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

• Non-conventional MAP reduced respiratory rate and C2H4 emission of fresh-cut watercress leaves.
• Non-conventional MAP lowered mesophilic microbial growth throughout 3 days at 5 °C.
• An increase in antioxidant activity was found with regard to air conditions.
• Non-conventional MAP maintained over all quality of fresh-cut watercress leaves.

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.