本研究旨在探讨不同物理方法作用于水蜜桃的保鲜效果及其机理,以期获得一种安全高效的新型复合物理保鲜方法.研究以江苏省张家港市凤凰镇的凤凰水蜜桃白花品种(Prunus persica.cv ‘Baihua’)为试验材料,分析了在室温条件(30±5)℃下利用竹炭包装、UV-C照射、超声波清洗和预冷(3℃)的单一及复合处理对凤凰水蜜桃的保鲜效果.结果表明:各物理方法均具有一定的保鲜效果,预冷可显著(P<0.05)推迟呼吸高峰;UV-C在降低呼吸速率和维持细胞膜结构方面优于其他处理;竹炭处理可有效维持果实硬度和抑制MDA的增长;复合处理组效果最好,贮藏第14d时,复合处理的失重率、硬度和可溶性固形物含量的下降速率分别低于对照组2.45个百分点,92.78%,26个百分点,呼吸高峰由4d推迟至10d,MDA增长和PPO酶活性增强的速率分别低于对照组82.60%和11.04%,而且该复合处理方法操作简便、安全高效.因此,“竹炭包装+UV-C+超声波清洗+预冷”的新型复合物理保鲜方法能在保证果实品质的前提下有效延长水蜜桃的保鲜期和货架期.
In order to explore the effects and mechanism of physical preservation methods and find out a new combined physical effective way to preserve peaches which fits the food safety policy, the Fenghuang honey peaches picked from Zhangjiagang, Nanjing Province, were selected as the experiment materials. At normal temperature (30±5) ℃, the effect was compared and analyzed using charcoal packaging, UV-C irradiation, ultrasonic cleaning, pre-cooling either separately or all combined. The results showed that different physical method had played a role in the preservation. The pre-cooling treatment was significantly (P〈0.05) better in delaying respiratory peak. The UV-C irradiation treatment was superior to other treatments in reducing respiratory rate and maintaining cell membrane structure while the charcoal treatment could effectively maintain fruit firmness and suppress the growth of MDA. However, the combined treatment was the best. On the 14th day, the value of weight loss of combined treatment was 2.45 percentage point lower than the controlled group. The value of firmness of combined treatment was 92.78% and the value of soluble solids content was 26 percentage point lower than the controlled group. The fourth day was postponed to tenth day to reach respiratory peak. The MDA growth rate of combined treatment was 82.60% and PPO growth rate was 11.04% lower than the controlled group. What's more, the combined method is simple, safe and efficient. Thus, the new combined physical treatment of "charcoal packaging + UV-C irradiation + ultrasonic cleaning +pre-cooling" is an effective way to extend the shelf life of peaches which fits the food safety policy and maintains the quality.