Effect of non-conventional modified atmosphere packaging on fresh cut watercress (Nasturtium officinale R. Br.) quality

In recent years, the minimally processed food industry has increased due to a consumer trend toward healthier eating. Among these products, watercress represents an interesting alternative due to its high content of functional compounds. The aim of this study was to investigate the effect of non-conventional modified atmosphere packaging (nitrogen (89.7% N₂, 10.3% O₂), argon (89.9% Ar, 10.1% O₂), helium (90.1% He, 9.9% O₂), nitric dioxide (89.3% N₂O, 10.7% O₂) and air (0.03% CO₂, 21% O₂)) on fresh-cut watercress leaves preserved for 13 days at 5 °C. The respiratory rate was reduced by the non-conventional atmosphere up to 3 days of storage, and no significant effects were observed on C₂H₄ production. In addition, mesophilic microbial growth was reduced up to 3 days of storage, and no effect was observed on psychrotrophic and Enterobactericeae counts. He and N₂O atmospheres increased the antioxidant activity of watercress at the end of the storage period. Nevertheless, there was no clear effect of non-conventional gases on the color parameters, polyphenol contents and sensory parameters of fresh-cut watercress.