Microencapsulation of citral with Arabic gum and sodium alginate for the control of Fusarium pseudocircinatum in bananas

Citral is an essential oil (EO) with great antifungal activity but its limited use in the food industry is related to its low solubility and high susceptibility to environmental conditions. Therefore, this study aimed to microencapsulate citral using Arabic gum and sodium alginate as wall materials and evaluate the antifungal activity of the obtained microcapsules in banana fruit. Microcapsules with smooth surfaces and sizes ranging from 1 to 17 μm were obtained after the spray-drying process, retaining 42.48% of the volatile fraction of citral and 28.56% of the total weight of the EO added into the emulsion. The microencapsulation process increased the thermal stability of the EO from 37 to 148 °C. Besides, the microcapsules protected EO from ultraviolet light, and the obtained high glass transition temperature could contribute to the maintenance of microcapsules properties during the storage. The microcapsules of citral showed antifungal properties against Fusarium pseudocircinatum, reducing nearly 56% of the disease caused by this fungus in bananas. These results were related to the properties of the wall materials and method used to obtain the microcapsules. In conclusion, the microcapsules of citral obtained by spray-drying can be an alternative to control the post-harvest decay in tropical fruits such as bananas. Graphical abstract: [Figure not available: see fulltext.]