Free and encapsulated orange essential oil into a β‐cyclodextrin inclusion complex and zein to delay fungal spoilage in cakes

Abstract

This study investigated the in vitro antifungal activity of orange essential oil (OEO) against Aspergillus spp. and evaluated the activity of free and encapsulated OEO to delay fungal spoilage in cakes. The OEO was encapsulated into a zein and β‐cyclodextrin inclusion complex at three concentrations (2.5%, 5.0%, and 7.5% w/v) by anti‐solvent precipitation method and dried by electrospraying. The OEO inhibited the growth of all Aspergillus species tested. The minimal inhibitory concentration values of OEO were between 45.24 and 90.47 mg/ml and the minimal fungicidal concentration (MFC) values ranged from 45.24 to >180.95 mg/ml. Aspergillus terreus (MV 3529) was the most sensitive to OEO, followed by Aspergillus niger (MV 3531 M 1354), and Aspergillus fumigatus was the most resistant to OEO (MFC of ≥180.95 mg/ml). The OEO delayed the microbiological spoilage of cakes from 30 to 150 days, suggesting its use as a natural antifungal in bakery products. PRACTICAL APPLICATIONS: Fungal contamination in bakery products generates economic losses to the baking industry and consumers’ dissatisfaction. The addition of chemical preservatives to the process can retard fungal deterioration and prevent this problem. However, consumers have been looking for friendlier and ecologically sustainable preservation techniques as alternatives to chemical additives. These alternatives include the utilization of essential oils (EOs), such as orange essential oil (OEO). Despite several studies stating the antifungal effect of EOs, very few reports the actual application in bakery products. These can be added to cake formulations in the free form or encapsulated into a zein and β‐cyclodextrin inclusion complex. In this study, the OEO delayed the microbiological spoilage of cakes from 30 to 150 days, showing that the OEO could be used as an alternative to chemical preservatives, aiming to extend the shelf life of bakery products.