Optimization of organogels prepared with turpentine oil and wax mixtures via response surface methodology and determination of vaporization kinetic parameters

BACKGROUNDThe main aim of the study is to investigate the thermal, textural and vaporization behaviors of turpentine oil (representing essential oils) organogels prepared with wax mixtures (beeswax, BW; shellac wax, SHW) instead of a single wax. The second aim was to determine the optimum level of wax addition to minimize vaporization of volatiles using response surface methodology.RESULTSBoth weighing and thermogravimetric analyses showed that when the total wax concentration increased, the vaporization was decelerated. The variation of the hardness and melting point values depended on both wax types and amounts in the mixtures. Additionally, the kinetics of the vaporization of the volatile compounds at 37 degrees C were evaluated, and both first- and second-order reaction kinetic models fitted well for the vaporization with R2 values of 0.96-0.99. The organogelation increased the thermal stability and limited the release of volatiles. The multiple response optimization results showed that the melting point, the reaction rate constant and the weight loss of the organogels produced with 24.43% BW and 17.68% SHW were 44.40 degrees C, 4.00 x 10-3 day-1 and 30.02%, respectively.CONCLUSIONAs a result, essential oil organogels produced with a wax mixture instead of a single wax can provide controlled release of volatiles as well as tailored texture and melting range. (c) 2024 Society of Chemical Industry.