Air diffusion of aroma-active components from crude citrus essential oils and their extract phases obtained by solvent extraction

Citrus essential oils' (CEOs') quality has been enhanced by solvent extraction, aiming at both the recovery of extract phases enriched on oxygenated compounds and maintenance of the typical citrus aroma. The air diffusion of aroma-active compounds found in crude CEOs, orange and acid lime, and their extract phases obtained by liquid-liquid extraction using hydroalcoholic solvents were thus evaluated. Experimental assays were conducted in a diffusion tube, where lower odor intensities were related to longer distances from the liquid mixture. Terpenes were mainly responsible for crude CEOs and orange extract phase aroma due to their high concentration in the vapor phase, while citral exhibited higher odor intensity in a region close to the acid lime extract phase. Finally, diffusion profiles simulated by COMSOL software fit well with those experimentally obtained, mainly for terpenes from crude CEOs.