Quality characteristics of caper seed oils—The impact of extraction: Soxhlet versus cold pressing

Caper seed oil obtained by the soxhlet extraction had significantly (p < .05) higher acidity, peroxide content, viscosity, unsaponifiable matter, total phenolics, and antioxidant values than those of oils extracted by the cold-press for all tested varieties. Cold-pressed oil had significantly (p < .05) higher iodine and saponification values compared to oil extracted by the Soxhlet system. The oil obtained by cold-press resulted in higher fatty acid levels for all samples as compared to Soxhlet extracts. The tocopherol contents of the oils extracted by cold pressing were higher than those of Soxhlet extracts, except γ-tocopherol, which was significantly (p < .05) higher in the Soxhlet-extracted oils for Capparis spinosa. For all varieties, the level of phenolic compounds was significantly (p < .05) reduced when the oil was extracted by the cold-pressing system. In general and regardless of the extraction system, the type of variety was found to have a significant effect on all parameters measured. Practical applications Caper plant grows at the most countries of Africa, Asia, and South European. Capers have very important roles for beneficial natural components in the food industry. Capers have very important roles for beneficial natural components in the food industry. There are a significant increase in the interest of bioactive compounds from plant products. Cold-pressing procedure involves no heat or chemical treatments. Cold-press technique is simple and environment-friendly method. Solvent extraction, on the contrary, is a cost-effective and fast method of oil extraction.