Effect of 1-MCP treatment on the apple (Malus domestica L. Borkh.) allergen Mal d 1 during long-term storage

The consumption of apple fruits can induce allergic reactions. The major allergen responsible for these allergic reactions in Central Europe and North America is the apple allergen Mal d 1, the synthesis of which depends on the apple cultivar and increases during storage time. Several studies have investigated the impact of the cultivar and storage conditions on the Mal d 1 content in apple fruits. However, there are few data available on the impact of 1-methylcyclopropene (1-MCP) on Mal d 1 synthesis during long-term storage. In this study, the Mal d 1 content of seven different apple cultivars was analyzed. Half of the fruits were treated with 1-MCP (Smart Fresh™, Agro Fresh Inc. Spring House, PA, USA). After treatment, the fruits were stored for 12, 20, 28 and 36 weeks in a cold chamber at 2 °C as well as for 12, 20, 28, 36 and 44 weeks under controlled atmosphere (CA-storage, 1.5% CO2, 1.5% O2, 2 °C). The Mal d 1 contents of all apple cultivars increased during storage. With the exception of 'Boskoop', Mal d 1 contents of all of the fruits treated with 1-MCP were significantly lower than those of the fruits in the untreated control group.

► The impact of 1-methylcyclopropene (1-MCP) on Mal d 1 synthesis was investigated. ► Seven popular apple cultivars with low, moderate and high Mal d 1 contents were chosen. ► Mal d 1 contents were analyzed during longtime storage for 44 weeks. ► Fruits treated with 1-MCP had significant lower Mal d 1 contents than the untreated. ► 1-MCP possibly can make apple consumption more tolerable for allergic people.