Assessment of subcritical propane, ultrasound-assisted and Soxhlet extraction of oil from sweet passion fruit (Passiflora alata Curtis) seeds

Abstract

This study reports the results of subcritical propane (SubFE), ultrassound-assisted and Soxhlet extraction of sweet passion fruit (Passiflora alata Curtis) seed oil cultivated under organic system in terms of extraction yield, refractive index, density, acid value, fatty acid composition, tocopherol content, antioxidant activity and oxidative stability. SubFE higher extraction yield (23.68%) was obtained at 60°C/2MPa with an extraction efficiency of 84% compared to Soxhlet extraction using n-hexane. Major values of unsaturated fatty acids were obtained by SubFE at 60°C/2MPa (86.36%). Samples obtained by Soxhlet extraction using n-hexane and SubFE at 60°C/2MPa showed higher tocopherols contents. Thermogravimetric analysis indicated a high resistance to oxidation for all extraction methods evaluated. Therefore, the results obtained demonstrated that the oil obtained can be considered as new sources of natural antioxidant and it has a potential as a raw material for edible products, chemical and pharmaceutical industries.