乙二醇蓄冷库性能及其在黄冠梨保鲜上的应用
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摘要
为解决果蔬贮藏保鲜设施运行成本高的问题,促进产地冷藏设施建设,研制了以乙二醇为载冷剂的蓄冷库,并对该库的性能、贮藏保鲜效果和运行成本进行了分析,探讨该冷库用于果品贮藏保鲜的可能性。研究发现乙二醇蓄冷库的平均温度为0.18~0.32℃,测温点间最大温差为0.8℃,好于对照冷藏库。结果说明乙二醇蓄冷库的温度稳定性和均匀性较好,有利于保障果品贮藏品质。乙二醇蓄冷库和对照冷藏库用于贮藏黄冠梨,贮藏效果差异不大。一个贮藏周期一间容量30t的乙二醇蓄冷库,用电量略高于对照冷藏库;但因实行峰谷电价,运行电费仅是对照冷库的75%。总体来说,与对照冷藏库相比,研制的乙二醇蓄冷库性能优良,保鲜效果理想,运行成本更低,是实施峰谷电价地区适宜的果品贮藏保鲜设施。
The cold storage facility exhibited features of energy wasting and higher running cost. In underdeveloped regions that became one of the most important reasons to backward construction of storage and preservation facility of fruit and vegetable. This problem was obstacle for sound development of storage and keeping-fresh industry of fruit and vegetable in China. In order to solve the problem above, and accelerate the construction of cold storage facility in site of production, it would build new energy-saving cold storage facility. The cold storage with ethylene glycol as secondary refrigerant was developed. The newly developed cold storage was composed of 3 circle systems, i.e. compressor refrigeration system, secondary refrigerant cycle system, and cold storage room refrigeration system. The phase-changed material was ethylene glycol, which was widely used in ice-storage air-condition. For exploring possibility of cold storage with ethylene glycol as secondary refrigerant for storage and preservation of fruit, performance, storage and preservation effects, and running cost of the new cold storage were analyzed. To detect performance, temperatures at different sites in the cold storage room and evaporator output draught were measured. Over the period of the experiments, average temperature at 5 test sites of the newly developed freezer is 0.18-0.32 ℃, while the same index of control cold storage is-0.10-1.00 ℃. The maximum temperature difference of the newly developed refrigerator among test sites is 0.8 ℃, less than 1.5 ℃ of control cold storage. Temperature fluctuation range of evaporator output draught of the newly developed cold storage is-0.8--0.2 ℃, less than that of control cold storage. All these results indicate that cold storage with ethylene glycol as secondary refrigerant shows preferable temperature stability and uniformity, which is useful to guarantee good storage quality of fruit. To analyze storage and preservation effects, both newly developed freezer and control cold storage were used to store Huangguan pear, and the postharvest quality was detected, such as weight loss, soluble solids content, rot rate, and brown heart rate. Weight loss and brown heart rate of Huangguan pear stored by the newly developed refrigerator are smaller than those by control cold storage, and there is no significant difference between cold storage with ethylene glycol as secondary refrigerant and control cold storage in storage effects of Huangguan pear. The power consumption of a cold storage with ethylene glycol as secondary refrigerant with 30 t capacity is about 7 523.12 kW×h, which is a little higher than that of control cold storage. Using peak and valley price, electricity bill of developed cold storage is only 75% of that of control cold storage. Overall, compared with control cold storage, the newly developed cold storage with ethylene glycol as secondary refrigerant shows good performance, satisfactory fresh-keeping effect, and lower running cost, which indicates this developed storage facility is suitable for storage and preservation of fruit in area using peak and valley price policy.
The cold storage facility exhibited features of energy wasting and higher running cost. In underdeveloped regions that became one of the most important reasons to backward construction of storage and preservation facility of fruit and vegetable. This problem was obstacle for sound development of storage and keeping-fresh industry of fruit and vegetable in China. In order to solve the problem above, and accelerate the construction of cold storage facility in site of production, it would build new energy-saving cold storage facility. The cold storage with ethylene glycol as secondary refrigerant was developed. The newly developed cold storage was composed of 3 circle systems, i.e. compressor refrigeration system, secondary refrigerant cycle system, and cold storage room refrigeration system. The phase-changed material was ethylene glycol, which was widely used in ice-storage air-condition. For exploring possibility of cold storage with ethylene glycol as secondary refrigerant for storage and preservation of fruit, performance, storage and preservation effects, and running cost of the new cold storage were analyzed. To detect performance, temperatures at different sites in the cold storage room and evaporator output draught were measured. Over the period of the experiments, average temperature at 5 test sites of the newly developed freezer is 0.18-0.32 ℃, while the same index of control cold storage is-0.10-1.00 ℃. The maximum temperature difference of the newly developed refrigerator among test sites is 0.8 ℃, less than 1.5 ℃ of control cold storage. Temperature fluctuation range of evaporator output draught of the newly developed cold storage is-0.8--0.2 ℃, less than that of control cold storage. All these results indicate that cold storage with ethylene glycol as secondary refrigerant shows preferable temperature stability and uniformity, which is useful to guarantee good storage quality of fruit. To analyze storage and preservation effects, both newly developed freezer and control cold storage were used to store Huangguan pear, and the postharvest quality was detected, such as weight loss, soluble solids content, rot rate, and brown heart rate. Weight loss and brown heart rate of Huangguan pear stored by the newly developed refrigerator are smaller than those by control cold storage, and there is no significant difference between cold storage with ethylene glycol as secondary refrigerant and control cold storage in storage effects of Huangguan pear. The power consumption of a cold storage with ethylene glycol as secondary refrigerant with 30 t capacity is about 7 523.12 kW×h, which is a little higher than that of control cold storage. Using peak and valley price, electricity bill of developed cold storage is only 75% of that of control cold storage. Overall, compared with control cold storage, the newly developed cold storage with ethylene glycol as secondary refrigerant shows good performance, satisfactory fresh-keeping effect, and lower running cost, which indicates this developed storage facility is suitable for storage and preservation of fruit in area using peak and valley price policy.
引文
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[17]修方珑,张岩,王世清,等.基于基于热管技术的储粮仓温度特征及其抑虫效果[J].农业工程学报,2013,29(14):256-261.Xiu Fanglong,Zhang Yan,Wang Shiqing,et al.Temperature characteristic and inhibition effect on insect pest in grain storehouse based on heat pipe technology[J].Transactions of the Chinese Society of Agricultural Engineering(Transactions of the CSAE),2013,29(14):256-261.(in Chinese with English abstract)
[18]应铁进,朱冰清,戚晓丽,等.用于农产品保鲜的有机物水溶液相变蓄冷剂[J].农业机械学报,2015,46(2):208-212,207.Ying Tiejin,Zhu Bingqing,Qi Xiaoli,et al.Development of organics solution phase change materials for preservation of agricultural products[J].Transactions of the Chinese Society for Agricultural Machinery,2015,46(2):208-212,207.(in Chinese with English abstract)
[19]丁庆,段绍辉,王执中,等.冰蓄冷空调在高峰谷负荷差地区应用的经济性[J].电力系统及其自动化学报,2014,26(1):72-75,80.Ding Qing,Duan Shaohui,Wang Zhizhong,et al.Economy of ice-storage air-condition used in the area of high peak-valley load difference[J].Proceedings of the CSU-EPSA,2014,26(1):72-75,80.(in Chinese with English abstract)
[20]Cao Jiankang,Zhao Yumei,Wang Meng,et al.Effects of1-methylcyclopropene on apricot fruit quality,decay,and on physiological and biochemical metabolism during shelf-life following long-term cold storage[J].Journal of Horticultural Science&Biotechnology,2009,84(6):672-676.
[21]Pan Hanxu,Wang Rui,Li Lili,et al.Manipulation of ripening progress of different plum cultivars during shelf life by post-storage treatments with ethylene and1-methylcyclopropene[J].Scientia Horticulturae,2016,198:176-182.
[22]Wang Jiao,Pan Hanxu,Wang Rui,et al.Patterns of flesh reddening,translucency,ethylene production and storability of‘Friar’plum fruit harvested at three maturity stages as affected by the storage temperature[J].Postharvest Biology and Technology,2016,121:9-18.
[23]Li Jian,Yan Jiaqi,Cao Jiankang,et al.Preventing the wound-induced deterioration of Yali pears by chitosan coating treatments[J].Food Science and Technology International,2012,18(2):123-128.
[24]张娜,李昆仑,王文生,等.应用臭氧浓度精准控制熏蒸装置提高树莓贮藏品质[J].农业工程学报,2017,33(10):295-301.Zhang Na,Li Kunlun,Wang Wensheng,et al.Application of ozone concentration precise control fumigation device improving quality of raspberries during cold storage[J].Transactions of the Chinese Society of Agricultural Engineering(Transactions of the CSAE),2017,33(10):295-301.(in Chinese with English abstract)
[25]陈天及,余克志.装配式冷库温度场特性的实验研究[J].制冷,2001,20(1):21-23.Chen Tianji,Yu Kezhi.The experimental study on the characteristics of temperature field inside a fabricated cold store[J].Refrigeration,2001,20(1):21-23.(in Chinese with English abstract)
[26]Tano K,OuléM K,Doyon G,et al.Comparative evaluation of the effect of storage temperature fluctuation on modified atmosphere packages of selected fruit and vegetables[J].Postharvest Biology and Technology,2007,46(3):212-221.
[27]Margeirsson B,Pálsson H,Gospavic R,et al.Numerical modelling of temperature fluctuations of chilled and superchilled cod fillets packaged in expanded polystyrene boxes stored on pallets under dynamic temperature conditions[J].Journal of food engineering,2012,113(1):87-99.
[28]刘佳,乔丽萍,李喜宏,等.温度波动对黄瓜贮藏冷害及品质影响[J].食品工业,2017,38(4):52-54.Liu Jia,Qiao Liping,Li Xihong,et al.Effect of temperature fluctuation on chilling injury and storage qualities of cucumber[J].The food industry,2017,38(4):52-54.(in Chinese with English abstract)
[29]王玲利,刘超,黄艳花,等.‘黄冠’梨采后热处理和钙处理对其钙形态及细胞壁物质代谢的影响[J].园艺学报,2014,41(2):249-258.Wang Lingli,Liu Chao,Huang Yanhua,et al.Effects of postharvest heat and calcium treatments on calcium fractions and cell wall metabolism of‘huangguan’pear fruit[J].Acta horticulturae sinica,2014,41(2):249-258.(in Chinese with English abstract)
[30]吴小华,颉敏华,王学喜,等.1-MCP对不同采收期黄冠梨褐心病及贮藏品质的影响[J].食品与机械,2016,32(1):110-113.Wu Xiaohua,Xie Minhua,Wang Xuexi,et al.Effects of1-MCP treatment on browning heart and storage quality of Huangguan pears with different harvest[J].Food&machinery,2016,32(1):110-113.(in Chinese with English abstract)
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[2]朱志强,张小栓,于晋泽.我国鲜活农产品冷链物流与纳米蓄冷材料的应用[J].中国果菜,2014,34(6):14-18.Zhu Zhiqiang,Zhang Xiaoshuan,Yu Jinze.Nano cool-storage material and cold-chain logistics of fresh agriculture products[J].China Fruit Vegetable,2014,34(6):14-18.(in Chinese with English abstract)
[3]黄雪莲,于新,马永全.蓄冷技术在果蔬保鲜中的研究与应用[J].仲恺农业技术学院学报,2010,23(2):67-71.Huang Xuelian,Yu Xin,Ma Yongquan.Study and application of cool storage technology in fruits and vegetables preservation[J].Journal of Zhongkai University of Agriculture and Engineering,2010,23(2):67-71.(in Chinese with English abstract)
[4]余华明.冷库及冷藏技术[M].北京:人民邮电出版社,2007.
[5]黄艳,章学来.蓄冷技术在食品冷链物流中的研究进展[J].包装工程,2015,36(15):23-29.Huang Yan,Zhang Xuelai.Research progress of the application of cold storage technology in food cold chain logistics[J].Packaging Engineering,2015,36(15):23-29.(in Chinese with English abstract)
[6]Rathod M K,Banerjee J.Thermal stability of phase change materials used in latent energy storage systems:A review[J].Renewable and Sustainable Energy Reviews,2013,18:246-258.
[7]周敏,杨春芳.蓄冷技术的应用及冰蓄冷工程的优化设计[J].电力需求侧管理,2013,15(5):1-5.Zhou Min,Yang Chunfang.The application of cool storage technology and optimal design of ice storage[J].Power Demand Side Management,2013,15(5):1-5.(in Chinese with English abstract)
[8]Sharma A,Tyagi V,Chen C R,et al.Review on thermal energy storage with phase change materials and applications[J].Renewable and Sustainable Energy Review,2009,13(2):318-345.
[9]Farid M M,Khudhair A M,Siddique A K,et al.A review on phase change energy storage:Materials and applications[J].Energy Conversion and Management,2004,45(9/10):1597-1615.
[10]Sarier N,Onder E.Organic phase change materials and their textile applications:An overview[J].Thermochimica Acta,2012,540(14):7-60.
[11]汪向磊,王文梅,曹和平,等.蓄冷技术现状及研究进展[J].山西化工,2016,36(1):34-40.Wang Xianglei,Wang Wenmei,Cao Heping,et al.Current status and recent advance of cold storage technology[J].Shanxi chemical industry,2016,36(1):34-40.(in Chinese with English abstract)
[12]王倩,王淑云.关于发展蓄冷式冷链物流多温共配的思考[J].中国海洋大学学报:社会科学版,2012(5):49-54.Wang Qian,Wang Shuyun.Reflections on the development of multi-temperature joint distribution based on storage cold chain logistics[J].Journal of Ocean University of China:Social Sciences,2012(5):49-54.(in Chinese with English abstract)
[13]Fu Xiaowei,Liu Zhimeng,Xiao Yao,et al.Preparation and properties of lauric acid/diatomite composites as novel form-stable phase change materials for thermal energy storage[J].Energy&Buildings,2015,104:244-249.
[14]刘金光,熊旭波,王世清,等.低温热管中无氟制冷剂HCR-22的蓄冷效果[J].农业工程学报,2016,32(19):268-273.Liu Jinguang,Xiong Xubo,Wang Shiqing,et al.Cooling effect of fluorine free refrigerant HCR-22 used in heat pipe[J].Transactions of the Chinese Society of Agricultural Engineering(Transactions of the CSAE),2016,32(19):268-273.(in Chinese with English abstract)
[15]应铁进,苏党,白家玮.用于用于非冷冻低温区运输的复合有机物相变蓄冷剂[J].农业机械学报,2017,48(8):309-314.Ying Tiejun,Su Dang,Bai Jiawei.Organic phase change compound materials for non-freezing cold chain[J].Transactions of The Chinese Society of Agricultural Machinery,2017,48(8):309-314.(in Chinese with English abstract)
[16]徐笑锋,章学来,Munyalo J M,等.十水硫酸钠相变蓄冷保温箱保冷特性的试验研究.农业工程学报,2017,33(22):308-314.Xu Xiaofeng,Zhang Xuelai,Munyalo J M,et al.Experimental study on cold retention characteristics of cold storage incubator using Na2SO4·10H2O as PCMs[J].Transactions of the Chinese Society of Agricultural Engineering(Transactions of the CSAE),2017,33(22):308-314.(in Chinese with English abstract)
[17]修方珑,张岩,王世清,等.基于基于热管技术的储粮仓温度特征及其抑虫效果[J].农业工程学报,2013,29(14):256-261.Xiu Fanglong,Zhang Yan,Wang Shiqing,et al.Temperature characteristic and inhibition effect on insect pest in grain storehouse based on heat pipe technology[J].Transactions of the Chinese Society of Agricultural Engineering(Transactions of the CSAE),2013,29(14):256-261.(in Chinese with English abstract)
[18]应铁进,朱冰清,戚晓丽,等.用于农产品保鲜的有机物水溶液相变蓄冷剂[J].农业机械学报,2015,46(2):208-212,207.Ying Tiejin,Zhu Bingqing,Qi Xiaoli,et al.Development of organics solution phase change materials for preservation of agricultural products[J].Transactions of the Chinese Society for Agricultural Machinery,2015,46(2):208-212,207.(in Chinese with English abstract)
[19]丁庆,段绍辉,王执中,等.冰蓄冷空调在高峰谷负荷差地区应用的经济性[J].电力系统及其自动化学报,2014,26(1):72-75,80.Ding Qing,Duan Shaohui,Wang Zhizhong,et al.Economy of ice-storage air-condition used in the area of high peak-valley load difference[J].Proceedings of the CSU-EPSA,2014,26(1):72-75,80.(in Chinese with English abstract)
[20]Cao Jiankang,Zhao Yumei,Wang Meng,et al.Effects of1-methylcyclopropene on apricot fruit quality,decay,and on physiological and biochemical metabolism during shelf-life following long-term cold storage[J].Journal of Horticultural Science&Biotechnology,2009,84(6):672-676.
[21]Pan Hanxu,Wang Rui,Li Lili,et al.Manipulation of ripening progress of different plum cultivars during shelf life by post-storage treatments with ethylene and1-methylcyclopropene[J].Scientia Horticulturae,2016,198:176-182.
[22]Wang Jiao,Pan Hanxu,Wang Rui,et al.Patterns of flesh reddening,translucency,ethylene production and storability of‘Friar’plum fruit harvested at three maturity stages as affected by the storage temperature[J].Postharvest Biology and Technology,2016,121:9-18.
[23]Li Jian,Yan Jiaqi,Cao Jiankang,et al.Preventing the wound-induced deterioration of Yali pears by chitosan coating treatments[J].Food Science and Technology International,2012,18(2):123-128.
[24]张娜,李昆仑,王文生,等.应用臭氧浓度精准控制熏蒸装置提高树莓贮藏品质[J].农业工程学报,2017,33(10):295-301.Zhang Na,Li Kunlun,Wang Wensheng,et al.Application of ozone concentration precise control fumigation device improving quality of raspberries during cold storage[J].Transactions of the Chinese Society of Agricultural Engineering(Transactions of the CSAE),2017,33(10):295-301.(in Chinese with English abstract)
[25]陈天及,余克志.装配式冷库温度场特性的实验研究[J].制冷,2001,20(1):21-23.Chen Tianji,Yu Kezhi.The experimental study on the characteristics of temperature field inside a fabricated cold store[J].Refrigeration,2001,20(1):21-23.(in Chinese with English abstract)
[26]Tano K,OuléM K,Doyon G,et al.Comparative evaluation of the effect of storage temperature fluctuation on modified atmosphere packages of selected fruit and vegetables[J].Postharvest Biology and Technology,2007,46(3):212-221.
[27]Margeirsson B,Pálsson H,Gospavic R,et al.Numerical modelling of temperature fluctuations of chilled and superchilled cod fillets packaged in expanded polystyrene boxes stored on pallets under dynamic temperature conditions[J].Journal of food engineering,2012,113(1):87-99.
[28]刘佳,乔丽萍,李喜宏,等.温度波动对黄瓜贮藏冷害及品质影响[J].食品工业,2017,38(4):52-54.Liu Jia,Qiao Liping,Li Xihong,et al.Effect of temperature fluctuation on chilling injury and storage qualities of cucumber[J].The food industry,2017,38(4):52-54.(in Chinese with English abstract)
[29]王玲利,刘超,黄艳花,等.‘黄冠’梨采后热处理和钙处理对其钙形态及细胞壁物质代谢的影响[J].园艺学报,2014,41(2):249-258.Wang Lingli,Liu Chao,Huang Yanhua,et al.Effects of postharvest heat and calcium treatments on calcium fractions and cell wall metabolism of‘huangguan’pear fruit[J].Acta horticulturae sinica,2014,41(2):249-258.(in Chinese with English abstract)
[30]吴小华,颉敏华,王学喜,等.1-MCP对不同采收期黄冠梨褐心病及贮藏品质的影响[J].食品与机械,2016,32(1):110-113.Wu Xiaohua,Xie Minhua,Wang Xuexi,et al.Effects of1-MCP treatment on browning heart and storage quality of Huangguan pears with different harvest[J].Food&machinery,2016,32(1):110-113.(in Chinese with English abstract)
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