摘要
真空预冷依据水在低压下的快速蒸发吸收材料自身热量达到降温目的,是实现园艺产品采后冷链无缝对接、减少贮藏流通损失、延长其货架期的重要环节。
温度是影响园艺产品品质的最主要因素之一。通常采用的检测园艺产品真空预冷过程温度的方法是把热电偶用胶带固定在材料上,该方法存在以下主要缺点:1)胶带阻碍水分的蒸发逸出,影响测温的准确性;2)对柔嫩组织,在不破坏表面结构的情况下准确测定其温度是很困难的;3)热电偶本身固有的局限性使每支热电偶每次只能检测与之接触表面上某一点的温度,而实际生产中又不可能布置无穷多的热电偶。另外,果蔬水分与其成分和微观结构之间存在复杂的束缚关系,真空预冷并不是理论上自由水的蒸发。真空压力下细胞内的水分状态和参与预冷程度如何,细胞膜系统和微观结构变化对水分汽化的作用如何,这些都是生产实际中遇到的根本问题。尤其对于细胞膜系统,需承受短时间的快速降压以及长时间的真空低压作用,膜系统是否被损伤或破坏尚无明确的研究结果。
鲜切花是深受人们喜爱的一种园艺产品,具备较高的经济价值,较好的社会效益和生态效益。花瓣、叶子、茎杆等部位的物性差异影响其真空预冷过程的温度变化以及瓶插过程的主要品质。洋葱内表皮由尺寸较大的具有典型植物细胞结构的单层细胞组成,是研究细胞形态变化有代表性的理想材料。可靠的温度检测有利于准确判定预冷终点、控制冷却过程、提高预冷效果。对细胞膜系统稳定性的研究有助于掌握真空预冷园艺产品的品质变化,为科学、深入开发真空预冷技术提供理论依据。研究内容分以下四部分:
一、利用热电偶检测鲜切花真空预冷过程温度变化,研究填充量和降压速率对月季切花预冷效果的影响。①发现不同数量花枝形成的局部环境对切花温度变化有明显影响(P<0.05)。10、50和120支处理切花不同部位温度变化和平均预冷终温不同,花束外围茎杆、叶子和花瓣的预冷终温均高于花束中心对应部位,花束中心区域的花朵花瓣预冷终温最低、降温速率最快。三种处理切花不同部位的温度变化显著区别于单支花,50支处理鲜重损失最小、瓶插寿命最长、预冷效果最好;②真空预冷可以不同程度地提高月季切花SOD、POD及CAT活性,有效地消除切花衰老过程中的活性氧,维持体内活性氧平衡以及细胞膜的稳定,延缓切花衰老进程;③不同降压速率(3.11×104 Pa min~(–1), 1.78×104 Pa min~(–1), 0.62×104 Pa min~(–1))对月季切花预冷品质有显著影响(P<0.05),且以中速降压(1.78×104 Pa min~(–1))处理对电导率、失重率、MDA和pH值的影响最小。
二、采用红外热成像技术对鲜切花真空预冷不同部位的温度分布和变化进行实时检测。结果表明:①月季切花不同部位的平均降温速率不同(内层花瓣最慢、外层花瓣最快、而叶子和茎杆无明显差异),内层花瓣的预冷终点温度是外层花瓣的3.1倍。非洲菊切花舌状花瓣的平均降温速率最快而茎杆最慢,茎杆的预冷终点温度是舌状花瓣的9.9倍。不论月季还是非洲菊切花,不同部位的冷却速率大小顺序在不同的预冷阶段表现不一致,各个部位不同区域的温度分布亦不均匀;②在相同预冷条件下,分别用红外和热电偶检测月季和非洲菊切花温度,红外检测温度比热电偶检测温度分别低2.06–4.50°C和4.55~(–1)0.4°C。说明热电偶检测受固定方法、位置和水汽化的影响较大;③月季外层花瓣和非洲菊舌状花瓣的外缘为易发生冻伤部位。这就要求在鲜切花真空预冷过程中密切监测不同部位特别是花瓣外缘的温度变化,在保证预冷效果的同时避免冷伤发生;④月季和非洲菊单支花在瓶插期间的鲜重、气孔导度和蒸腾速率变化率均小于花束,平均预冷终点温度低于花束,瓶插寿命长于花束。延迟预冷对切花品质影响显著(P<0.05)。随延迟时间增加,预冷终点温度不断升高,瓶插寿命显著降低(P<0.05),花束主要品质受延迟时间的影响程度大于单支花。在本实验条件下,室温存放10 h,两种切花均失去市场价值。
三、研究成膜型抗蒸腾剂对鲜切花真空预冷效果的影响。喷施抗蒸腾剂之后进行瓶插实验可以降低切花失水、延缓花朵开放进程、降低气孔导度、减少丙二醛积累、维持细胞膜完整性,切花寿命比直接进行瓶插实验延长32%。抗蒸腾剂和真空预冷的联合使用在快速去除田间热的同时有效地解决了水分损失过多的问题。其中,先喷施抗蒸腾剂再进行真空预冷处理的月季切花,其瓶插实验效果明显优于真空预冷后再进行抗蒸腾剂处理的切花(P<0.05),切花寿命比后者增加了12%。
四、研究真空预冷对组织微观结构和物性的影响。①初步证实真空处理对洋葱表皮微观结构造成了较大的影响;②细胞膜系统在短时间内承受着快速降压和水分蒸发迁移微应力,液泡和细胞膜损伤导致胞内水分蒸发损失,从微观层面解释了组织水分过度损失的原因;③同时研究发现,膜损伤造成了花色素苷和电解质流失,导致细胞颜色减退以及电导率升高。质膜和细胞壁之间的间隙随真空室压强降低呈现先减小后增大的趋势;④扫描电镜观察显示细胞表面形态、细胞壁和胞间层发生了不同程度的形变,直接导致表皮组织抗张强度的降低;⑤改变降压速率对洋葱表皮细胞表面形态、质膜和细胞壁间距、水分损失、相对电导率、颜色和机械性能有明显影响(P<0.05)。在慢速和快速降压条件下,微观结构和物理性质发生了较大变化,而中速降压处理引起的破坏作用很小。
本文采用宏观和微观研究相结合,实时图像分析与理化指标检测相结合的方法,分析比较红外热成像和传统热电偶温度检测结果及其对鲜切花后续贮藏特性的影响,解决鲜切花真空预冷过程温度难以准确检测和预冷终点难以判定的问题,并深入研究真空预冷压力变化对微观组织结构尤其是细胞膜系统的作用程度。
The principle of vacuum cooling is based on rapid evaporation of part of the moisture of the product under vacuum. The latent heat of product itself is moved and cooling is achieved. Vacuum cooling is a key link of the implementation of seamless joint of post harvest horticultural products, the loss reduction of storage and transportation and the shelf-life extension.
One of the most important factors affecting the quality of horticultural crops is temperature. In previous papers, thermocouples were secured by tapes to measure the temperature. There are three major disadvantages to thermocouple temperature measurement:①causing a restriction in the escape of water vapor, which certainly affects the microclimate around the thermocouple.②It is very difficult to measure the petal temperature without damaging the thin fragile membrane with the thermocouple.③The inherent limitation of thermocouple is that each thermocouple can measure temperature only at the point on a surface that it is contacting. It is impractical to use more than a small number of thermocouples.
Moreover, there has been little information about biological study, especially for cell membrane system and microstructure changes during vacuum cooling. There is a complex binding relationship between the moisture, constituents and microstructure of materials. The water evaporation during vacuum cooling is not the theoretical evaporation of free water. There are several practical productive problems such as how do the states and participation level in cooling of intracellular moisture, how does the effect on water vaporization affected by the changes of cell membrane system and microstructure. Especially to membrane system, which was subject to rapid pressure reduce in a short time and influenced by water evaporation and a long time vacuum environment. It was not clear whether the changes of pressure and forces could damage the cell membrane system.
Cut flower is a very popular horticultural product, with high economic value, good social and ecological benefits. Different physical properties of petals, leaves and stems of flowers affect the temperature changes during vacuum cooling and the main quality during vase period. Onion epidermis composed by a single layer cells with large size and typical plant cell structure is an ideal material to study the changes in cell morphology. The reliable temperature measurement is beneficial to the judgment of pre-cooling end-temperature, control of cooling processes, and improvement of pre-cooling effects. The understanding and mastering of the mechanism of vacuum cooling is helpful for the scientific and deep development of vacuum cooling.
The main research part can be divided into four parts as follows:
1. Thermocouples were applied to measure the temperatures of cut flowers during vacuum cooling, and study the effects of loading and pressure reduction rates on the pre-cooling effects of cut roses.①The local environment made by different amounts of flowers had obviously influence (P<0.05) on the temperature especially for the inner parts of cut flowers. Though the temperature changes and average pre-cooling end-temperatures for different parts of 10, 50 and 120 flowers, the end-temperatures of external parts were higher than internal parts, the end-temperature of the internal petals were the lowest and the temperature reduction rates were the fastest. There were big differences between the individual flower and other three treatments. The fresh weight loss of 50 flowers treatment was the smallest and its vase life was the longest.②The activities of SOD, POD and CAT were improved. Consequently, the active oxygen produced during the aging process of cut flower was scavenged effectively, and the balance of active oxygen in vivo and the stability of cell membrane were maintained.③Different pressure reduction rates (3.11×104 Pa min~(–1), 1.78×104 Pa min~(–1), 0.62×104 Pa min~(–1)) had significant effects (P<0.05) on the pre-cooling quality of cut roses. The moderate pressure reduction rate had the smallest influence on relative electrical conductivity, weight loss, MDA and pH.
2. Thermal infrared imaging was used to realize the real-time measurement of the distributions and changes of temperatures of cut flowers, and compared with the results made by thermocouples.①Thermal infrared imaging showed that the average cooling rates of different parts of the rose were different (the slowest was the inner petals, the fastest was the outer petals, and there were no remarkable differences between the leaf and the stem) , the final temperature of cooling of the inner petal was 3.1 times higher than that of the outer petal. For cut gerberas, the fastest was the ligule-shape petal, and the slowest was the stem, the final temperature of cooling of the stem was 9.9 times higher than that of the ligule-shape petal. The sequences of cooling rates of different parts of rose and gerbera flowers during different cooling stages were different, and the temperature distributions of different parts measured with thermal infrared camera were non-uniform.②Under the same pre-cooling conditions, the temperatures detected by the thermal infrared imaging were ac. 2.46 to 4.50°C and 4.55 to 10.4°C lower than the results measured by thermocouples of cut rose and gerbera flowers, respectively. The results showed that thermocouple temperature measurement was affected by fixation method, location and water vapor.③The parts which chilling injury occurred easily were the outside edges of outer petals of cut roses and ligule-shape petal of gerbera flowers. In order to obtain better pre-cooling effects without chilling injury, temperatures of the different parts of cut flowers especially for the outside edges of outer petals must be monitored closely during vacuum cooling.④The changes of relative fresh weight, stomatal conductivity and transpiration of the individual flowers were bigger than bunches of flowers for both cut roses and gerberas. The average pre-cooling end-temperatures of bunches of flowers were higher than the individual flowers. Not only direct but also delay pre-cooling of cut roses and gerberas, the vase life of bunches of flowers were shorter than the individual flowers. Furthermore, the vase life of individual and bunches of flowers were decreased obviously (P<0.05) with time during vase period. In this experiment, two kinds of flowers lost their ornamental values after ten hours storage at room temperature.
3. Effects of antitranspirant and vase solution on the quality of cut flowers were studied. Spray application of antitranspirant decreased the fresh weight loss, delayed the process of flowering, slowed down the decrease rate of stomatal conductivity, decreased transpiration and the accumulation of MDA and maintained the integrity of cell membrane. The vase life was extended by 32% compared with the control flowers. The combined use of antitranspirant and vacuum cooling could effectively improve the pre-cooling quality. Furthermore, the experimental effects of spraying antitranspirant followed by vacuum cooling were better than the treatment of vacuum cooling followed by the application of antitranspirant (P<0.05), and the vase life was extended by 12% compared with the treatment of vacuum cooling followed by the application of antitranspirant.
4. Effect of vacuum treatment on microstructure and physical properties of tissue.①The present study has shown that vacuum treatment induced the changes of onion epidermis microstructure.②For cellular membrane system, which was subject to rapid pressure reduce in a short time and influenced by microstress caused by water evaporation. Surface morphology and that cell rupture occurred result from the joint effects of water loss and pressure gradient. The vacuole and cell membranes were damaged which led to loss of intracellular water, which explained the reason for excessive loss of tissue water at micro-level. It presented preliminary proof of the excessive water loss induced by vacuum treatment.③Disruption and damage to cell membranes altered permeability led to the loss of electrolyte and anthocyanin, resulting in fade in cellular color and increase of electrical conductivity. The spaces between the membrane and cell wall decreased first and then increased with the decreasing of pressure in vacuum chamber.④SEM micrographs indicated that vacuum treatment induced significant changes on cell surface morphology, cell wall and intercellular layers of onion epidermis, which led to the decrease of tensile strengths of epidermal tissue.⑤Changed the pressure reduction rate had obvious effects on the surface morphology, spaces between the cell membrane and cell wall, mass, REC, color, and mechanical properties. Of the 3 pressure reduction rates, treatments at the slow and fast pressure reduction rates led to remarkable effects on the cell membrane integrity of the onion epidermis, while treatment at the medium pressure reduction rate caused less damage.
This paper adopts the method of combination of macro-and microscopic, and the combination of real-time image analysis and detection of physiochemical indexes. The effects of temperature changes measured by thermal infrared imaging and thermocouples during vacuum cooling on the storing properties of cut flowers were analyzed and compared, so as to overcome some shortcomings such as the difficulties of temperature detection and pre-cooling end-temperature judgment of cut flowers during vacuum cooling. Furthermore, the impacts of vacuum cooling on the microstructure, especially for cell membrane system were studied.
引文
1 McDonald K and Sun D W. Vacuum cooling technology for the food processing industry: a review. Journal of Food Engineering, 2000, 45, 55–65
2 http://www.bonipak.com/reg/operations/cold_storage.html
3 Sullivan G H, Davenport L R and Julian J W. Progress in new crops: Precooling: key factor for assuring quality in new fresh market vegetable crops. Arlington (VA): ASHS Press, 1996
4 Thompson A K. Postharvest technology of fruit and vegetables. London: Blackwell Science Ltd., 1996
5 Reid M S and Kofranek A M. Post-harvest physiology of cut flowers. Chronica Horticulturae, 1980, 20(2), 25–27
6 Ohling R. Rapid air precooling of fruits and vegetables. ASHRAE Journal, 1990, 3, 60–65
7 Paull R E. Effect of temperature and relative humidity on fresh commodity quality. Postharvest Biology and Technology, 1999, 15, 263–277
8 Shewfelt R L and Dixon P R. Seven principles for better quality of refrigerated fruits and vegetables. In Refrigeration Science and Technology Proceedings, New Developments in Refrigeration for Food Safety and Quality, Lexington, Kentucky, USA, 1996, 210–221
9 Brosnan T and Sun D W. Pre-cooling technique and application for horticultural Products-a review. International Journal of Refrigeration, 2001, 24, 154–170
10 Winkler A J, Cook J A, Kliewer W M, et al. General viticulture, Berkley: University of California Press, 1974
11 Mitchell F G, Mayer G, Maxie E C, et al. Cold storage effects on fresh market peaches, nectarines, and plums:1) estimating freezing points; 2) using low temperature to delay internal breakdown, California Agriculture, 1974, 28, 12–14
12 Hernandez-Rivera L, Mullen R and Cantwell M. Textural changes of asparagus in relative to delays in cooling and storage conditions. HortTechnology, 1992, 2, 378–381
13杜玉宽,杨德兴.水果蔬菜花卉气调贮藏及采后技术.中国农业大学出版社,北京, 2000
14王如林,夏睿.真空预冷技术的开发和应用. 21世纪中国食品冷藏链大会暨速冻食品发展研讨会论文集, 1998, 75–77
15韩志,谢晶,徐世琼.真空预冷技术在果蔬保鲜体系中的应用.冷藏技术, 2005, 112(3), 6–9
16王海鸥,姜松.真空冷却技术及其在食品工业的研究和应用.制冷, 2004, 23(l), 33–36
17孙恒,张洁,祁照岗等.真空预冷工艺的实验研究.食品科技, 2003(3), 26–28
18 Wang L J and Sun D W. Rapid cooling of porous and moisture food by using cooling technology. Trends in Food Science and Technology, 2001, 12(5), 174–184
19杜建通,申江,陈天及.日本蔬菜预冷技术的发展与现状.制冷, 1999, 3, 36–38
20邹同华.果蔬真空预冷过程及捕水器特性的研究[博士学位论文].天津,天津大学, 2004
21翟家佩,苏树强.果蔬真空预冷装置的设计与研究.真空, 2001, 2, 25–29
22沈炜.蔬菜真空预冷保鲜设备设计探讨.江西农业学报, 2008, 20(5), 73–74
23严雷,刘斌,邹同华.真空预冷中捕水器与真空泵的优化匹配研究.制冷学报, 2006, 27(1), 49–52
24张芳芳,韩厚德.真空预冷与冷冻干燥中捕水器的不同结构与特点浅析.真空与低温, 2007, 13(1), 52–56
25贺素艳,王德昌,马永志.真空预冷实验装置计算机检测系统.农业机械学报, 2009, 40(10), 111–113
26刘洋,申江,邹同华,等.数据采集处理系统在真空预冷实验中的应用.制冷, 2005, 24(1), 43–45
27 Haas E and Gur G. Factor affecting the cooling rate of lettuce in vacuum cooling installations. International Journal of Refrigeration, 1987, 10(2), 82–86
28 Martínez J A and Artés F. Effect of packaging treatments and vacuum-cooling on quality of winter harvested iceberg lettuce. Food Research International, 1999, 32(9), 621–627
29 Ozturk H M and Ozturk H K. Effect of pressure on the vacuum cooling of iceberg lettuce International Journal of Refrigeration, 2009, 32(3), 402–410
30 Cheng H P and Hsueh C F. Multi-stage vacuum cooling process of cabbage. Journal of Food Engineering, 2007, 79(1), 37–46
31王璐,董庆利,李保国,等.不同真空预冷处理条件对鲜切芹菜品质的影响.食品与发酵工业, 2010, 36(2), 193–196
32李素云,纵伟,吴柳柳.不同真空预冷压力对生菜储藏质量的影响.真空, 2010, 47(1), 83–85
33陈羽白,林海英,赵华海,等.菜心真空预冷效果的试验研究.农业工程学报, 2003, 19(5), 161–165
34刘洋,李砚泉,申江.结球白菜干耗的真空预冷实验研究.制冷学报, 2007, 28(1), 18–21
35张哲平,宋小勇,李云飞.红外热成像技术在研究不同果蔬真空预冷特性中的应用.科技通报, 2009, 25(3), 295–304
36刘芬,张爱萍,刘东红.真空预冷处理对青花菜贮藏期间生理活性的影响.农业机械学报, 2009, 40(10), 106–110
37石小琼,邓金星,张映斌.真空预冷技术在子芋冷藏保鲜上的应用研究.农业工程学报, 2001, 17(4), 86–90
38李文香,张慜,陶菲.真空预冷结合减压贮藏保鲜水蜜桃.食品与生物技术学报, 2005, 24(5), 42–46
39李文香,张慜,陶菲.真空预冷终温对草莓短期保鲜贮藏的影响.食品与生物技术学报, 2006, 25(4), 72–76
40刘斌,邹同华.真空槽内不同装载率对真空预冷效果的影响.天津大学学报, 2007,
40(10), 1171–1175
41申江,刘洋,邹同华.几种蔬菜真空预冷的对比实验研究.制冷学报, 2005, 26(3), 11–15
42陈威,丁伟华.几种蔬菜真空预冷过程的实验研究.食品科技, 2010, 35(3), 56–59
43 Noble R H. Review of vacuum cooling of mushroom. Mushroom Joumal, 1985, 149, 168–170
44 McDonald K, Sun D W and Kenny T. Comparison of the quality of cooked beef products cooled by vacuum cooling and by conventional cooling. Lebensmittel-Wissenschaft und-Technologie, 2000, 33(1), 21–29
45 Wang L J and Sun D W. Experimental evaluation of the performance of vacuum cooling method for large cooked meat joints. Journal of Food Process Engineering, 2002, 25, 455–472
46 Jackman P, Sun D W and Zheng L Y. Effect of combined vacuum cooling and air blast cooling on processing time and cooling loss of large cooked beef joints. Journal of Food Engineering, 2004, 81(1), 266–271
47 Mc Donald K and Sun D W. The formation of pores and their effects in a cooked beef product on the efficiency of vacuum cooling. Journal of Food Engineering, 2001, 47(3), 175–183
48 Mc Donald K, Sun D W and Lyng J G. Effect of vacuum cooling on thethermophysical properties of a cooked beef product. Journal of Food Engineering, 2002, 52(2), 167–176
49 Sun D W and Wang L J. Experimental investigation of performance of vacuum cooling for commercial large cooked meat joints. Journal of Food Engineering, 2004, 61(4), 527–532
50 Hou?ka M, Landfeld A and Sun D W. Eating quality enhancement of cooked pork and beef by ripening in brine and vacuum cooling. Journal of Food Engineering, 2005, 68(3), 357–362
51 Mc Donald K and Sun D W. Effect of evacuation rate on the vacuum cooling process of a cooked beef product. Journal of Food Engineering, 2001, 48(3), 195–202
52 Sun D W and Hu Z H. CFD simulation of coupled heat and mass transfer through porous foods during vacuum cooling process. International Journal of Refrigeration, 2003, 26(1), 19–27
53 Sun D W and Wang L J. Development of a mathematical model for vacuum cooling of cooked meats. Journal of Food Engineering, 2006, 77(3), 379–385
54 Wang L J and Sun D W. Modelling vacuum cooling process of cooked meat–part 2: mass and heat transfer of cooked meat under vacuum pressure. International Journal of Refrigeration, 2002, 25(7), 862–871
55 Wang L J and Sun D W. Modelling vacuum cooling process of cooked meat–part 1: analysis of vacuum cooling system. International Journal of Refrigeration, 2002, 25(7), 854–861
56 Sun D W and Hu Z H. CFD predicting the effects of various parameters on core temperature and weight loss profiles of cooked meat during vacuum cooling. Computers and Electronics in Agriculture, 2002, 34(1–3), 111–127
57 Wang L J and Sun D W. Effect of operating conditions of a vacuum cooler on cooling performance for large cooked meat joints. Journal of Food Engineering, 2004, 61(2), 231–240
58 Schmidt F C, Arag?o G M F and Laurindo J B. Integrated cooking and vacuum cooling of chicken breast cuts in a single vessel. Journal of Food Engineering, 2010, 100(2), 219–224
59 Jin T X. Experimental investigation of the temperature variation in the vacuum chamber during vacuum cooling. Journal of Food Engineering, 2007, 78(1), 333–339
60 Jin T X and Xu L. Numerical study on the performance of vacuum cooler and evaporation-boiling phenomena during vacuum cooling of cooked meat. EnergyConversion and Management, 2006, 47(13–14), 1830–1842
61 Jin T X and Xu L. Development and validation of moisture movement model for vacuum cooling of cooked meat. Journal of Food Engineering, 2006, 75(3), 333–339
62马志英.真空冷却技术在熟肉制品工业化生产中的应用研究.食品科学, 2003, 24(10), 110–113
63李素云,纵伟,李昌文.真空预冷技术及其在肉类产品中的应用.肉类研究, 2009, 6, 85–88
64蒋其斌,张克俭,廖敏.食品真空冷却技术的应用研究.食品工业科技, 2004, 25(7), 68–70
65张青,陈椒.真空冷却及真空包装保鲜工艺在鲜肉贮藏中的实验研究.冷藏技术, 2001, 4, 1–5
66黄壮霞,张慜,朱丹实,等. MAP结合真空预处理延长鲜牛肉货架期.食品与生物技术学报, 2005, 24(3), 22–26
67 Carver C II. Vacuum cooling and thawing fishery Products. Marine Fisheries Review National Oceanic and Atmospheric Administration, Washington, USA. 1975
68丁伟华.上海海事大学硕十学位论文. 2007, 6
69 Burton K S, Frost C E and Atkey P T. Effect of vacuum cooling on mushroom browning. Intemational Journal of Food Science and Teclmology, 1987, 22(6), 599–606
70 Lane W C. Pre-packaging and marketing of fresh mushrooms. Mushroom Science, 1972, (8), 763–775
71陶菲,郜海燕,张慜,等.白蘑菇真空预冷工艺的研究.食品与机械, 2009, 25(4),
41–44
72陶菲,张慜,余汉青,等.不同真空预冷终温对双抱蘑菇保鲜的影响.食品与生物技术学报, 2005, 24(3), 39–43
73 Tao F, Zhang M and Yu H Q. Effect of vacuum cooling on physiological changes in the antioxidant system of mushroom under different storage conditions. Journal of Food Engineering, 2007, 79(4), 1302–1309
74 Tao F, Zhang M, Yu H Q, et al. Effects of different storage conditions on chemical and physical properties of white mushrooms after vacuum cooling. Journal of Food Engineering, 2006, 77(3), 545–549
75石小琼,邓金星,张映斌.真空预冷技术在茶树菇冷藏保鲜上的应用研究.制冷学报, 2001, 3, 41–44
76高俊平,孙自然,周山涛.真空预冷促进月季切花吸收保鲜剂.制冷学报, 1995, 4,30–34
77高俊平,孙自然,郭康.提高切花真空预冷效果的技术措施.农业工程学报, 1996, 12(4), 194–198
78孙万福,唐雨,唐北育.花卉真空预冷保鲜技术探讨.真空, 2002, 8, 39–42
79陈家盛,宋小勇,李云飞.填充量对月季切花真空预冷主要品质的影响.上海交通大学学报(农业科学版), 2010, 28(1), 76–81
80 Brosnan T and Sun D W. Compensation for Water loss in vacuum–precooled cut lily flowers. Journal of Agricultural Engineering Research, 2001, 79(3), 299–305
81 Brosnan T and Sun D W. Influence of modulated vacuum cooling on the cooling rate, mass loss and vase life of cut lily flowers. Biosystems Engineering, 2003, 86(1), 45–49
82 Sun D W and Brosnan T. Extension of the vase life of cut daffodil flowers by rapid vacuum cooling. International Journal of Refrigeration, 1999, 22, 472–478
83 Landfeld A, Houska M, Kyhos K, et al. Mass transfer experiments on vacuum cooling of selected pre-cooked solid foods. Journal of Food Engineering, 2002, 52(3), 207–210
84 Zhang Z H and Sun D W. Effect of cooling methods on the cooling efficiencies and qualities of cooked broccoli and carrot slices. Journal of Food Engineering, 2006, 77(2), 320–326
85 Zhang Z H and Sun D W. Effects of cooling methods on the cooling efficiency and quality of cooked rice. Journal of Food Engineering, 2006, 77(2), 269–274
86 Everington D W. Vacuum technology for food Processing. Food Technology International Europe, 1993, 18, 71–74.
87 Primo-Martin C, de Beukelaer H and Hamer R J. Fracture behavior of bread crust: Effect of bread cooling conditions. Journal of Food Engineering, 2008, 89, 285–290
88 James S T. Secondary chilling of meat and meat products. In meat refrigeration–why and how? UK: University of Bristol, 1994, 1–4
89 Dirisio T. Vacuum cooling in food processing. Prepared Foods, 1990, 159, 195–197
90 Self K P, Nute G R, Burfoot D, et al. Effect of pressure cooking and pressure rate change during cooling in vacuum on chicken breast quality and yield. Journal of Food Science, 1990, 55, 1531–1535, 1551
91 Rennie T J, Raghavan G S V, Vigneault C and Gariepy Y. Vacuum cooling of lettuce with various rates of pressure reduction. Transactions of the ASAE, 2001, 44, 89–93
92 Rennie T J, Vigneault C, Raghavan GSV and DeEll J R. Effects of pressure reduction rate on vacuum cooled lettuce quality during storage. Canadian BiosystemsEngineering, 2001, 43, 339–343
93 Zheng L Y and Sun D W. Vacuum cooling for the food industry–a review of recent research advances. Trends in Food Science & Technology, 2004, 15, 555–568
94申江,张于峰,邹同华,等.津产结球白菜真空预冷试验研究.农业机械学报, 2006, 37(8), 86–88
95 Rennie T J, Raghavan G S V and Vigneault C. Determination of the product refrigeration load in vacuum cooling of lettuce. Applied Engineering in Agriculture, 2000, 16, 459–464
96 Dost?l M and Petera K. Vacuum cooling of liquids: mathematical model. Journal of Food Engineering, 2003, 61, 533–539
97 Tan H, Liu X H, Ma N, et al. Ethylene-influenced flower opening and expression of genes encoding Etrs, Ctrs, and Ein3s in two cut rose cultivars. Postharvest Biology and Technology, 2006, 40, 97–109
98 Ozturk H M and Ozturk H K. Effect of pressure on the vacuum cooling of iceberg lettuce. International Journal of Refrigeration, 2008, 9, 1–9
99 Xue J Q, Yang F and Gao J P. Isolation of Rh-TIP1;1, an aquaporin gene and its expression in rose flowers in response to ethylene and water deficit. Postharvest Biology and Technology, 2009, 51, 407–413
100 Cheng H P. Vacuum cooling combined with hydrocooling and vacuum drying on bamboo shoots. Applied Thermal Engineering, 2006, 26, 2168–2175
101 He S Y and Li Y F. Theoretical simulation of vacuum cooling of spherical foods. Applied Thermal Engineering, 2003, 23, 1489–1501
102 He S Y, Feng G P, Li Y F, et al. Effects of pressure reduction rate on quality and ultrastructure of iceberg lettuce after vacuum cooling and storage. Postharvest Biology and Technology, 2004, 33(3), 263–273
103 James S J, Burfoot D and Bailey C. The engineering aspects of ready meal production. In: Field, R.W., Howell, J.A., Process Engineering in the Food Industry Developments and Opportunities, 1. Elsevier Applied Science, London, 1989, 43–58
104 Bailey C. Food refrigeration–current technology and future options. Food Science and Technology Today, 1993, 8(1), 24–31
105 Rennie T J, Vigneault C, Raghavan G S U and DeEll J R. Effects of pressure reduction rate on vacuum cooled lettuce quality during storage. Canadian Biosystems Engineering, 2001, 43, 339–344
106中国花卉统计数据表(花卉产销情况).中华人民共和国农业部
107李彤.提升我国花卉出口竞争力的对策研究.经济论坛, 2008, 8, 49–50
108李倩,金彦平.我国花卉出口中存在的主要问题及其对策.科技经济市场, 2006, 87–89
109出口商品技术指南(花卉).中华人民共和国商务部, 2006, 6–12
110 http://www.dnflower.com/integrate.php?iid=177&ig=special
111陆燃.云南花企重视鲜花保鲜.中国花卉园艺, 2006, 15, 30
112 Anabel E.海运将成为今后切花的运输方式之一.环球, 2008, 3, 50–51
113 Yamamoto K, Komatsu Y, Yokoo Y, et al. Delaying flower opening of cut roses by cis-propenylphosphonic acid. Journal of the Japanese Society for Horticultural Science, 1994, 63, 159–166
114 Muller R, Lind-Iversen S, Stummann B M, et al. Expression of genes for ethylene biosynthetic enzymes and an ethylene re-ceptor in senescing flowers of miniature potted roses. Journal of Horticultural Science and Biotechnology, 2000, 75, 12–18
115 Hu Y, Doi M, Imanishi H. Competitive water relations between leaves and flower bud during transport of cut roses. Journal of the Japanese Society for Horticultural Science, 1998, 67, 532–536
116 Leonard R T, Nell T A, Suzuki A, et al. Evaluation of long term transport of Colombian grown cut roses. Acta Horticulturae, 2001, 543, 293–297
117 Serrano M, Martinez G, Pretel M T, et al. Cold storage of rose flowers (Rosa hybrida, cultivar‘Visa’): physiological alterations. Scientia Horticulturae, 1992, 51, 129–137
118 Ueda Y, Nishihara S, Tomita H, et al. Photosynthetic response of Japanese rose species Rosa bracteata and Rosa rugosa to temperature and light. Scientia Horticulturae, 2000, 84, 365–371
119何生根.切花品质的生理生化基础.植物生理学通讯, 1997, 33(1), 66–70
120李金洪,李伯航.植物抗蒸腾剂的研究与应用.中国农学通讯, 1993, 9(4), 28–31
121冯建灿,郑根宝,何威,等.抗蒸腾剂在林业上的应用研究进展与展望.林业科学研究, 2005, 18(6), 755–760
122吴美华,万水林,徐娟,等.抗蒸腾剂应用于赣南脐橙试验初报.江西农业学报, 2009, 21(8), 91–92
123李茂松,李森,张述义,等.一种新型FA抗蒸腾剂对春玉米生理调节作用的研究.中国农业科学, 2003, 36(11), 1266–1271
124汪劲松,姚翔翔.三种保鲜剂对延缓须苞石竹切花衰老的影响.湖北师范学院学报(自然科学版), 2003, 23(1), 58–60
125罗红艺,李金枝,景红娟.含多效唑保鲜剂对非洲菊切花的保鲜效应.湖北农业科学, 2003, 9(5), 80–81
126林艳,赵晓芩.月季切花组培苗微插生根主要因素的探讨.河北林业科技, 1998(3), 16–17
127施满容.切花衰老的控制措施.闽东农业科技, 1999(2), 23–24
128武应霞,林春阳,冯建灿,等.不同抗蒸腾剂对月季切花保鲜的影响.中国农学通报, 2009, 25(2), 152–155
129明红.热电偶不稳定性影响因素及测试方法.计量与测试技术, 2010, 37(8), 16–17
130李云红,孙晓刚,杨幸芳,等.红外热像仪测温精度的理论分析.西安工程科技学院学报, 2007, 21(5), 635–639
131黄树青,李宁,顾卫.热红外热像仪测量温度的误差分析和修正.气象科学, 2007, 12, 1–6
132 Guilioni L, Jones H G, Leinonen I, et al. On the relationships between stomatal resistance and leaf temperatures in thermography. Agricultural and Forest Meteorology, 2008, 148(11), 1908–1912
133 Kim Y and Ling P P. Machine vision guided sensor positioning system for leaf temperature assessment. Transactions of the ASAE,2001, 44(6), 1941–1947
134 Jones H G. Application of thermal imaging and infrared sensing in plant physiology and ecophysiology. Advances in Botanical Research, 2004, 41, 107–163
135赵匀,武传宇,胡旭东.农业机器人的研究进展及存在的问题.农业工程学报, 2003(1), 20–24
136徐惠荣,应义斌.红外热成像在树上柑桔识别中的应用研究.红外与毫米波学报, 2004, 23(5), 353–355
137 Wen Z and Tao Y. Dual-camera NIR/MIR imaging for stem-end/calyx identification in apple defect sorting. Transaction of the ASAE, 2000, 43(2), 449–452
138 Varith J, Hyde G M, Baritelle A L, et al. Non-contact bruise detection in apples by thermal imaging. Innovative Food Science & Emerging Technologies, 2003, 4(2), 211–218
139 Baranowski P, Lipecki J, Mazurek W, et al. Detection of watercore in‘Gloster’apple using thermography. Postharvest Biology and Technology, 2008, 47(3), 358–366
140 Bulanon D M, Burks T F and Alchanatis V. Study on temporal variation in citrus canopy using thermal imaging for citrus fruit detection. Biosystems Engineering, 2008, 101(2), 161–171
141 Fuller M P and Wisniewski M. The use of infrared thermal imaging in the study of ice nucleation and freezing of plants. Journal of Thermal Biology, 1998, 23(2), 81–89
142 Ginesu G, Giusto D D, M?rgner V, et al. Detection of foreign bodies in food by thermal image processing. IEEE Transactions on Industrial Electronics, 2004, 51(2), 480–490
143 Fito P J, Ortola M D, De los Reyes R, et al. Control of citrus surface drying by image analysis of infrared thermography. Journal of Food Engineering, 2004, 61, 287–290
144张志良.植物生理学实验指导.北京:高等教育出版社出版. 1999, 88–91
145林植芳,李双顺.水稻叶片衰老与SOD活性及脂质过氧化作用的关系.植物学报, 1984, 26(6), 605–615
146 Beauchamp C and Fridovich I. Superoxide dismutase: improved assays and an assay applicable to acrylamide gels. Analytical biochemistry. 1971, 44, 276–287
147 Chance B. and Maehly A C. Assay of catalase and peroxidase. Methods in Enzymology, 1995, 2, 764–775
148 Faragher J D and Mayak S. Physiological responses of cut flowers to exposure to low temperature: Changes in membrane permeability and ethylene production. Journal of Experimental Botany, 1984, 35, 965–974
149高勇,吴绍锦.月季(Ladgx)切花水分、鲜重变化和瓶插寿命的相关性研究初报.南京农业大学学报, 1989, 12(3), 87–88
150汪羞德,顾永明.不同溶液对瓶插唐菖蒲水分平衡及保鲜技术.上海农业科技, 1985, 6, 16–17
151韩卫民,王丙举,李荣,等.不同保鲜剂对一枝黄切花保鲜效果的研究.北方园艺, 2000, 5, 35
152高俊平,孙自然,周山涛.月季切花真空预冷水分损失与补充的研究.园艺学报, 1994, 21(4), 381–385
153新堀二千男.切花冷链流通,预冷技术.食品流通技术(日), 1993, 12–18
154王爱国,罗广华.丙二醛作为植物膜脂过氧化指标的探讨.植物生理学通讯, 1986, 1, 1–7
155 VanDoom W G. Water relations of cut flowersΠ. Some species of tropical provenance. Acta Horticulturae, 1999, 482, 65–69
156 Doi M, Reid M S. Sucrouse improves the postharvest life of cut flowers of a hybridliimonium. Hort Science, 1995, 30(5), 1058–1060
157苏军,叶文.含抗坏血酸保鲜剂对小苍兰切花几个衰老指标的影响.上海农业学报, 1997, 13(4), 80–82
158薛秋华,林如.月季切花衰老与含水量、膜脂过氧化及保护酶活性的关系.福建农业大学学报, 1999, 28(3), 304–308
159李永红,张常青,谭辉,等.抗氧化剂对月季切花失水胁迫耐性和SOD、POD活性的影响.中国农业大学学报, 2003, 8(5), 14–17
160 Shomer I, Borochov–Neori H, Luzki B, et al. Morphological, structural and membrane changes in frozen tissues of Madjhoul date (Phoenix dactylifera L.) fruits. Postharvest Biology and Technology, 1998, 14, 207–215
161 Halevy A H and Mayak S. Senescence and postharvest physiology of cut flower. Horticultural Reviews, 1979, 1, 204–236
162 Yamada K, Ito M, Oyama T, et al. Analysis of sucrose metabolism during petal growth of cut roses. Postharvest Biology and Technology, 2007, 43, 174–177
163 Pompodakis N E, Terry L A, Joyce D C, et al. Effect of seasonal variation and storage temperature on leaf chlorophyll fluorescence and vase life of cut roses. Postharvest Biology and Technology, 2005, 36, 1–8
164 Torre S and Fjeld T. Water loss and postharvest characteristics of cut roses grown at high or moderate relative air humidity. Scientia Horticulturae, 2001, 889, 217–226
165 Reid M S. Gerbera and Transvaal Daisy. Department of Plant Sciences, 2004, University of California, Davis, CA 95616
166 Sun D W and Zheng L Y. Vacuum cooling technology for the agri–food industry: Past, present and future. Journal of Food Engineering, 2006, 77, 203–214
167 Jin J S, Shan N W, Ma N, et al. Regulation of ascorbate peroxidase at the transcript level is involved in tolerance to postharvest water deficit stress in the cut rose. Postharvest Biology and Technology, 2006, 40, 236–243
168 Jones R B, Serek M and Reid M S. Pulsing with Triton X-100 improves hydration and vase life of cut sunflowers (Helianthus annuus L.). HortScience, 1993, 28, 1178–1179
169 King A I and Reid M S. Diurnal chilling sensitivity and desiccation in seedlings of tomato. Journal of the American Society for Horticultural Science, 1987, 112, 821–824
170 Fraser H W. Sizing and layout of a short–term refrigerated storage for fruits and vegetables. Factsheet. Ontario Ministry of Agriculture, Food and Rural Affairs, 1 Stone Road West, Guelph, 1992
171 Halevy A H, Byrne T G, Kofranek A M, et al. Evaluation of post–harvest handling methods for transcontinental truck shipments of cut carnations, chrysanthemums, and roses. Journal of the American Society for Horticultural Science, 1978, 103, 151–155
172 Farnham D S, Byrne T, Marousky F J, et al. Comparison of conditioning, precooling, transit method, and use of a floral preservative on cut flower quality. Journal of theAmerican Society for Horticultural Science, 1996, 104(4), 83–90
173 Anon. Vacuum cooling for fruits and vegetables. Food Processing Industry, 1981, 50(601), 24
174 Nunes M C N, Breacht J K, Morais A M, et al. Physical and chemical quality characteristics of strawberries after storage are reduced by a short delay to cooling. Postharvest Biology and Technology, 1995, 6(1–2), 17–28
175 Mitchell F G, Guillou R and Parsons R A. Manual no. 43: Commercial cooling of fruits and vegetables. Berkeley: University of California Press, 1972
176 Brash D. Carrots D postharvest handling for export. Levin Research Centre, The New Zealand Institute for Crop & Food Research Limited, Private Bag 4704, Christchurch, New Zealand, 1996
177 Thompson J, Cantwell M, Arpaia M L, et al. Effect of cooling delays on fruit and vegetable quality. Perishables Handling Quarterly Issue No. 105, 2001
178 Halevy A H and Mayak S. Senescence and postharvest physiology of cut flowers, Part
2. Horticultural Reviews, 1981, 3, 59–143
179 Brecheisen S, Haas H P and Rober R. Influence of water quality and chemical compounds on vase life of cut roses. Acta Horticulturae, 1995, 405, 392–400
180 van Meeteren U and van Gelder H. Effect of time since harvest and handling conditions on rehydration ability of cut chrysanthemum flowers. Postharvest Biology and Technology, 1999, 16, 185–193
181 Fjeld T and Str?mme E. Proceedings of the Sixth International Symposium on Postharvest Physiology of Ornamental Plants. Acta Horticulturae, 1995, 405, 434
182 Celikel F G. and Reid M S. Storage temperature affects the quality of cut flowers from the asteraceae. Horticultural Science, 2002, 37, 148-150
183廖立新,彭永宏,叶庆生.非洲菊鲜切花弯颈部位及有关原因.园艺学报, 2003, 30, 110–112
184苏军,叶文.扶郎花预处理及保鲜技术研究.福建热作科技, 1994, 19, 34–35
185 Burdett A N. The cause of bent neck in Cut Rose. Journal of the American Society for Horticultural Science, 1990, 95, 427–481
186 Tyree M T and Sperry J S. Vulnerability of xylem to cavitation and embolism. Annual Review of Plant Physiology and Plant Molecular Biology, 1989, 40, 19–38
187 Liang J and Zhang J. Collection of xylem sap at flow rate similar to in vivo transpiration flux. Plant and Cell Physiology, 1997, 38, 1375–1381
188 Zimmermann M H. Hydraulic architecture of some diffuse-porous trees. Canadian Journal of Botany, 1978, 56, 2286–2295
189 van Doorn W G. Water relations of cut flowers. Horticultural Reviews, 1997, 18, 81–85
190 Sperry J S, Donnelly J R and Tyree M T. A method for measuring hydraulic conductivity and embolism in xylem. Plant, Cell and Environment, 1988, 11, 35–40
191 Louband M, van Doorn W G. Wound-induced and bacteriainduced xylem blockage in rose, Astilbe, and Viburnum. Postharvest Biology and Technology, 2004, 32, 281–288
192马男,蔡蕾,陆旺金,等.外源乙烯对月季(Rosa hybrida)切花花朵开放的影响与乙烯生物合成相关基因表达的关联.中国科学(C辑), 2005, 35(2), 104–114
193 Desmond E, Kenny T and Ward P. The effect of injection level and cooling method on the quality of cooked ham joints. Meat Science, 2002, 60, 271–277
194李云飞,殷涌光,徐树来,等.食品物性学.北京:中国轻工业出版社, 2010
195 DeBelie N. Use of physico-chemical methods for assessment of sensory changes in carrot texture and sweetness during cooking. Journal of Texture Studies, 2002, 33, 367–388
196 Vanstreels E, Alamar M C, Verlinden B E, et al. Micromechanical behaviour of onion epidermal tissue. Postharvest Biology and Technology, 2005, 37, 163–173
197 Yu L D, Phanchaisri B, Apavatjrut P, et al. Some investigations of ion boPadment effects on plant cell wall surfaces. Surface and Coatings Technology, 2002, 158–159, 146–150
198 ASTM. Standard test method for tensile properties of thin plastic sheeting. Designation: D882–00. In: Annual book of ASTM standards (pp. 160–168). Philadelphia, PA: ASTM, 2000
199 Deng Y, Wu Y and Li Y F. Effects of high O2 levels on post–harvest quality and shelf life of table grapes during long–term storage. European Food Research and Technology, 2005, 221, 392–397
200汤顺青.色度学.北京:北京理工大学出版社, 1990
201 Mayor L, Pissarra J and Sereno A M. Microstructure changes during osmotic dehydration of parenchymatic pumpkin tissue. Journal of Food Engineering, 2008, 85, 326–339
202 Ramos I N, Silva C L M, Sereno A M, et al. Quantification of microstructural changes during first stage air drying of grape tissue. Journal of Food Engineering, 2004, 62, 159–164
203 Lewicki P P and Porzecka-Pawlak R. Effect of osmotic dewatering on apple tissue structure. Journal of Food Engineering, 2005, 66, 43–50
204 Jenkins L M and Donald A M. Use of the environmental scanning electron microscope for the observation of the swelling behaviour of cellulosic fibres. Scanning, 1996, 19, 92–97
205 Loodts J, Tijskens E, Wei C, et al. Micromechanics: Simulating the elastic behavior of onion epidermis tissue. Journal of Texture Studies, 2005, 37, 16–34
206 Hepworth D G and Bruce D M. Measuring the deformation of cells within a piece of compressed potato tuber tissue. Annales Botanici Fennici, 2000, 86, 287–292
207 Ha M A, Apperley D C and Jarvis M C. Molecular Rigidity in Dry and Hydrated Onion Cell Walls. Plant Physiology, 1997, 115, 593–598
208 Ng A, Parker ML, Parr AJ, et al. Physicochemical characteristics of onion (Allium cepa L.) tissues. Journal of Agricultural and Food Chemistry, 2000, 48, 5612–5617