低温和差压式预冷对不同品种桃果实预冷性能的影响

Effects of Low Temperature and Forced-air Precooling on Precooling Performance of Different Varieties of Peach Fruits

为探讨不同品种桃果实的预冷性能及低温预冷和差压式预冷的差异性,分别以山东6个主栽品种的桃果实为试材,研究预冷期间不同品种桃果心温度的变化。结果表明：不同品种桃的预冷特性有一定的差异。低温预冷前期（预冷10 h以内）,各品种桃果实的果心温度下降速率依次为：仓方早生〉美脆〉红珊瑚〉红不软、朝晖和早凤王,随着预冷时间的延长,差异性降低;与低温预冷相比,差压式预冷可显著缩短果实预冷所需的时间,以上各品种的果心温度由32℃下降到11℃所需的时间分别是低温预冷的1/3-4/5。由于不同品种桃果实的预冷时间有一定的差异,应根据品种的具体特点制定相应的预冷工艺。

In order to explore precooling performance in different varieties of peach fruits and differences between precooling and forced-air precooling,taking six main varieties of peach fruits in Shandong as tested materials respectively,the changes of core temperatures of different varieties of peach fruits were studied.The results showed that,there were some differences in precooling performance of different varieties of peach fruits.During earlier stage of low temperature precooling（less than 10 h）,the core temperature decreasing rates of all varieties of peach fruits were as follows：Cangfangzaosheng〉Meicui〉 Hongshanhu〉Hongburuan,Zhaohui and Zaofengwang,and with the prolongation of the precooling time,the differences reduced.Compared with low temperature precooling,forced-air precooling could significantly shorten the fruit precooling time.The time of core temperature of above all varieties decreased from 32 ℃to 11 ℃ was 1/3 to 4/5 of low temperature precooling.Because there were certain differences in the precooling time of different varieties of peach fruit,so we should make the precooling process according to the specific characteristics of varieties.