, antioxidant capacity (DPPH and ORAC), total phenolic content, physicochemical quality, fatty acid profile, FTIR spectroscopy, principal component analysis (PCA), and multi-response desirability analysis were used to identify the optimal extraction strategy. Soxhlet extraction produced the highest oil yields (15.6% for grape seeds and 11.4% for grape pomace), whereas SFE generated oils with superior functional quality. Grape seed oils obtained by SFE exhibited the highest antioxidant capacity (418.64 µg TE/mL by DPPH and 12,690.35 µM TE/mL by ORAC), the highest total phenolic content (24.18 mg CAE/g), the highest iodine value (152.0 g I₂/100 g), and the lowest peroxide value (2.0 meq O₂/kg). Two-way factorial ANOVA showed that both extraction method and grape matrix significantly affected oil quality, with significant interaction effects for ORAC, total phenolic content, acidity index, refractive index, and linoleic acid content (p ' 0.05). This study provides practical insights into the selection of extraction technologies for grape by-product valorization, highlighting SFE as an effective green alternative for obtaining high-quality functional oils, while also emphasizing the importance of balancing process efficiency, product quality, and potential scalability in applied food systems.

Instituciones: Universidad Nacional del Santa