The apple is a textbook example of a 'breathing' fruit that continues to ripen after being harvested. The starches gradually turn into sugars. The sourness drops. The color turns yellow. And the apple turns soft. Only then does the characteristic flavor of the apple truly come out. In the next stage, when the apple is kept in storage, the nutrients are used up. The apple further softens and becomes juicier, but then decay sets in. The product quality declines and the fruit spoils. Most apple varieties can be kept in cold storage, and the use of 1-MCP can further extend their shelf life.
The use of 1-MCP can significantly slow down the apple's metabolism and ethylene production. The apple effectively stops 'breathing' and the peak of ethylene production is delayed. 1-MCP is therefore efficient in keeping the apple firm, the sugar content just right, and the color as fresh as possible. In addition, 1-MCP can reduce and even eliminate frost damage in cold storage as well as the damage from plant diseases.
In general, the sooner the apples are fumigated with 1-MCP after being harvested, the more efficiently the shelf life can be extended. However, there are two points of notice: first, pre-cooling. For example, if the apples are placed in a refrigerated room without pre-cooling, then the 20℃ temperature difference can harm the physiology of the apples. Residual heat leads to poor product quality. The apples should first be placed in a well-ventilated, dry place, preferably in the shade, for the duration of the day and then cooled in the evening.
Second, cold room management. The smell in cold rooms is eliminated with potassium permanganate or sulfur, which will disinfect the cold room. The room should then be kept at 0°C for two days before the pre-cooled apples are placed in the room. The apples should be stacked in such a way that air can move between them. Once all the apples are placed in the cold room, the temperature can be adjusted. The apples remain in the room for 10 days before they are treated with 1-MCP. The apples that have been treated with 1-MCP can remain in storage for about 6-12 months. The apples remain firm and the sugar content is higher than in apples that are kept in air-conditioned rooms. The apples should be treated with 1-MCP before they are left to breathe, or the effect is not as strong. After treatment, the apples should be kept in storage at the same temperature as apples in air-conditioned rooms. For most apple varieties the preferred temperature is around 0°C. The concentration of 1-MCP is not the same for different apple varieties, but for most it is around 1μL/L. The effect of 1-MCP on different apple varieties is as follows:
1. Gala apples
1-MCP helps to inhibit the metabolism and ethylene production of Gala apples whether in large-scale cold storage or in smaller experimental storage units. The effect of different concentrations of 1-MCP is not that significant. Data shows that untreated apples have a hardness of 6.3 kg per square cm, while apples treated with 1-MCP have a hardness of 8 kg per square cm, even after 120 days in storage. 1-MCP clearly reduces the decline in hardness for Gala apples in storage. That is how 1-MCP extends the shelf life of Gala apples and maintains product quality.
2. Fuji apples
The Fuji apples are the most successful example of 1-MCP treatment in China. Furthermore, this brings the cost price of cold storage down in comparison with the cost price of storage in air-conditioned warehouses, which is why 1-MCP treatment is widely applied by Fuji apple traders. Research has shown that 1-MCP can significantly inhibit the metabolism and ethylene production in Fuji apples, both in cold storage and at room temperature. This clearly shows that 1-MCP treatment can guarantee the product quality of Fuji apples in storage.
Chesen BioChem is not yet a registered supplier of 1-MCP products in overseas markets, but the company is working hard to find licensed retailers with an interest in cooperation.
For more information:
Chesen BioChem Co., Ltd.
Tel.: +86 181 3360 9421