鲜切水果的氧化

鲜切果蔬的质量同时受内在和外在因素的影响；内在因素也就是 代谢特性影响fresh-cut processing and storage，外在因素代表 环境状况且会抑制或加速内在因素的作用。
内在因素包括形态学、生理学、生化学上的防御机制，基因型， 应力诱发衰老机制和processing maturity；外在因素有贮藏温度、 湿度、cutting-knife sharpness和化学试剂。
Cultivar/genetic effects on the sensory and nutritional quality of fresh-cut fruits and vegetables have received considerable attention.
It has been well documented that different cultivars(品种) can vary widely in response to biotic and/or abiotic stresses and in bioactive components(e.g. Hodges et al., 1995, 1996, 1997;Hodges and Lester, 2006; Weston and Barth, 1997; Lee and Kader, 2000).
非生物因素对鲜切果蔬的质量和营养状况有重要 影响，而对于鲜切果蔬的加工、包装和储藏中的 非生物因素的定义和记录的相关研究较少。 很多指标可用来描述非生物因素的影响，如褐 变（鲜切果蔬的切口面）、呼吸加快、乙烯产 生、Vc含量降低、组织变软等
从文献评论可看出，目前对于非生物因素的 了解水平和机制是相对浅薄的。为能发展有 效的策略调整非生物因素对鲜切果蔬的质量 和营养影响，对此作进一步研究。
大部分的已发表的植物研究是关于非生物因素在生理、 生化或（和）基因表达方面对生长植物的影响。也有相 当一部分科学文献是关于生产、加工和采后对整果的影 响。很少一些是采前生产、加工技术、贮藏环境和包装 处理过程中非生物因素对鲜切果蔬的影响方面的。
对鲜切非生物影响的描述主要集中于现象而不是应力诱发 的机制，这篇综述也就主要参考各文献中的现象。这些鲜 切果蔬产品的症状包括褐变（尤其是鲜切面由组织损伤引 起的）、一系列氧化过程(Bhagwat et al.,2004) 、呼吸和 乙烯产生增加(Aguayo etal., 2004a) 、loss of flavour and texture (Lamikanra and Richard,2002), weight loss/dehydration (Piagentini et al., 2002), 营养素含量水平 降低如Vc(Gil et al., 2006)、developmentof off-odours (Beaulieu, 2006a)、membrane breakdown(Hodges et al., 2000), 和组织软化 (Aguayo et al.,2004a).
还有The sharpness of the cutting blade
The actual cutting process results in major tissue disruption as previously sequestered enzymes and substrates mix,hydrolytic enzymes are released and signaling-induced wounding responses may be initiated, as shown by Myung et al. (2006)for strawberries (Fragaria ananassa L.). 实际的切割过程导致之前隐蔽的酶和物质的混合、 水解酶的释放和损伤反应的启动对应的组织劣化。
低温贮藏过程中Temperature-induced injury、加工和包装 过程中的物理磨损并因此导致的abusive atmospheres or desiccation（干燥），这些都是非生物因素影响鲜切果蔬 生理和代谢特性并导致不友好的风味、组织、营养质量影 响产生的例子(Toivonen, 2003a) 。
Fra Baidu bibliotek
example
reported by Hong et al. (2000)
slices made from tomatoesthat were harvested from plants grown using hairyvetch（毛苕子） mulch were firmer, had lesswater-soaked areas (indicativeof chillingrelated injury), and exhibited less increases in electricalconductivity (indicator of stress-induced membrane damage)than slices from plants grown using black polyethylene（黑色聚乙烯 ） mulch.
非生物因素
Abiotic stress is defined as the negative impact of non-living factors on the living organisms in a specific environment. The nonliving variable must influence the environment beyond its normal range of variation to adversely affect the population performance or individual physiology of the organism in a significant way. biotic stress
Fresh-cut fruits and vegetablesdemonstrate increased respiration rates and wound-inducedethylene production, and increase the surface area per unit volume,thus exacerbating water loss (Toivonen and DeEll, 2002).
还有很多采前因素影响fresh-cut quality的例子，这只是其一
In another study, low light intensity resulted in shortened shelf-life of greenhouse grown long English cucumbers (Cucumis sativus L.) primary due to the fact that low light led to reduction in total chlorophyll content of the cucumber skin (Lin and Jolliffe, 1996)
The primary sources of abiotic stress, how fresh-cut produce responds to stresses, and how stress translates to quality decline of fresh-cut fruits and vegetables will be addressed in this review.
成熟度
Maturity of the harvested product can also influence its response to fresh-cut stress, thus emphasizing the fact that stress tolerance changes with maturity. The fresh-cut industry often prefers to process firmer and less mature fruit to improve shelf-life duration. For example, Gorny et al. (1998) found that although overripe peach and nectarine slices had a higher organoleptic sensory rating than mature green fruit, slices from the overripe fruit demonstrated significantly shorter shelf-life compared to less mature fruit based on visual quality.
3. Postharvest physical damage
Wounding，some form of processing (e.g. slicing, chopping, trimming整修, peeling,coring, and/or shredding切丝).
Cutting shape has also been identified as having an effect on quality of fresh-cut commodities, often in association with precut product turgidity. Cut cylinders of melon stored for up to 10 days were firmer than slices or trapezoidal（不规则） sections, but exhibited a higher degree of translucency（半透明） than the other two cuts; trapezoidal cutting was determined to be the optimal protocol （最佳方法)(Aguayo et al., 2004a).
Quality of fresh-cut fruits and vegetables as affected by exposure to abiotic stress
Postharvest Biology and Technology 48 (2008) 155–162
Agriculture and Agri-Food Canada Atlantic Food and Horticulture Research Centre，Pacific Agri-Food Research Centre
2. Preharvest stress effects and genetic factors
The postharvest quality of fruits and vegetables can be influenced by a large variety of preharvest and genetic factors, but it is generally accepted that produce which is stressed in the preharvest stage will invariably have reduced postharvest quality (Weston and Barth, 1997; Galvis-S′anchez et al., 2004; Calderon- Lopez et al., 2005).