| 查看: 615 | 回复: 5 | |||
| 本帖产生 1 个 翻译EPI ，点击这里进行查看 | |||
[交流]
英译汉 谢谢
|
|||
|
Green vegetables such as broccoli florets and asparagus spears are young, actively growing tissues and consequently have high metabolic and respiratory rates when harvested. These crops are prone to harvest-induced senescence, which is initiated within a few hours after removal from the parent plant (King and O’Donoghue, 1995; Downs and Somerfield, 1997). The senescence program is promoted by ethylene or dehydration and inhibited by cytokinin or sucrose, and is characterized by rapid depletion of sugars and organic acids, proteolysis, lipid peroxidation, increases in free amino acids and ammonia, and alteration of gene expression (King and Morris, 1994; Zhuang et al., 1995; Coupe et al., 2003; McKenzie et al., 2004; Gapper et al., 2005). The changes in gene expression include differentially regulated induction of at least four cysteine proteases (Coupe et al., 2003) and a marked up-regulation of asparagine synthase as a consequence of sucrose depletion (Downs and Somerfield, 1997; Winichayakul et al., 2004). Even in the early stages, these dramatic changes result in loss of fresh flavor and coincident increase in undesirable flavor and aroma. The flavor acceptability of asparagus spears decreased significantly after two days at 1 °C, with an additional decline during the subsequent five days of storage (King et al., 1988). This loss of sensory quality was associated with off flavor development, decreased soluble carbohydrates, and an increase in soluble protein. Benefits of low temperature, high humidity, and controlled atmosphere (CA) or modified atmosphere packaging (MAP) storage The best measures to retard harvest-induced senescence and maintain fresh-like sensory quality are rapid cooling with little delay after harvest and subsequent maintenance of low temperature and high humidity during storage (Toivonen and Forney, 2004; Jones et al., 2006). However, there also has been considerable success in devising suitable CA or MAP conditions for preservation of quality in broccoli florets up to twice as long as in air storage (Jacobsson et al., 2004; Toivonen and Forney, 2004; DeEll et al., 2006). Jacobsson et al. (2004) found that use of low-density polyethylene film, inclusion of an ethylene-absorbing sachet, and a package atmosphere of 5% O , 7% CO for MAP storage gave the best fresh- 2 2 like sensory quality of cooked broccoli. DeEll et al. (2006) showed that use of packets including sorbitol plus potassium permanganate markedly reduced accu- mulation of off odor fermentative volatiles in MAP broccoli during 29 days of storage at 0–1 °C. These good results notwithstanding, there is always the potential for production of malodorous volatile sulfur compounds, most notably methanethiol and dimethyl disulphide, when O falls below 1% or CO exceeds 10% (Forney et 2 2 al., 1991; Hansen et al., 1992; Di Pentima et al., 1995). Quite recently, as a first step toward elucidation of the molecular mechanisms whereby CA delays the rapid onset of harvest-induced senescence in broccoli florets, Eason et al. (2007) used differential display analysis to identify a set of stress response genes induced during the first 24 hours under 10% CO , 5% O CA. |
回复此楼» 猜你喜欢
368化学求调剂
已经有13人回复
-
286求调剂
已经有4人回复
-
0703化学求调剂
已经有12人回复
-
调剂
已经有3人回复
-
材料调剂
已经有13人回复
-
285求调剂
已经有18人回复
-
机械工程313分找工科调剂
已经有3人回复
-
考研调剂-材料类-284
已经有9人回复
-
一志愿厦大生物学332求调剂
已经有3人回复
-
本科211，293分请求调剂
已经有13人回复
» 抢金币啦！回帖就可以得到:
-
天津大学智能人机交互团队招收机械非全硕士带薪培养
+1/486
-
★★爆★★0860生物与医药调剂考生看过来，河北大学化学与材料科学学院
+1/218
-
重庆长江师范学院材料工程接收材料类和机械类考生调剂硕士研究生
+1/175
-
浙江理工大学物理系招收物理学和光电信息调剂生
+2/146
-
【科研项目】破解电池安全密码：揭秘国内首款火灾爆炸与抑制一体化实验舱
+1/92
-
河南工业大学化学化工学院 2026 年硕士调剂火热正在进行中
+1/41
-
济南大学前沿交叉院 招化学学硕（物理可调）或 材料与化工专硕
+1/21
-
上海应用技术大学姚子建课题组招生，点击就送研究生学历
+1/20
-
浙江农林大学 林业与生物技术学院 生物学(生物化学与分子生物学) 第一轮调剂生招生
+1/13
-
三峡大学材化学院化工新材料课题组现招收化学或者化工、材料硕士研究生2名
+5/10
-
武科大冶能学院招收材料、冶金、能源环境、机械等相关专业调剂生
+1/9
-
★上海★上海工程技术大学·环境与资源创新中心（ICER）接收化工材料环境等学科调剂生
+1/8
-
太原科技大学材料科学与工程学院“03高性能轻质合金及新能源材料”学硕与专硕有缺额
+1/5
-
华北理工大学-材料/化学/化工/环境专业
+1/5
-
中国科学院城市环境研究所与福建农林大学联合培养研究生调剂公告（第一批）
+1/5
-
江西水利电力大学市政工程接受调剂
+1/5
-
山西大学招收2026级申请考核制化学材料类博士研究生一名
+1/4
-
一志愿211电子信息347求调剂
+1/4
-
丽水学院材料与能源工程学院 材料与化工、资源与环境专业2026年硕士研究生接受调剂
+1/3
-
【#上海调剂急录#】能接受985联合培养的速来！带你发一区文章！
+1/2
2楼2011-03-04 12:18:20
| 这种衰老过程被乙烯或脱水所促进，为细胞分裂素或蔗糖抑制，并以糖类和有机酸迅速耗竭，蛋白质水解，脂质过氧化，游离氨基酸和氨增加以及基因表达变化为特点(King and Morris,1994; Zhuang et al., 1995; Coupe et al., 2003; McKenzie et al., 2004; Gapper et al.,2005)。基因表达的变化，包括至少四个半胱氨酸蛋白酶差异调节诱导（Coupe et al.，2003）和作为蔗糖消耗的结果的天冬酰胺合成酶向上调节（Downs and Somerfield, 1997; Winichayakul et al., 2004）。即使在早期阶段，这些显著的变化也会导致新鲜口味损失和不良口味和香味同步增加。芦笋口味的可接受度在1 ° C下两天后显著降低，并在其后的五天存储期间进一步下降（King et al., 1988）。这种感官质量损失是与气味丧失的发展、可溶性碳水化合物减少和可溶性蛋白增加相关。 |
3楼2011-03-04 13:51:12
4楼2011-03-04 13:53:49
| 延缓收获诱导的衰老以保持新鲜的感官质量的最好措施是收获后快速冷却，后续维护和储存期间保持低温高湿（Toivonen and Forney, 2004; Jones et al., 2006）。然而，在制订合适的保持花椰菜质量的CA或MAP条件方面也已取得相当的成功，在设计条件下存储时间可达到空气中的两倍长（Jacobsson et al., 2004; Toivonen and Forney, 2004; DeEll et al., 2006）。Jacobsson（2004年）发现，以低密度聚乙烯薄膜，包含吸收乙烯的小包和5％O、7％CO包裹气氛用于花椰菜的MAP仓储，烹调的花椰菜就像新鲜蔬菜一样具有最好的的感官品质。 DeEll等（2006年）表明，包装中使用山梨糖醇配以高锰酸钾显著减少在0-1 ° C下29天中 MAP贮藏花椰菜发酵过的气味挥发物的积累。尽管这些良好的效果，但当O含量低于1％或CO超过10％时，总有恶臭的挥发性含硫化合物的潜在生成，尤其是甲硫醇和二甲基二硫化物，（Forney et al., 1991; Hansen et al., 1992; Di Pentima et al., 1995）。最近，作为对澄清CA如何延缓快速启动的收获诱导的花椰菜衰老的分子机制的第一步， Eason灯（2007年）采用差异显示分析，确定了一系列在10％的CO，5％的O 的CA的第一个24小时诱导生成的压力响应基因。 |
5楼2011-03-04 15:36:24
6楼2011-03-04 15:37:08
