Process kinetics optimization for extraction of essential oil from the peel of Citrus sinensis for the development of food packaging film

The goals of the present work were to achieve maximum extraction efficiency from Citrus sinensis peel and effective utilization of its bioactive compounds. This work focused on studying the physicochemical characteristics and yield percentage of citrus essential oil (CEO) extracted from citrus peels at different extraction times, extraction temperatures, solid-liquid ratios, and solvent combinations, and the data of yield percentage was subjected to find the best kinetic model for better yield. C. sinensis peel powder was subjected to Soxhlet extraction of essential oil at varied solid:liquid ratios (1/2, 1/4, 1/6, 1/8, and 1/10), time intervals in minutes (120, 150, 180, 210, 240, 270, and 280), temperatures (50, 60, 70, 80, 90, and 100degree celsius), and solvents (n-hexane, petroleum ether, chloroform, methanol, and water) to characterize their impact on yield percentage. The essential oil extraction kinetics were assessed using the experimental data and two different kinetic models (zero-order and first-order kinetic model). The bioactive compounds were assessed using GC-MS, as well. Amongst the other solvents, maximum extraction yield was observed at 90degree celsius for 270 min using n-hexane. GC-MS results showed that d-limonene was the predominant compound constituting 41.41%. A good agreement between applied kinetic models and experimental data was demonstrated by the first-order model (R-2 = .9830) and the zero-order kinetic model (R-2 = .9719). Thus, the effective conditions for maximum extraction yield of CEO peels were optimized and the extracted CEO can be used in food packaging applications for shelf-life extension.