CO_2对模拟运输条件下西兰花品质和贮藏特性的影响

Effect of CO_2 on Quality and Storage Characteristic of Broccoli under Simulated Transport Conditions

目的为了研究添加CO_2生成剂对西兰花运输过程中花球品质和代谢特性的影响,以及筛选西兰花运输过程中适宜的CO_2浓度。方法以西兰花为实验材料,研究不同浓度CO_2(二氧化碳生成剂)对西兰花花球采后模拟运输条件下生理特性和品质的影响。结果保持较低体积分数(3%和6%)的CO_2能较好地抑制西兰花采后运输条件下的呼吸强度,延缓乙烯释放量增加的时间和速率,抑制花球叶绿素的降解,保持花球的颜色,同时降低了西兰花在运输期间的腐烂指数。通过进一步的研究结果表明,经体积分数为3%CO_2处理后延缓了货架期间花球中丙二醛(MDA)含量的升高速率,添加一定浓度的CO_2(3%)后通过诱导过氧化氢酶(catalase,CAT)和过氧化物酶(peroxidase,POD)的活性,提高了西兰花组织内部活性氧的清除能力,从而保持了花球的品质。添加较高浓度(9%和12%)的CO_2在运输前期(前3 d)具有较好的保鲜效果,之后反而会促进花球的代谢速率(呼吸强度和乙烯生成量),从而加速了花球的黄化及腐烂,表现出被伤害的症状。结论运输前在包装内加入可产生体积分数3%CO_2的生成剂能较好地降低西兰花常温运输期间的代谢水平,保持花球品质,从而延长了运输时间。

The work aims to study the effect of addition of CO2 generation agent on the ball quality and metabolic properties in the process of transporting broccoli and screen the proper concentration of CO2 in the package during such process. Broccoli was used as experimental material to study the effects of CO2(carbon dioxide generation agent) at different concentrations on physiological characteristics and quality of broccoli ball under simulated transportation conditions after harvest. Keeping a low volume fraction(3% and 6%) of CO2 could better inhibit the respiratory intensity of broccoli during post-harvest transportation, delay the time and rate of increase of ethylene release, inhibit the degradation of chlorophyll in the flower ball, maintain the color of the flower ball, and reduce the decay index of broccoli during transportation. According to further research results, the treatment with CO2(volume fraction: 3%) also delayed the increase rate of malondialdehyde(MDA) content in the flower ball during shelf life. A certain concentration of CO2(3%) may improve the scavenging ability of active oxygen in broccoli tissue by inducing the catalase(CAT) and peroxidase(POD) activities, thus maintaining the quality of the flower ball. The higher concentration of CO2(9% and 12%) hada better fresh-keeping effect in the first 3 days of transportation, but later promoted the metabolic rate(respiratory intensity and ethylene production) of the flower ball, accelerated the yellowing and decay of the flower ball and showed the signs of injury. The addition of CO2(volume fraction: 3%) generation agent to the package before transportation can better reduce the metabolic level of broccoli during normal temperature transportation and maintain the quality of flower balls, thus prolonging the transportation time.