Marino B. Arnao

Melatonin has been shown to be effective as a post-harvest agent in fruits and vegetables. Melatonin has been used in the preservation of Brassicaceae such as broccoli, but not in broccolini. Here, fresh-cut broccolini (baby broccoli or BIMI®) were treated with different concentrations of melatonin (50 and 100 µM) for 15 or 30 min and cold stored for 28 days. Melatonin-treated broccolini had a longer shelf life than control samples, as seen by fresh weight (weight loss rate), hue angle (expresses color quality), and chlorophyll and carotenoid concentrations. Treatments with 50 µM melatonin for 15 min appear to be the most effective, reducing water loss by around 28% compared to the control and increasing the shelf life of fresh-cut broccolini, presenting an optimal conservation time of 7 days, and this could even be extended up to 14 days with acceptable quality. In addition, antioxidant, phenolic, and flavonoid contents were improved in melatonin-treated broccolini plants. Lipid peroxidation damage by cold storage was decreased in melatonin-treated broccolini, with a relevant decrease in malondialdehyde contents, especially 50 µM, on all days of storage. This study demonstrates for the first time the effectiveness of melatonin treatments in extending the shelf life of broccolini during cold storage. The possible commercial use of these treatments will be subject to the processes in the product management and marketing chain. However, more specific research about changes in organoleptic properties is necessary.