1-MCP处理和贮藏温度对黑宝石李果肉褐变的影响

为了探明李果实褐变机理并抑制褐变,研究了1-MCP处理和贮藏温度对黑宝石李果肉冷害褐变、机械伤褐变、多酚氧化酶(PPO)活性、总酚含量和乙烯释放的影响.结果表明,黑宝石李果实在(0±0.5)℃和(3±0.5)℃条件下分别贮藏75d和60d会发生果心的冷害褐变,在(7±0.5)℃下不会发生冷害褐变,但贮藏期短;机械伤诱导李果实在冷藏2d后发生近果皮处果肉的褐变症状.5μL/L 1-MCP处理李果实12h后,在(0±0.5)℃贮藏时可有效抑制冷害褐变和机械伤褐变,但在(3±0.5)℃和(7±0.5)℃时促进果肉褐变.PPO活性和总酚含量的变化与李果实褐变相关,但不是褐变的诱发原因.

Effect of 1-MCP Treatment and Storage Temperature on Pulp Browning of Friar Plum(Prunus salicina Lindell. cv. Friar)

Pulp browning seriously limits the dietary property and commercial value of plumfruit.In order to elucidate the browning mechanism of plum and to inhibit pulpbrowning, the effect of 1-MCP treatment and different storage temperature on chilling injury browning, mechanical injury browning, PPO activity, total phenols concentration and ethylene production of Friar plum was studied.The results indicated that, chilling injury browning of Friar plum developed after 75 or 60 days of storage at (0±0.5)℃ or (3±0.5)℃, but never developed when fruitswere stored at (7±0.5)℃, at which temperature, the storage period was short.Moreover, mechanical injury browning developed in pulp near peel after two days of storage at low temperature.Browning symptoms were efficiently reduced by 5μL/L1-MCP treatment for 12h when fruits were stored at (0±0.5)℃.However, when the storage temperature was (3±0.5)℃ or (7±0.5)℃, fruits treated with 1-MCP showed more serious browning symptoms than untreated fruits.In any case, both two kinds of browning are related to PPO activity and total phenols concentration.