Essential oils for the postharvest control of blue mold and quality of 'Fuji' apples

Abstract

The objective of this work was to evaluate the effect of rosemary, cinnamon, citronella grass, and clove essential oils on the in vitro growth of Penicillium expansum, on the diameter of blue mold lesions, and on the physical and chemical attributes of 'Fuji' apples stored under refrigeration for different periods of time. The compositions of the essential oils were determined, and their effects on the growth inhibition, number, and viability of fungal spores in vitro were evaluated at 0, 100, and 1,000 μL L-1 oil concentrations. At postharvest, evaluations were performed for fruit treated with 0, 50, 100, and 500 μL L-1 essential oil and kept under refrigeration for 30 days, and for fruit treated with 0, 100, and 500 μL L-1 oil and kept under refrigeration for two days. The essential oils - eucalyptol (rosemary), eugenol (cinnamon), citronellal (citronella), and eugenol (clove) - reduce the growth, number, and viability of P. expansum spores 24 hours after the induction to germination, as well as the diameter of blue mold lesions in apples, except for citronella oil at 500 μL L-1 after 30 days of cold storage. There are no changes in the physicochemical attributes of apples, treated with different concentrations of the oils after refrigeration for five months, followed by seven days at room temperature.

Application of Rosemary and Eucalyptus Essential Oils and Their Main Component on the Preservation of Apple and Pear Fruits

“…Great losses of fruits (including apples and pears) have been attributed to the development of postharvest diseases caused by fungal pathogens (i.e., B. cinerea, P. expansum). The use of EOs and natural compounds for the control of fungal growth on fruits has shown encouraging results, however not many studies have included the effects on the quality attributes and/or fruit tissue response to such treatments against fungal pathogens [7,18,22,27,31,32].…”

“…In this essence the investigation of natural products, including essential oils (EOs) from aromatic plants and herbs and other natural compounds has started gaining interest [12][13][14]. Many EOs have been proven to possess antifungal activities (among other properties), including thyme, oregano, cinnamon, clove, eucalyptus, rosemary, garlic EO [14][15][16][17][18]. This activity might be observed either by direct contact via immersion in a solution or by vapor application [12,13,19].…”

“…Previous studies have reported the use of EOs on fresh produce with promising outcomes. Rosemary and eucalyptus EOs have been used during postharvest storage of fruits such as strawberry, tomato, mandarin, apples and grapes, providing decreases in disease development in those products [11,18,[22][23][24]. For instance, the use of rosemary, cinnamon, citronella and clove EOs on 'Fuji' apples suppressed the growth of P. expansum [18].…”

“…When using EOs, one must consider that their efficacy against fungal pathogens (as well as other microorganisms) depends on their composition, concentration, application method and time, pathogen species, as well as the properties of the product being applied to [18]. Moreover, there have been reports that high EO concentrations might adversely affect quality attributes such as the sensory properties (i.e., aroma, taste, color) of the treated fresh produce [12].…”

Black Cumin Essential Oil Vapor Delays Postharvest Chlorophyll Loss in Garden Cress (Lepidium sativum L.)

“…No literature found about the effect of black cumin oil on quality parameters on any leafy vegetables, but Viacava et al (2018) detected that microencapsulated thyme essential oil treatment did not show any significant differences in (-a*/ b*) values on lettuces during the entire storage period. Vieira et al (2018) also found that rosemary, cinnamon, citronella grass, and clove essential oils did not affect on physicochemical attributes of apples. But in the present study, conversely, it was found that black cumin oil vapor caused an increase in the green color of garden cress leaves by the 9 th day, and this effect was changed depending on the concentration and time.…”