Enzyme-mediated extraction of limonene, linalool and linalyl acetate from bergamot peel oil by pervaporation

Bergamot peel oil is highly attractive for food and pharmaceutical industries due to its content of valuable essential oil, which is enriched with high-added valuable compounds, such as limonene, linalool and linalyl acetate. Nevertheless, there are some limitations for the separation of such compounds. In this framework, pervaporation (PV) technology was proposed as a tool for the separation of limonene, linalool, and linalyl acetate from bergamot oil by using two different commercial organophilic membranes (PDMS-1070 and POMS-PEI). The use of an enzymatic pre-treatment was also investigated in order to enhance the performance of selected membranes. All PV experiments were carried out at different temperatures (ranging from 25-40 ºC) in order to analyze the temperature dependence by the Arrhenius relationship. Experimental data indicated that both investigated membranes did not present significant differences in terms of enrichment factor, independently from the enzymatic pre-treatment (at 25 ºC). However, the enrichment factors increased significantly at 40°C when enzymes were applied. The experimental results clearly indicate that PV is a viable approach for the recovery of such aroma solutes from bergamot peel oils as it yields good separations under mild operating conditions. The efficiency of the pervaporative process is indeed enhanced if assisted by an enzymatic treatment.