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.

摘要：本研究旨在评价迷迭香、肉桂、香茅及丁香精油对扩展青霉（*Penicillium expansum*）体外生长、蓝霉病病斑直径的影响，以及不同冷藏时长下‘富士’苹果的理化品质属性。本研究测定了各精油的成分，并在0、100、1000 μL·L⁻¹的精油浓度下，评价了其对真菌孢子体外生长抑制、孢子数量及活力的影响。采后阶段，分别对经0、50、100、500 μL·L⁻¹精油处理并冷藏30天的果实，以及经0、100、500 μL·L⁻¹精油处理并冷藏2天的果实开展品质评价。结果表明，迷迭香精油中的桉叶素、肉桂与丁香精油中的丁香酚、香茅精油中的香茅醛，可在孢子萌发诱导24小时后，抑制扩展青霉的生长、降低孢子数量与活力，并减小苹果蓝霉病病斑直径；但香茅精油在500 μL·L⁻¹浓度下，经30天冷藏后无上述抑菌效果。经不同浓度精油处理的苹果，在冷藏5个月后置于室温环境7天，其理化品质属性无显著变化。