Green, healthy apples even after long storage
A third of South Tyrol's apple harvest is at risk of storage damage. Dynamic controlled atmosphere (DCA) storage could significantly improve the fruit's shelf life and quality.
A third of the apple harvest in South Tyrol is at risk of storage damage, so effective post-harvest management is essential to maintain the fruit's quality and extend its shelf life. In his session ‘Optimising post-harvest quality through dynamic storage in a controlled atmosphere’ on the Farming Forward Stage at FRUIT LOGISTICA 2026, Angelo Zanella from the South Tyrolean Research Centre Laimburg discussed how this can be achieved.
“Controlling the oxygen level is our main task. This is because a low oxygen content leads to a longer and better storage life," the researcher explained. However, depending on the variety, there is a minimum level that must not be fallen below. While traditional controlled atmosphere storage relies on static gas compositions, Zanella advocates dynamic approaches that are tailored to the physiology of the fruit in question.
Researcher Angelo Zanella speaks on the Farming Forward Stage about optimal post-harvest management using new DCA methods. Copyright: Messe Berlin
Precise adjustment of oxygen content
So-called Dynamic Controlled Atmosphere (DCA) systems actively regulate storage conditions — particularly oxygen content — to the lowest tolerable threshold, thereby inhibiting aerobic metabolism and delaying ripening. According to Zanella, DCA-CF (DCA method based on chlorophyll fluorescence) has become the most widely used of these. This technique uses real-time biosensors to detect metabolic stress through sudden changes in fluorescence, enabling precise adjustment of the oxygen content.
Advantages include residue-free preservation, reduced enzymatic browning, control of storage-related damage and diseases, and improved preservation of quality characteristics. “However, this only applies during storage, where the oxygen level can be kept low. The effect differs for each variety,” said the researcher. ‘We therefore face challenges when unsold fruit has to be stored for longer periods, as well as during transport to distant target markets and during long sales periods under difficult climatic conditions.’
The combination of DCA-CF with the ripening hormone
The combination of DCA-CF and the synthetic plant hormone 1-MCP, which slows down ripening, has proven effective here. To test this, Zanella and his team simulated seven months of storage in DCA-CF with the addition of 1-MCP, followed by 40 days of transport to India and 21 days on supermarket shelves, where it was kept at 30°C during the day and 10°C in cold storage at night. 'The quality was similar to that at harvest,' they concluded.
However, the expert admits that there is a loss of flavour. Each variety also reacts differently. ‘My suggestion is to continue researching and testing combinations of different techniques on different products to find the optimal storage method,’ Zanella recommended.