Tomato shelf-life extension at room temperature by hyperbaric pressure treatment

Abstract

The effect of hyperbaric treatments on major hydrophilic and lipophilic antioxidants and antioxidant activity in tomato fruit, using ORAC and TEAC assays, was studied. Early breaker stage greenhouse grown tomatoes were subjected to different pressure and temperature conditions, including 0.1 (ambient atmospheric pressure, control), 0.3, 0.5, 0.7 and 0.9MPa at 20°C, and 0.1MPa at 13°C (cold treatment) for 4 days, followed by ripening at 20°C for 5 and 10 days. Hyperbaric treatment significantly affected lycopene content by inhibiting, then enhancing its accumulation during treatment and ripening, respectively. In general, ascorbic acid and total phenolic contents increased as time progressed but generally were not affected by hyperbaric pressure treatment. All antioxidants were found in lower concentrations in tomatoes treated at 13°C. The trend in antioxidant activity obtained from both ORAC and TEAC assays was generally similar. No significant effect of hyperbaric treatment on lipophilic antioxidant (LAA) and hydrophilic antioxidant (HAA) was observed compared with control tomatoes at 13 and 20°C. However, the ORAC assay showed that hyperbaric treated tomatoes had significantly higher HAA than 13°C treated tomatoes. Overall, hyperbaric treatment at 20°C has potential to extend tomato shelf-life during short treatment durations without adverse impact on quality during ripening.