Over the last few years, the fractionation of orange peel oil through the use of supercritical fl uid carbon dioxide (SCFCO2) has been a matter of intense research. Despite this fact, the deterpenation of such material has still been conducted in several industries by means of vacuum distillation. In this work we present results using an automatic vacuum distillation column operated in the semi-batch mode over the temperature range of 50°-80°C, from 10 to 30 mbar and with a refl ux ratio of 0.25 and 0.75. As in the case of vacuum distillation, an experimental design was adopted to perform the extractions using SCCO2 in a high-pressure column operated in the countercurrent mode in the range of 50°-70°C, from 70-100 atm and with a solvent to oil mass ratio up to 60. Phase equilibrium data for the system CO2- orange peel oil, which are essential for the high-pressure fractionation, are provided in a wide range of temperature and pressure. The results of orange peel oil fractionation are presented and analyzed with regard to the content of oxygenated compounds and sensory analysis.
Introduction Citrus oil is a mixture of high volatile components such as mono- and sesquiterpene hydrocarbons, oxygenated compounds and non-volatiles such as pigments and waxes. In spite of the high content, the monoterpene hydrocarbons, they do not contribute much to the fl avor or fragrance of the oil. Because they are unstable to heat and light, monoterpene hydrocarbons must be removed to stabilize the oil. The odoriferous of a citrus oil consists of alcohols, aldehydes and ketones that provide much of its characteristic flavor.
In the past few years, citrus oil fractionation has received an increased attention due to the direct application of folded and terpeneless oils in the food and pharmaceutical industries. The fractionation of these oils has been commonly performed using conventional techniques, such as vacuum distillation. Unfortunately little information on this subject is available in the open literature.