Comparison of antifungal activity of essential oils of clove, lemongrass and thyme for natural preservation of dried apricots

Abstract

Currently, the majority of fresh apricots destined for the production of dried apricots undergo sulphur oxide fumigation before drying to protect the fruit against fungal spoilage. To eliminate the use of sulphite, packaging assisted with essential oil is a promising strategy to increase shelf-life of dried apricots since it does not impact its flavor characteristics. In this study, three essential oils were selected: clove, lemongrass and thyme. They were screened for antifungal activity against Eurotium spp. with different methods: micro- and macro-dilution and agar-diffusion. Growth/no-growth data were used to develop models for all three methods. Clove exerted the strongest antifungal activity with an inhibitory concentration of 0.075%, 0.035% and 0.05% through respectively micro-dilution, macro-dilution and agar diffusion. For thyme the following values were obtained: 0.775%, 0.070% and 0.100%. This means that the antifungal activity of thyme is 10 times lower in micro-dilution and 2 times lower in macro-dilution and agar diffusion compared to clove. Through micro-dilution, lemongrass was found to have the second highest antifungal activity (0.25%). When used in the volatile atmosphere of dried apricots and in macro-dilution, the antifungal activity of lemongrass was the lowest, with respective values of > 0.200% and 0.105% for G/NG prediction.

Recent advances in nutritional composition, phytochemistry, bioactive, and potential applications of Syzygium aromaticum L. (Myrtaceae)

“…Syzygium aromaticum showed beneficial advantages in antibacterial and antifungal activity, aromaticity and safety, especially against a wide range of food-borne microorganisms, making it a potential and valuable preservative in the food industry. The antifungal activity of clove is superior to that of lemongrass and thyme essential oils to prevent the natural preservation growth of fungi on dried apricots (122). Ju et al (123) confirmed by accelerated storage tests that the CEO can extend the shelf life of food bakery products by 2-4 days under normal packaging.…”