Making Post-harvest More Efficient: Prototyping an Air Treatment Plant for PGI ‘Cipolla Rossa di Tropea Calabria’ Spring Onions

The Red Onion of Tropea Calabria IGP is one of the most prestigious Italian products. Regarding the post-harvest processing of this product, the type of mechanical equipment used plays an important role. Generally, spring onions are processed in mechanical installations that use large quantities of water to wash, cut, and partially peel them simultaneously. These machines typically feature shearing knives that cut both the roots and the leaves, two pairs of rotating brushing rollers that peel the onions, and special sprayers that wash them at the same time. At the end of this process, the water can cause problems for the onions as it may stagnate in the cuts, spoiling them and reducing their shelf life. A solution to this problem is a newly developed system that uses compressed air instead of water to wash the onions. This system will be investigated in this research.