Prediction of flavor characteristics of the phases from citrus essential oils fractionation using ethanol and water mixtures as solvents

Abstract

Essential oils are the main raw materials of fragrances and flavor industries. The citrus fragrances are the most used fragrances for the formulation of unisex perfumes for the producer and supplier market of perfumes, cosmetics and toiletries. Moreover, most of the main fragrances companies have citrus products in their portfolio. In 2014, in the export trade of perfumery and colonies, Brazil ranked as the 7th largest exporter and the 8th with more value sales, with values far below from France, the largest exporter market. Citrus essential oils are liquid products obtained generally by citrus fruit peel cold pressing and consist mainly of terpene hydrocarbons (from 60 to 98%) and their oxygenated derivatives. The terpene hydrocarbons are more susceptible to degradation and oxidation reactions when exposed to air and light, what can result in significant changes in the oil original flavor. The oxygenated compounds are the greatest responsible for the typical aroma of citrus fruit, which makes their content a high impact parameter in the set of the essential oil commercial value. Fractionation processes consisting of the concentration of oxygenates are largely developed in order to improve the sensorial quality of essential oils. Among them, the liquid-liquid extraction is offered as an interesting alternative process, since it can be carried out under ambient temperature and pressure conditions with, consequently, a low impact in the sensorial characteristics of the essential oil and low energy consumption. However, up to date, the study of different essential oils fractionation are mostly concentrated in obtaining quantitative information, such as phase equilibrium data and thermodynamic modeling. Therefore, obtaining qualitative data by the evaluation of the flavoring characteristics of the phases from the liquid-liquid equilibrium is of great interest to the area. The development of the proposed project will allow a further study about the citrus essential oil fractionation, with regard to sensorial properties (smell/ flavor) of terpene-rich and solvent-rich phases from the phase equilibrium of real systems composed of crude citrus essential oil (lime or orange), ethanol and water, at 298.2 K. It will be possible to relate the liquid-liquid extraction technique with the changes, and possible improvements, of flavoring characteristics of the phases from the liquid-liquid equilibrium through qualitative data, using the tools developed by the Laboratory of Separation and Reaction Engineering team, from Faculty of Engineering, University of Porto, in Portugal, such as Perfumery Ternary Diagrams and Perfumery Radars. (AU)