Simultaneous extraction of edible oil from avocado and capsanthin from red bell pepper using supercritical carbon dioxide as solvent

Abstract

Crude avocado oil is similar to olive oil and contains health-beneficial compounds such as tocopherols and phytosterols. Capsanthin is the major carotenoid present in the red bell pepper (Capsicum annuum L.) and is used as a natural food colorant with biological activity. In order to combine the benefits of both and to produce capsanthin-rich avocado oil using a clean extraction technology, freeze-dried avocado and red bell pepper pulps were separately packaged in a single fixed bed extractor, in which supercritical carbon dioxide (scCO2) was passed through the bed at 50°C and 400bar. The target compounds were simultaneously extracted from both sources, the first source containing lipids and the second source rich in capsanthin. The scCO2 passed first through the avocado pulp containing 68% lipids, and then that were passed through the red bell pepper pulp contained 625μg/g capsanthin. Lipids extracted in the first bed served as co-solvent with CO2 in the extraction of capsanthin in the second bed. An extract consisting of intensely red-colored oil containing 280–460μg/g capsanthin was obtained. In the process, around 88% avocado oil and from 30% to 50% capsanthin from red bell pepper were extracted. The pepper pulp extraction without using oil as a co-solvent resulted in 1% yield of a concentrated extract containing 11,000μg capsanthin per gram extract, but with only 15% recovery, corresponding to the extraction of 100μg capsanthin from a total of 625μg capsanthin per gram of freeze-dried red bell pepper.