Novel Energy-Saving Strategies in Apple Storage: A Review

Storing apples for up to a year is a well-established practice aimed at providing a continuous, locally produced fruit supply to consumers and adapting to market trends for optimized profits. Temperature control is the cornerstone of postharvest conservation, and apples are typically kept at temperatures ranging from 0 to 3 °C. However, the energy-intensive process of the initial cool-down and subsequent temperature maintenance poses significant financial challenges with adverse effects on the carbon footprint. Higher storage temperatures could reduce cooling-related energy usage but also pose the risk of enhanced ripening and quality loss. This work explores different storage technologies aiming to reduce energy consumption, such as 1-methylcyclopropene, ultra-low oxygen, and a dynamically controlled atmosphere with raised temperatures. The integration of advanced monitoring and control systems, coupled with data analytics and energy management, in apple storage is also discussed. These strategies can be implemented without cost-intensive construction measures in standard storage facilities. Furthermore, beneficial side effects of higher storage temperatures in terms of a reduced occurrence of storage disorder symptoms and higher maintenance of quality attributes are also discussed for this special issue on sustainable horticultural production systems and supply chains.