Encapsulation of Orange Peel Oil in Biopolymeric Nanocomposites to Control Its Release under Different Conditions

Orange peel oil (OPO) is one of the most common flavorings used in the food industry, but it is volatile under environmental conditions (the presence of light, oxygen, humidity, and high temperatures). Encapsulation by biopolymer nanocomposites is a suitable and novel strategy to improve the bioavailability and stability of OPO and its controlled release. In this study, we investigated the release profile of OPO from freeze-dried optimized nanocomposite powders as a function of pH (3, 7, 11) and temperature (30, 60, and 90 °C), and within a simulated salivary system. Finally, its release kinetics modelling was performed using experimental models. The encapsulation efficiency of OPO within the powders, along with the morphology and size of the particles, were also evaluated by an atomic force microscopy (AFM) analysis. The results showed that the encapsulation efficiency was in the range of 70-88%, and the nanoscale size of the particles was confirmed by AFM. The release profile showed that the lowest and the highest release rates were observed at the temperatures of 30 and 90 °C and in the pH values of 3 and 11, respectively, for all three samples. The Higuchi model provided the best model fitting of the experimental data for the OPO release of all the samples. In general, the OPO encapsulates prepared in this study showed promising characteristics for food flavoring applications. These results suggest that the encapsulation of OPO may be useful for controlling its flavor release under different conditions and during cooking.