紫外及微波处理对鲜切石榴籽粒保鲜品质的影响

以‘泰山三白甜’石榴成熟果实为试材，分别用频率为2 450 MHz的微波处理10 s和功率为30 W紫外灯照射15 min后装入保鲜袋后于（4±0.5） ℃冷藏保鲜15 d，比较2 种处理方式对鲜切石榴籽粒品质及抗氧化活性的影响。结果表明：紫外照射能降低石榴籽粒冷藏过程中的质量损失率、腐烂率及相对电导率，延缓总可滴定酸含量的骤变期，使籽粒中各有机酸及VC含量维持在较稳定的水平，而微波处理增大了石榴籽粒冷藏中后期的质量损失率、腐烂率、相对电导率及乳酸含量；2 种处理对鲜切石榴籽粒冷藏过程中柠檬酸含量的变化均无显著影响，对冷藏初期（3～6 d）1,1-二苯基-2-三硝基苯肼自由基清除率的保持有一定作用，抗氧化活性均较对照高，但对冷藏后期抗氧化活性的保持效果不显著。‘泰山三白甜’石榴鲜切籽粒（4±0.5） ℃最佳保鲜期为6 d，紫外照射处理保鲜效果优于对照和微波处理。

Effects of UV and Microwave Treatments on the Preservation Quality of Fresh-Cut Pomegranates

Ultraviolet (UV) light and microwave (MW) treatments were separately applied after the peeled pomegranate
seeds (‘Taishansanbaitian’ cultivar) were washed with flowing water. Weight loss, decay incidence, titratable acidity,
total soluble solids content, the contents of major organic acids, VC and lactic acid, relative electrolytic leakage and
1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity of the pomegranate seeds were determined every three
days during subsequent storage at (4 ± 0.5) ℃ for up to 15 days. The results showed that UV radiation reduced the weight
loss, decay incidence and relative electrolytic leakage of fresh-cut pomegranate seeds during cold storage, suppressed the
increase in total titratable acid content and maintained the main organic acids and VC contents at a relatively stable level,
while microwave treatment caused in an increase in weight loss, decay incidence, lactic acid content and relative electrical
conductivity during the middle–late stages of storage compared with the control. DPPH free radical scavenging capacity
of both MW- and UV- treated seeds remained higher during the early stages of storage (3–6 days) but decreased during the
late stage. Fresh-cut seeds of ‘Taishansanbaitian’ pomegranate retained its freshness for up to 6 days at (4 ± 0.5) ℃, and the
effect of UV treatment was superior to that of MW treatment and control.