Maintaining Postharvest Quality of Fruits by Using Essential Oils

Abstract

Date fruits loss their quality during storage after being harvested and ripen because of the microbial decay, which is caused by fungi. Fungicides were used to get rid of fungi, but some fungal pathogens were reported to develop resistance to synthetic fungicides. Natural compounds such as essential oils get a lot of attention to be used as an alternative for chemical compounds (fungicides), due to their biodegradability. They are found to play a good role in maintaining fresh fruits quality as date and inhibit the development of fungi after being harvested in a healthy and safe way. The objective of this study was made to test the effect of spraying the essential oils Peppermint and Lemongrass on date. The date fruits were sprayed with Peppermint and Lemongrass essential oils of concentration 1 and 2% for each. The sprayed fruits were stored for 40 days at room temperature from 20 - 23ºC. In this experiment some chemical and physical characteristics were identified during storage such as percentage of weight loss and percentage of decayed fruits, moreover the total soluble pectin, total phenols and antioxidant activity. Antifungal activities of the two essential oils against Aspergillus niger and Penicillium were measured. Chemical compositions of the essential oils were identified by GC-MS. The results indicated that the physical and the chemical properties of the fruits were enhanced by sprayed with all essential oil treatments. A considerable delay in the properties of fruits comparing with the untreated fruits (control). Concerning to antifungal activities of the two essential oils against Aspergillus niger and Penicillium, Lemongrass essential oil of 2% had the highest effect.