Department of Food Science and Nutrition, Zhejiang University, Hangzhou 310058, PR China.
J Sci Food Agric. 2012 Dec;92(15):3016-22. doi: 10.1002/jsfa.5717. Epub 2012 May 2.
Tomato fruit is usually stored at low temperatures for delayed ripening and extended shelf life. However, tomato fruit is susceptible to chilling injury when exposed to low temperatures. In this study, the potential effects of preconditioning with UV-C or UV-B irradiation on chilling injury of postharvest tomato fruit were investigated.
Mature-green tomato fruit were exposed to 4 kJ m(-2) UV-C or 20 kJ m(-2) UV-B irradiation and stored for 20 days at 2 °C and subsequently 10 days at 20 °C. UV irradiation was effective in reducing chilling injury index and delaying ethylene peak. Furthermore, UV irradiation preserved storage quality as manifested by reduced weight loss, better retention of firmness, and higher contents of total soluble solids, soluble protein and soluble sugar during subsequent storage at 20 °C. UV-C irradiation significantly delayed the development of the red colour after 10 days of storage at 20 °C. On the other hand, UV irradiation decreased total phenolics content and antioxidant capacity, suggesting possibly reduced stress response to low temperature resulted from enhanced physiological adaptation by UV preconditioning.
Our results suggest that preconditioning with UV-C or UV-B irradiation in appropriate doses had a positive effect on alleviating chilling injury in postharvest tomato fruit.
番茄果实通常在低温下储存以延缓成熟和延长货架期。然而，番茄果实在低温下易受冷害。本研究探讨了 UV-C 或 UV-B 辐照预处理对采后番茄果实冷害的潜在影响。
成熟绿番茄果实暴露于 4 kJ m(-2) UV-C 或 20 kJ m(-2) UV-B 辐射下，并在 2°C 下储存 20 天，随后在 20°C 下储存 10 天。UV 辐射有效降低了冷害指数并延迟了乙烯峰的出现。此外，UV 辐射通过减少失重、更好地保持硬度以及在随后 20°C 下储存时提高总可溶性固体、可溶性蛋白质和可溶性糖的含量来保持贮藏品质。UV-C 辐射显著延迟了在 20°C 下储存 10 天后的红色颜色的发展。另一方面，UV 辐射降低了总酚含量和抗氧化能力，这表明可能由于增强的生理适应导致对低温的应激反应降低。
我们的结果表明，适当剂量的 UV-C 或 UV-B 辐照预处理对缓解采后番茄果实的冷害有积极影响。
