Suitability of gamma irradiation for preserving fresh-cut watercress quality during cold storage

• Packaged samples of fresh-cut watercress were irradiated at 1, 2 and 5 kGy.
• Quality parameters were analysed after harvest and 7 day cold storage.
• Sucrose, malic and fumaric acids, MUFA, PUFA and tocopherols increased during storage.
• The overall quality of fresh-cut watercress was better preserved with the 2 kGy dose.
• The 5 kGy dose better preserved the antioxidant activity and total flavonoids.

The suitability of gamma irradiation (1, 2 and 5 kGy) for preserving quality parameters of fresh-cut watercress (Nasturtium officinale R. Br.) during storage at 4 ± 1 °C for 7 d was investigated. The storage time decreased the protein content and the main carbohydrates, and increased the levels of malic and fumaric acids, sucrose and mono- and polyunsaturated fatty acids (MUFA and PUFA). The different irradiation doses did not caused any significant colour change. In general, the 2 kGy dose favoured PUFA and was the most suitable to preserve the overall postharvest quality of fresh-cut watercress during cold storage. In turn, the 5 kGy dose better preserved the antioxidant activity and total flavonoids and favoured MUFA, tocopherols and total phenolics, thus originating a final product with enhanced functional properties. Therefore, the suitability of gamma irradiation for preserving fresh-cut watercress quality during cold storage was demonstrated.