超高压处理对哈密瓜汁品质的影响

Effect of ultra-high pressure treatment on the quality of hami melon (cucumis melo l.) juice

选择新鲜哈密瓜为试验材料,采用100～500MPa超高压协同25～55℃,分别对哈密瓜汁处理5～20min,同时以常压下不同温度处理作对照,对各处理前后的哈密瓜汁的基本理化指标(pH值、可溶性固形物、浊度)、还原型Vc、色差值(L、a、b)及瓜汁中的菌落总数进行检测。结果显示:哈密瓜汁在处理前后其pH值、Brix、浊度无明显变化,还原型Vc含量随压力、温度的上升及处理时间的延长均有所下降,其中55℃处理时下降最为明显,同时瓜汁的色泽均有所改善,L值升高。超高压处理对哈密瓜汁有很好的杀菌效果,400MPa、45℃已无菌落检出。

In this paper,the fresh hami melon was selected as the trial material. Hami melon juice was treated with the ultra-high pressure at 100～500 MPa for 5～20 min synergy temperature of 25～55 ℃,and the controlled melon juice sample was treated with atmospheric pressure and temperature. The basic physicochemical qualities （pH,soluble solids,turbidity）,reduced Vc,color values（L,a,b） and the total number of colonies in melon juice were tested. It was shown that the pH value,brix and turbidity of hami melon juice has no significant changes before and after treatment, however, the Vc content has declined, especially obviously at 55 ℃. The color of treated hami melon juice has been improved combined with L value increased. When pressure was 400 MPa, and temperature was 45℃, no colonies were detected. Ultra-high pressure, a non-thermal preservation technique to pasteurize melon juice, proved to efficiently induce microbial as well as preserved some quality attributes.