O_2联合CO_2气调对西兰花活性氧代谢及保鲜效果的影响

Effects of O_2 Combined with CO_2 Controlled Atmospheres on Reactive Oxygen Species Metabolism and Quality Preservation of Broccoli(Brassica oleracea L.)

设置100%O2、80%O2+20%CO2、60%O2+40%CO2、40%O2+60%CO2、20%O2+80%CO2气体组合,以自然大气为对照(CK),对15℃贮藏过程中西兰花的活性氧代谢及品质指标进行测定。结果表明:100%O2处理促进西兰花呼吸和乙烯释放,加速过氧化氢(H2O2)和超氧阴离子自由基(O-2·)产生以及丙二醛(MDA)积累,促进叶绿素和VC含量的降低,缩短了保鲜期;而20%O2+80%CO2处理虽能很好的维持叶绿素含量,但易导致西兰花VC的迅速丧失并产生异味现象;40%O2+60%CO2处理显著降低呼吸速率和乙烯释放量,减少H2O2和O-2·产生,抑制MDA的积累,并较好的维持了叶绿素和VC含量,表现出很好的保鲜效果。

This study was done to investigate the effects of controlled atmospheres with different levels of O2and CO2： 100% 02, 80% 02＋ 20% CO2, 60% O2 ＋ 40% CO2, 40% O2＋ 60% CO2 and 20% 02＋ 80% CO2 on reactive oxygen metabolism and quality preservation of broccoli （Brassica oleracea L） during storage at 15 ℃ in comparison to natural air as a control. Results showed that the 100% O2 treatment increased the respiration rate and ethylene production, promoted the production of hydrogen peroxide （H202） and superoxide anion radical （O2^- ＊ ） and the accumulation of malondialdehyde （MDA） content, accelerated the losses of chlorophyll and vitamin C （VC） content, and shortened the shelf life of broccoli. Although chlorophyll content was well maintained, the 20% 02 ＋ 80% CO2 treatment promoted the loss of VC content and led to off-flavor whereas the 40% O2 ＋ 60% CO2 treatment exhibited excellent storage characteristics, which dramatically decreased the respiration rate and ethylene production, reduced the production of H202 and O2- · , delayed the accumulation of MDA, and maintained higher contents of VC and chlorophyU. These observations demonstrate that treatment with a combination of O2 and CO2 in proper concentration ratio could have good effects on the maintenance of broccoli quality during storage.