脉冲强磁场对牛奶中微生物和酶的作用研究
摘要
牛奶中营养成分齐全,易消化吸收,被公认为是一种比较理想的天然食品。鲜牛奶中含有细菌、霉菌、酵母等多种微生物以及乳过氧化物酶、过氧化氢酶、脂肪酶、蛋白酶等多种酶类,而微生物和酶是导致食品腐败的重要因素。传统的加热杀菌方法能够有效杀灭牛奶中的微生物和钝化酶的活性,但容易造成营养成分的丧失,并引起牛奶感官品质的下降。脉冲强磁场作为一种新型的非热杀菌方法,有着传统热杀菌方法不可比拟的优势。本文研究脉冲强磁场对牛奶中微生物和酶的作用,并对脉冲强磁场杀菌钝酶的机理进行初步探讨。
本论文研究的主要内容和结果如下:
1.采用8T以上的脉冲强磁场对牛奶进行杀菌处理后,牛奶中菌落总数、大肠菌群、酵母和霉菌的存活率显著下降,且随着磁场强度和脉冲数增大,牛奶中微生物的存活率总体呈下降趋势,但存在有波动性变化。不同类型的微生物对脉冲磁场表现出不同的敏感性,大肠杆菌对脉冲磁场最为敏感,而酵母和霉菌对脉冲磁场有较强的抵抗力。
2.脉冲强磁场对牛奶中乳过氧化物酶、脂肪酶、过氧化氢酶有显著的钝化作用,并且对这三种酶的钝化作用均随着磁场强度的增大,脉冲数的增多而增强,并且脉冲强磁场对不同的酶作用不同,牛奶中的过氧化氢酶的活性最容易被钝化,而乳过氧化物酶则最难被钝化。
3.对脉冲强磁场处理前后牛奶的感官品质、营养成分、理化性质进行测定,发现脉冲强磁场处理方式不影响牛奶的感官品质,基本不会导致牛奶中营养成分的丧失,几乎不影响牛奶的理化性质。
4.通过对脉冲强磁场处理前后微生物进行扫描电镜和荧光显微镜观察,发现脉冲强磁场对微生物的作用位点在细胞膜上。脉冲强磁场导致微生物细胞的死亡,是由细胞膜受到破坏,通透性增大,引起细胞内原生质流失共同造成的。
5.通过对脉冲磁场处理前后的乳过氧化物酶和牛奶粗酶液的荧光光谱图以及圆二色谱图综合分析,可以推断乳过氧化物酶活性的变化主要是由二级结构的破坏引起的,而牛奶中其它酶类二级结构和三级结构的变化有待于进一步的研究。
Milk is recognized as an ideal natural food, because the nutrients in milk are complete, and easy to be digested and absorbed. Fresh milk contains various microorganisms, including bacteria, mold, and yeast, and also different kinds of enzymes, such as lactoperoxidase, catalase, lipase, protease and etc. Microbes and enzymes are the main reasons resulting in food corruption. Traditional thermal sterilization methods can kill microorganisms, and inactivate the enzymes in milk, but it is likely to cause loss of nutrients and decline in sensory quality of milk. As a new non-thermal sterilization method, pulsed magnetic field treatment has incomparable advantages than traditional thermal treatment. The effect of pulsed magnetic field on the microbes and enzymes in milk was studied in this paer. Then, the mechanisms of sterilization for microorganisms and inactive to enzymes were also investigated.
The main results of this thesis are as follows:
1. After treated by pulsed magnetic field with over 8T, the survival rate of total plate count, coliform, mold and yeast decreased significantly with the magnetic field intensity, and pulse number increasing, but existed fluctuations. Different types of microorganisms showed different sensitivity to pulsed magnetic field. The E. coli was the most sensitive to pulsed magnetic field, while the yeast and mold had strong resistance.
2. Pulsed magnetic field was remarkablely capable of inactivation to lactoperoxidase, lipase and catalase in milk, and the inactivation rised with increasese of the magnetic field intensity and the pulse number. Pulsed magnetic field had different impacts on various enzymes. Catalase was the most easy to be inactivated, while lactoperoxidase was the most difficult to be inactivated.
3. The sensory quality, nutrition, physical and chemical properties of milk before and after pulsed magnetic field treatment were investigated. These results showed that the pulsed magnetic field treatment hardly affected the sensory quality of milk, did not cause the loss of nutrients, and had no adverse effects on physical and chemical properties of milk.
4. The microorganisms treated by pulsed magnetic field were observed by scanning electron microscopy and fluorescence microscopy. It was indicated that the impacting location of pulsed magnetic field on the microorganisms was the cell membrane. The death of microbial cell lead by pulsed magnetic field was mainly caused by the destruction of the cell membrane and the loss of intracellular protoplasm.
5. With analyzing the Fluorescence spectra and the circular dichroism spectra, it can be concluded that the inactivation of lactoperoxidase was mainly caused by the destruction of secondary structure, while changes of secondary and tertiary structure about other enzymes in milk needs to be further investigated.
本论文研究的主要内容和结果如下:
1.采用8T以上的脉冲强磁场对牛奶进行杀菌处理后,牛奶中菌落总数、大肠菌群、酵母和霉菌的存活率显著下降,且随着磁场强度和脉冲数增大,牛奶中微生物的存活率总体呈下降趋势,但存在有波动性变化。不同类型的微生物对脉冲磁场表现出不同的敏感性,大肠杆菌对脉冲磁场最为敏感,而酵母和霉菌对脉冲磁场有较强的抵抗力。
2.脉冲强磁场对牛奶中乳过氧化物酶、脂肪酶、过氧化氢酶有显著的钝化作用,并且对这三种酶的钝化作用均随着磁场强度的增大,脉冲数的增多而增强,并且脉冲强磁场对不同的酶作用不同,牛奶中的过氧化氢酶的活性最容易被钝化,而乳过氧化物酶则最难被钝化。
3.对脉冲强磁场处理前后牛奶的感官品质、营养成分、理化性质进行测定,发现脉冲强磁场处理方式不影响牛奶的感官品质,基本不会导致牛奶中营养成分的丧失,几乎不影响牛奶的理化性质。
4.通过对脉冲强磁场处理前后微生物进行扫描电镜和荧光显微镜观察,发现脉冲强磁场对微生物的作用位点在细胞膜上。脉冲强磁场导致微生物细胞的死亡,是由细胞膜受到破坏,通透性增大,引起细胞内原生质流失共同造成的。
5.通过对脉冲磁场处理前后的乳过氧化物酶和牛奶粗酶液的荧光光谱图以及圆二色谱图综合分析,可以推断乳过氧化物酶活性的变化主要是由二级结构的破坏引起的,而牛奶中其它酶类二级结构和三级结构的变化有待于进一步的研究。
Milk is recognized as an ideal natural food, because the nutrients in milk are complete, and easy to be digested and absorbed. Fresh milk contains various microorganisms, including bacteria, mold, and yeast, and also different kinds of enzymes, such as lactoperoxidase, catalase, lipase, protease and etc. Microbes and enzymes are the main reasons resulting in food corruption. Traditional thermal sterilization methods can kill microorganisms, and inactivate the enzymes in milk, but it is likely to cause loss of nutrients and decline in sensory quality of milk. As a new non-thermal sterilization method, pulsed magnetic field treatment has incomparable advantages than traditional thermal treatment. The effect of pulsed magnetic field on the microbes and enzymes in milk was studied in this paer. Then, the mechanisms of sterilization for microorganisms and inactive to enzymes were also investigated.
The main results of this thesis are as follows:
1. After treated by pulsed magnetic field with over 8T, the survival rate of total plate count, coliform, mold and yeast decreased significantly with the magnetic field intensity, and pulse number increasing, but existed fluctuations. Different types of microorganisms showed different sensitivity to pulsed magnetic field. The E. coli was the most sensitive to pulsed magnetic field, while the yeast and mold had strong resistance.
2. Pulsed magnetic field was remarkablely capable of inactivation to lactoperoxidase, lipase and catalase in milk, and the inactivation rised with increasese of the magnetic field intensity and the pulse number. Pulsed magnetic field had different impacts on various enzymes. Catalase was the most easy to be inactivated, while lactoperoxidase was the most difficult to be inactivated.
3. The sensory quality, nutrition, physical and chemical properties of milk before and after pulsed magnetic field treatment were investigated. These results showed that the pulsed magnetic field treatment hardly affected the sensory quality of milk, did not cause the loss of nutrients, and had no adverse effects on physical and chemical properties of milk.
4. The microorganisms treated by pulsed magnetic field were observed by scanning electron microscopy and fluorescence microscopy. It was indicated that the impacting location of pulsed magnetic field on the microorganisms was the cell membrane. The death of microbial cell lead by pulsed magnetic field was mainly caused by the destruction of the cell membrane and the loss of intracellular protoplasm.
5. With analyzing the Fluorescence spectra and the circular dichroism spectra, it can be concluded that the inactivation of lactoperoxidase was mainly caused by the destruction of secondary structure, while changes of secondary and tertiary structure about other enzymes in milk needs to be further investigated.
引文
[1]韩刚.浅谈牛奶的营养价值[J].中国奶牛,1997,(3):46-48
[2]宋昆冈.乳(奶)的营养价值及其制品[J].中国食品工业,1998,(10):18-29
[3]陈秀明.牛奶是接近理想的食品[J].广西畜牧兽医,2000,16(3):11-13
[4]王惠霞,张丽.乳类产品营养价值浅析[J].中国乳业,2002,(12):23-24
[5]赵新淮,于国萍,张永忠等.乳品化学[M]. 2007:47-87
[6]郭本恒,吴昊,范陈剑等.乳品化学[M].北京:中国轻工业出版社,2001:131-438
[7]肖陆飞.牛奶与营养化学[J].安徽卫生职业技术学院学报,2004,3(3):91-92
[8] Haug A, Hostmark A T, Harstad O M. Bovine milk in human nutrition– a review[J]. Lipids in Health and Disease, 2007, 6(25): 1-16
[9]郭本恒,朱宏,吴正钧等.乳品微生物学[M].北京:中国轻工业出版社,2001:118-176
[10] Matta H, Punj V. Isolation and Identification of Lipolytic, Psychrotrophic Sporre Forming Bacteria from Raw milk[J]. International Journal of Dairy research, 1999, 52(2): 59-62
[11] Charteris W P, Kelly P M, Morelli L, et al. Ingredient Selection Criteria for Probiotic Microorganisms in functional dairy food[J]. International Journal of Dairy Technolgy, 1998, 51(4): 123-126
[12] Muir D D. The Shelf- life of Dairy Products: 1. Factors Influencing Raw Milk and Fresh Products[J]. Journal of the Society of Dairy Technology, 1996, 49(1): 24-32
[13] Fox P F, Kelly A L. Indigenous enzymes in milk: Overview and historical aspects—Part 1[J]. International Dairy Journal, 2006, (16): 500-516
[14]白木,周洁.乳中的酶类[J].开卷有益.求医问药,2004,(9):28-29
[15]王振阁,戚鑫,田玮.乳中的酶类、激素研究进展[J].河南畜牧兽医,2004,25(7):11-12
[16] Trujillo A J, Pozo P I, Guamis B. Effect of heat treatment on lactoperoxidase activity in caprine milk[J]. Small Ruminant Research, 2007, 67(23): 243–246
[17] Kelly A L, Fox P F. Indigenous enzymes in milk: A synopsis of future research requirements[J]. 2006, (16): 707-715
[18] Chen L, Daniel R M, Coolbear T. Detection and impact of protease and lipase activities in milk and milk powders[J]. International Dairy Journal, 2003, (13): 255-275
[19] Atmani D, Benboubetra M, Harrison R. Goat’s milk xanthine oxidoreductase is greatly deficient in molybdenum[J]. Journal of Dairy Research, 2004, (71): 7–13
[20] Fox P F, Kelly A L. Indigenous enzymes in milk: Overview and historical aspects—Part 2[J]. International Dairy Journal, 2006, (16): 517-532
[21]杨方琪、萧振金.食品杀菌技术[M].北京:中国食品出版社,1988,65-72
[22]曲春礼,张秀玲,李良.浅谈超高温灭菌奶与巴氏杀菌奶[J].乳品加工,2006,(5):61-63
[23]陆东林.谈谈巴氏杀菌奶和超高温灭菌奶[J].新疆畜牧业,2003,(4):11-11
[24]孔保华,张丽萍,李晓东等.乳品科学与技术[M].北京:科学出版社,2007:95-139
[25] Lin S J, Sun J, Cao D D, et al. Distinction of different heat-treated bovine milks by native-PAGE fingerprinting of their whey proteins[J]. Food Chemistry, 2010, 121(3): 803-808
[26] Chan E L, Kummer A, Losso J N, et al. Stability of bovine immunoglobulins to thermal treatment and processing [J]. Food Research International, 1995, 28(1): 9-16
[27] Christopher J. Bates, Ann Prentice. Breast milk as a source of vitamins, essential minerals and trace elements[J]. Pharmacology and Therapeutics, 1994, 62(12): 193-220
[28] Ljutovac K R, Park Y W, Gaucheron F, et al. Heat stability and enzymatic modifications of goat and sheep milk[J]. Small Ruminant Research, 2007, 68(12): 207-220
[29] Gliguem H, Birlouez-Aragon I. Effects of Sterilization, Packaging, and Storage on Vitamin C Degradation, Protein Denaturation, and Glycation in Fortified Milks[J]. Journal of Dairy Science, 2005, 88(3): 891-899
[30]廖小军,胡小松,张燕等.我国食品非热加工技术研究现状分析[A].潘蓓蕾. 2008中国食品工业与科技发展报告.北京:中国轻工业出版社,2008:77-88.
[31] De la Fuente-blanco S, Riera-franco de Sarabia E, Acosta-Aparicio V M, et al. Food drying process by power ultrasound[J]. Ultrasonics, 2006, 44(1): 523-527
[32]盖作启,李冰,李琳等.非热杀菌技术在牛奶加工中的研究进展[J]. 2009,30(1):329-332
[33]李汴生,阮征.非热杀菌技术与应用[M].北京:化学工业出版社,2004:155-176
[34] Schrive L, Grasmick A, Moussiere S, et al. Pulsed electric field treatment of Saccharomyces cerevisiae suspensions: A mechanistic approach coupling energy transfer, mass transfer and hydrodynamics[J]. Biochemical Engineering Journal, 2006, 27(3), 212–224
[35] Tauscher B. Pasteurization of food by hydrostatic high pressure: chemical aspects[J]. Zeitschrift für Lebensmitteluntersuchung und- Forschung A, 1995, 200(1): 3-13
[36] Matser A M, Krebbers B, van den Berg R W, et al. Advantages of high pressuresterilisation on quality of food products[J]. Trends in Food Science and Technology, 2004, 15(2): 79-85
[37] Smelt J P P M. Recent advances in the microbiology of high pressure processing[J]. Trends in Food Science and Technology, 1998, 9(4): 152-158
[38] Huhtanen C N. Effect of ultrasound on disaggregation of milk bacteria[J]. Journal of Dairy Science, 1966, 49(8): 1008-1010
[39] Mason T J, Paniwnyk L, Lorimer J P. The uses of ultrasound in food technology[J]. Ultrasonics Sonochemistry, 1996, 3(3): 253-260
[40]薛源,桂芬琦,孙志健等.高压CO2技术杀菌灭酶效果及其机理研究进展[J]. 2006,27(3):203-205
[41] Chen J S, Balaban M O, Wei C I, et al. Interaction of polyphenol oxidase by high pressure carbon dioxide[J]. Journal of Agricultural and Food Chemistry, 1992, 40(12): 2345-2349
[42] Enomoto A, Nakamura K, Hakoda M, et al. Lethal effect of high-pressure carbon dioxide on a bacterial spore[J] Journal of Fermentation and Bioengineering, 1997, 83(3): 305-307
[43] Erkmen O. Effect of carbon dioxide pressure on Listeria monocytogenes in physiological saline and foods[J]. Food Microbiology, 2000, 17(6): 589-596
[44] Hong S I, Pyun Y R. Membrane damage and enzyme inactivation of Lactobacillus plantarum by high pressure CO2 treatment[J]. Journal of Food Microbiology, 2001, 63: 19-28
[45]廖红梅,廖小军,胡小松等.影响DPCD技术杀菌效果的因素与杀菌机理分析[J].食品与发酵工业,2007,33(1):96-99
[46]杨巧绒,高梦祥,马海乐.强脉冲磁场的杀菌效果及对食品品质的影响[J].微波学报,2004,20(3):82-85
[47]殷红,葛长荣.食品冷杀菌技术[J].保鲜与加工,2005,5(1):40-41
[48] Akbas M Y, Ozdemir M. Effectiveness of ozone for inactivation of E. coli and B. cereus in pistachios[J].International Journal of Food Science and Technology, 2006, 41(5): 513-519
[49] Byun M, Yook H, Kang I, et al. Comparative effects of gamma irradiation and ozone treatment on hygienic quality of Korean red ginseng powder [J]. Radiation Physics and Chemistry, 1998,52(6): 95-99
[50] Dunn J, Ott T, Clark W. Pulsed light treatment of food and packaging[J]. FoodTechnologist, 1995, 49(9): 95-98
[51] Terajima T, Koinuma H. Development of a combinatorial atmospheric pressure cold plasma processor[J]. Applied Surface Science, 2004, 223(13): 259-263
[52] Chen J Y, Liao Y L, Wang T H, et al. Transformation of Escherichia coli mediated by magnetic nanoparticles in pulsed magnetic field[J]. Enzyme and Microbial Technology, 2006(39): 366-370
[53] Malko J A, Constantinidis I, Dillehay D, et al. Search for influence of 1.5 Tesla magnetic field on growth of yeast cells [J]. Bioelectromagnetics, 1994, (15): 495-501.
[54] San Martin M F, Harte F M, Lelieveld H, et al. Inactivation effect of an 18-T pulsed magnetic field combined with other technologies on Escherichia coli[J]. Innovative food science and emerging technologies, 2001,2: 273-277
[55] Okuno K, Tuchiya K, Ano T, et al. Effect of super high magnetic field on the growth of Escherichia coli under various medium compositions and temperatures[J]. Journal of Fermentation and Bioengineering, 1993, 75(2): 103-106
[56]邓玉林,马海乐,储金宇.食品电磁杀菌的原理及研究进展[J].食品工业,2002,(4):47-49
[57] Chizhov S V, Siniak I U E, Shikina M I, et al. Effect of a magnetic field on Escherichia coli [J] . Kosmicheskaia biologiia aviakosmicheskaia meditsina, 1975, 9(5):26-31.
[58] Moore R L. Biological effects of magnetic fields: studies with microorganisms[J]. Canadian Journal of Microbiology, 1979, 25(10):1145-1151
[59] Hofmann G A. Deactivation of microorganisms by an oscillating magnetic field[P]. US: Patent 4524079, 1985
[60]马海乐,邓玉林,储金宇.生啤酒的磁激发脉冲电磁场杀菌的试验研究[J].食品科学,2003,24(4):52-55
[61] Fojt L, Strasaka, Vetterl V, et al. Comparison of the low-frequency magnetic field effects on bacteria Escherichia coli, Leclercia adecarboxylata and Staphylococcus aureus[J]. Bioelectrochemistry, 2004, 63(12): 337-341
[62]高梦祥,马海乐,郭康权.西瓜汁的脉冲磁场杀菌试验[J].食品与发酵工业,2004,30(3):14-17
[63]高梦祥,马海乐,郭康权.脉冲磁场杀菌在牛奶杀菌中的应用研究[J].食品工业科技,2004,25(7):76-78
[64]王丽敏.苹果中微生物的分离鉴定及脉冲强磁场对苹果汁中腐败菌的影响[D].北京:中国农业大学,2004
[65] Ma H L, Pan Z L, Gao M X, et al. Efficacy in microbial sterilization of pulsed magnetic field treatment[J]. International Journal of Food Engineering, 2008, 4(4): 1-14
[66] Haberditzl W. Enzyme activity in high magnetic fields[J]. Nature, 1967, (213): 72–73
[67]刘勇.磁场对酶及酶促反应过程的影响[D].天津:天津大学,2007
[68] Portaccio M, De Luca P, Duranle D, et al. In virtro studies of the influence of ELF electromagnetic fields on the activity of soluble and insoluble peroxidase[J]. Bioelectromagntics, 2003, 24(7): 449-456
[69] Portaccio M, De Luca P, Duranle D, et al. Modulation of the catalytic activity of free and immobilized peroxidase by extremely low frequency electromagnetic fields: dependence on frequency[J].Bioelectromagnetics, 2005,26(2):145-152
[70] Blank M, Soo L. Effects of low frequency magnetic fields on Na, K-ATPase activity[J]. Bioelectrochemistry and Bioenergetics, 1995, 38(2): 267-273
[71] Blank M, Soo L. Frequency dependence of Na, K-ATPase function in magnetic fields[J]. Bioelectrochemistry and Bioenergetics, 1997, 42(2): 231-234
[72] Blank M, Soo L. Optimal frequencies for magnetic acceleration of cytochrome oxidase and Na, K-ATPase reactions[J].Bioelectrochemistry, 2001, 53(2): 171-174
[73] Farrell J M, Barber M, Krause D, et al. Effects of low frequency electromagnetic fields on the activity of ornithine decarboxylase in developing chicken embryos[J]. Bioelectrochemistry and Bioenergetics, 1997, 43(1): 91-96
[74] Ravera S, Repaci E, Morelli A, et al. Effects of extremely low frequency electromagnetic fields on the adenylate kinase activity of rod outer segment of bovine retina[J]. Bioelectromagnetics, 2004, 25(7): 545-551
[75]朱春梅,马海乐,任瑞.高强度脉冲磁场对辣根过氧化物酶活性的影响[J].安徽农业大学学报,2009,36(1):116-119
[76]金江涛,郑必胜,肖凯军.强脉冲磁场对草莓过氧化物酶活性的影响[J].现代食品科技,2009,125(10):1156-1158
[77] Mertens B., Knorr D., Developments of nonthermal processes for food preservation [J]. Food Technology, 1992, 46(5):124-133
[78] Cain C A. A theoretical basis for microwave and RF field effects on excitable cellular membranes[J]. IEEE transactions on microwave theory and techniques, 1980, 28(2): 142-147
[79] Galvanovskis J, Sandblom J. Periodic forcing of intracellular calcium oscillators.Theoretical studies of the effects of low-frequency fields on the magnitude of oscillations[J]. Bioelectrochemistry and Bioenergetics, 1998, 46(2): 161–174
[80]张小云.磁场对细胞生长分裂的影响及其机制的探讨[J].中国科学B辑,1989(,2): 164-170
[81]张小云.磁场的细胞效应研究[J].基础医学与临床,1994,14(5):15-19
[82]马海乐,邓玉林,储金宇.西瓜汁的高强度脉冲磁场杀菌试验研究及杀菌机理分析[J].农业工程学报,2003,19(2):163-166
[83]马海乐,吴琼英,高梦祥等.微生物不同生长期及介质参数对脉冲磁场杀菌效果的影响[J].农业工程学报,2004,20(5):215-217
[84]李江,胡道道.磁场对大分子构象的影响研究进展[J].高分子通报,2005,5(10):108-113
[85]王山衫,李琳,李冰.磁场对酶学效应影响的研究进展[J].现代生物医学进展,2006,6(11):111-114
[86]贺华君,朱元保,钟科军等.磁场对纤维素酶的活性及构象的影响[J].吉首大学学报(自然科学版),1998,19(1):41-46
[87]李红,胡道道,房喻等.磁场对大分子构象的影响研究进展[J].高分子通报,2005,5:108-113
[88]郑必胜,郭祀远,李琳等.磁场处理强化水溶液蒸发效能的研究[J].华南理工大学学报(自然科学版),1995,23(7):20-25
[89]许喜林,李琳,郭祀远等.静态磁场对细菌存活率的影响[J].微生物学通报,2005,32(5):1-4
[90]马森.牛乳中超氧化物歧化酶和过氧化氢酶测定及热稳定性研究[J].乳业科学与技术,2006,(1):7-8
[91]李冰,李洲仕,盖作启等.热-超声联合作用对牛奶品质的影响[J].食品科学,2009,30(19):78-80
[92]张勇,段旭昌,白燕红等.超高压杀菌处理对牛乳感官和理化特性的影响[J].中国乳品工业,2007,35(6):13-16
[93]王越男.高压处理对牛乳的物化性质和乳清蛋白变形情况的研究[D].呼和浩特:内蒙古农业大学,2004
[94]廖小军.高压脉冲电场系统设计及其杀菌灭酶效果与对苹果汁品质影响研究[D].北京:中国农业大学,2004
[95] Luo W, Zhang R B, Wang L M, et al. Conformation changes of Polyphenol Oxidase(PPO) and Lipoxygenase(LOX) induced by PEF Treatment[J]. Journal of applied electrochemistry, 2010, 40(2): 295-301
[96]尹寿伟,唐传核,温其标等.微射流处理对芸豆分离蛋白构象和功能特性的影响[J].华南理工大学学报(自然科学版),2009,37(10):112-116
[97]黄汉昌,姜招峰,朱宏吉.紫外圆二色光谱预测蛋白质结构的研究方法[J].化学通报,2007,(7):501-506
[98] Kelly S M, Price N C. The application of circular dichroism to studies of protein folding and unfolding[J]. Biochimca et biophysica acta, 1997, 1338: 161-185
[99] Yang J T, Wu C S, Martinez H M. Calculation of protein conformation from circular dichroism[J]. Methods in Enzymology, 1986, 130: 208-269
[100]沈琼,黄滨,邵嘉亮等.运用圆二色谱研究酶与化合物相互作用的机理[J].中山大学学报(自然科学版),2006,45(4):62-64
[101]沈星灿,梁宏,何锡文等.圆二色光谱分析蛋白质构象的方法及研究进展[J].分析化学,2004,32(3):388-394
[2]宋昆冈.乳(奶)的营养价值及其制品[J].中国食品工业,1998,(10):18-29
[3]陈秀明.牛奶是接近理想的食品[J].广西畜牧兽医,2000,16(3):11-13
[4]王惠霞,张丽.乳类产品营养价值浅析[J].中国乳业,2002,(12):23-24
[5]赵新淮,于国萍,张永忠等.乳品化学[M]. 2007:47-87
[6]郭本恒,吴昊,范陈剑等.乳品化学[M].北京:中国轻工业出版社,2001:131-438
[7]肖陆飞.牛奶与营养化学[J].安徽卫生职业技术学院学报,2004,3(3):91-92
[8] Haug A, Hostmark A T, Harstad O M. Bovine milk in human nutrition– a review[J]. Lipids in Health and Disease, 2007, 6(25): 1-16
[9]郭本恒,朱宏,吴正钧等.乳品微生物学[M].北京:中国轻工业出版社,2001:118-176
[10] Matta H, Punj V. Isolation and Identification of Lipolytic, Psychrotrophic Sporre Forming Bacteria from Raw milk[J]. International Journal of Dairy research, 1999, 52(2): 59-62
[11] Charteris W P, Kelly P M, Morelli L, et al. Ingredient Selection Criteria for Probiotic Microorganisms in functional dairy food[J]. International Journal of Dairy Technolgy, 1998, 51(4): 123-126
[12] Muir D D. The Shelf- life of Dairy Products: 1. Factors Influencing Raw Milk and Fresh Products[J]. Journal of the Society of Dairy Technology, 1996, 49(1): 24-32
[13] Fox P F, Kelly A L. Indigenous enzymes in milk: Overview and historical aspects—Part 1[J]. International Dairy Journal, 2006, (16): 500-516
[14]白木,周洁.乳中的酶类[J].开卷有益.求医问药,2004,(9):28-29
[15]王振阁,戚鑫,田玮.乳中的酶类、激素研究进展[J].河南畜牧兽医,2004,25(7):11-12
[16] Trujillo A J, Pozo P I, Guamis B. Effect of heat treatment on lactoperoxidase activity in caprine milk[J]. Small Ruminant Research, 2007, 67(23): 243–246
[17] Kelly A L, Fox P F. Indigenous enzymes in milk: A synopsis of future research requirements[J]. 2006, (16): 707-715
[18] Chen L, Daniel R M, Coolbear T. Detection and impact of protease and lipase activities in milk and milk powders[J]. International Dairy Journal, 2003, (13): 255-275
[19] Atmani D, Benboubetra M, Harrison R. Goat’s milk xanthine oxidoreductase is greatly deficient in molybdenum[J]. Journal of Dairy Research, 2004, (71): 7–13
[20] Fox P F, Kelly A L. Indigenous enzymes in milk: Overview and historical aspects—Part 2[J]. International Dairy Journal, 2006, (16): 517-532
[21]杨方琪、萧振金.食品杀菌技术[M].北京:中国食品出版社,1988,65-72
[22]曲春礼,张秀玲,李良.浅谈超高温灭菌奶与巴氏杀菌奶[J].乳品加工,2006,(5):61-63
[23]陆东林.谈谈巴氏杀菌奶和超高温灭菌奶[J].新疆畜牧业,2003,(4):11-11
[24]孔保华,张丽萍,李晓东等.乳品科学与技术[M].北京:科学出版社,2007:95-139
[25] Lin S J, Sun J, Cao D D, et al. Distinction of different heat-treated bovine milks by native-PAGE fingerprinting of their whey proteins[J]. Food Chemistry, 2010, 121(3): 803-808
[26] Chan E L, Kummer A, Losso J N, et al. Stability of bovine immunoglobulins to thermal treatment and processing [J]. Food Research International, 1995, 28(1): 9-16
[27] Christopher J. Bates, Ann Prentice. Breast milk as a source of vitamins, essential minerals and trace elements[J]. Pharmacology and Therapeutics, 1994, 62(12): 193-220
[28] Ljutovac K R, Park Y W, Gaucheron F, et al. Heat stability and enzymatic modifications of goat and sheep milk[J]. Small Ruminant Research, 2007, 68(12): 207-220
[29] Gliguem H, Birlouez-Aragon I. Effects of Sterilization, Packaging, and Storage on Vitamin C Degradation, Protein Denaturation, and Glycation in Fortified Milks[J]. Journal of Dairy Science, 2005, 88(3): 891-899
[30]廖小军,胡小松,张燕等.我国食品非热加工技术研究现状分析[A].潘蓓蕾. 2008中国食品工业与科技发展报告.北京:中国轻工业出版社,2008:77-88.
[31] De la Fuente-blanco S, Riera-franco de Sarabia E, Acosta-Aparicio V M, et al. Food drying process by power ultrasound[J]. Ultrasonics, 2006, 44(1): 523-527
[32]盖作启,李冰,李琳等.非热杀菌技术在牛奶加工中的研究进展[J]. 2009,30(1):329-332
[33]李汴生,阮征.非热杀菌技术与应用[M].北京:化学工业出版社,2004:155-176
[34] Schrive L, Grasmick A, Moussiere S, et al. Pulsed electric field treatment of Saccharomyces cerevisiae suspensions: A mechanistic approach coupling energy transfer, mass transfer and hydrodynamics[J]. Biochemical Engineering Journal, 2006, 27(3), 212–224
[35] Tauscher B. Pasteurization of food by hydrostatic high pressure: chemical aspects[J]. Zeitschrift für Lebensmitteluntersuchung und- Forschung A, 1995, 200(1): 3-13
[36] Matser A M, Krebbers B, van den Berg R W, et al. Advantages of high pressuresterilisation on quality of food products[J]. Trends in Food Science and Technology, 2004, 15(2): 79-85
[37] Smelt J P P M. Recent advances in the microbiology of high pressure processing[J]. Trends in Food Science and Technology, 1998, 9(4): 152-158
[38] Huhtanen C N. Effect of ultrasound on disaggregation of milk bacteria[J]. Journal of Dairy Science, 1966, 49(8): 1008-1010
[39] Mason T J, Paniwnyk L, Lorimer J P. The uses of ultrasound in food technology[J]. Ultrasonics Sonochemistry, 1996, 3(3): 253-260
[40]薛源,桂芬琦,孙志健等.高压CO2技术杀菌灭酶效果及其机理研究进展[J]. 2006,27(3):203-205
[41] Chen J S, Balaban M O, Wei C I, et al. Interaction of polyphenol oxidase by high pressure carbon dioxide[J]. Journal of Agricultural and Food Chemistry, 1992, 40(12): 2345-2349
[42] Enomoto A, Nakamura K, Hakoda M, et al. Lethal effect of high-pressure carbon dioxide on a bacterial spore[J] Journal of Fermentation and Bioengineering, 1997, 83(3): 305-307
[43] Erkmen O. Effect of carbon dioxide pressure on Listeria monocytogenes in physiological saline and foods[J]. Food Microbiology, 2000, 17(6): 589-596
[44] Hong S I, Pyun Y R. Membrane damage and enzyme inactivation of Lactobacillus plantarum by high pressure CO2 treatment[J]. Journal of Food Microbiology, 2001, 63: 19-28
[45]廖红梅,廖小军,胡小松等.影响DPCD技术杀菌效果的因素与杀菌机理分析[J].食品与发酵工业,2007,33(1):96-99
[46]杨巧绒,高梦祥,马海乐.强脉冲磁场的杀菌效果及对食品品质的影响[J].微波学报,2004,20(3):82-85
[47]殷红,葛长荣.食品冷杀菌技术[J].保鲜与加工,2005,5(1):40-41
[48] Akbas M Y, Ozdemir M. Effectiveness of ozone for inactivation of E. coli and B. cereus in pistachios[J].International Journal of Food Science and Technology, 2006, 41(5): 513-519
[49] Byun M, Yook H, Kang I, et al. Comparative effects of gamma irradiation and ozone treatment on hygienic quality of Korean red ginseng powder [J]. Radiation Physics and Chemistry, 1998,52(6): 95-99
[50] Dunn J, Ott T, Clark W. Pulsed light treatment of food and packaging[J]. FoodTechnologist, 1995, 49(9): 95-98
[51] Terajima T, Koinuma H. Development of a combinatorial atmospheric pressure cold plasma processor[J]. Applied Surface Science, 2004, 223(13): 259-263
[52] Chen J Y, Liao Y L, Wang T H, et al. Transformation of Escherichia coli mediated by magnetic nanoparticles in pulsed magnetic field[J]. Enzyme and Microbial Technology, 2006(39): 366-370
[53] Malko J A, Constantinidis I, Dillehay D, et al. Search for influence of 1.5 Tesla magnetic field on growth of yeast cells [J]. Bioelectromagnetics, 1994, (15): 495-501.
[54] San Martin M F, Harte F M, Lelieveld H, et al. Inactivation effect of an 18-T pulsed magnetic field combined with other technologies on Escherichia coli[J]. Innovative food science and emerging technologies, 2001,2: 273-277
[55] Okuno K, Tuchiya K, Ano T, et al. Effect of super high magnetic field on the growth of Escherichia coli under various medium compositions and temperatures[J]. Journal of Fermentation and Bioengineering, 1993, 75(2): 103-106
[56]邓玉林,马海乐,储金宇.食品电磁杀菌的原理及研究进展[J].食品工业,2002,(4):47-49
[57] Chizhov S V, Siniak I U E, Shikina M I, et al. Effect of a magnetic field on Escherichia coli [J] . Kosmicheskaia biologiia aviakosmicheskaia meditsina, 1975, 9(5):26-31.
[58] Moore R L. Biological effects of magnetic fields: studies with microorganisms[J]. Canadian Journal of Microbiology, 1979, 25(10):1145-1151
[59] Hofmann G A. Deactivation of microorganisms by an oscillating magnetic field[P]. US: Patent 4524079, 1985
[60]马海乐,邓玉林,储金宇.生啤酒的磁激发脉冲电磁场杀菌的试验研究[J].食品科学,2003,24(4):52-55
[61] Fojt L, Strasaka, Vetterl V, et al. Comparison of the low-frequency magnetic field effects on bacteria Escherichia coli, Leclercia adecarboxylata and Staphylococcus aureus[J]. Bioelectrochemistry, 2004, 63(12): 337-341
[62]高梦祥,马海乐,郭康权.西瓜汁的脉冲磁场杀菌试验[J].食品与发酵工业,2004,30(3):14-17
[63]高梦祥,马海乐,郭康权.脉冲磁场杀菌在牛奶杀菌中的应用研究[J].食品工业科技,2004,25(7):76-78
[64]王丽敏.苹果中微生物的分离鉴定及脉冲强磁场对苹果汁中腐败菌的影响[D].北京:中国农业大学,2004
[65] Ma H L, Pan Z L, Gao M X, et al. Efficacy in microbial sterilization of pulsed magnetic field treatment[J]. International Journal of Food Engineering, 2008, 4(4): 1-14
[66] Haberditzl W. Enzyme activity in high magnetic fields[J]. Nature, 1967, (213): 72–73
[67]刘勇.磁场对酶及酶促反应过程的影响[D].天津:天津大学,2007
[68] Portaccio M, De Luca P, Duranle D, et al. In virtro studies of the influence of ELF electromagnetic fields on the activity of soluble and insoluble peroxidase[J]. Bioelectromagntics, 2003, 24(7): 449-456
[69] Portaccio M, De Luca P, Duranle D, et al. Modulation of the catalytic activity of free and immobilized peroxidase by extremely low frequency electromagnetic fields: dependence on frequency[J].Bioelectromagnetics, 2005,26(2):145-152
[70] Blank M, Soo L. Effects of low frequency magnetic fields on Na, K-ATPase activity[J]. Bioelectrochemistry and Bioenergetics, 1995, 38(2): 267-273
[71] Blank M, Soo L. Frequency dependence of Na, K-ATPase function in magnetic fields[J]. Bioelectrochemistry and Bioenergetics, 1997, 42(2): 231-234
[72] Blank M, Soo L. Optimal frequencies for magnetic acceleration of cytochrome oxidase and Na, K-ATPase reactions[J].Bioelectrochemistry, 2001, 53(2): 171-174
[73] Farrell J M, Barber M, Krause D, et al. Effects of low frequency electromagnetic fields on the activity of ornithine decarboxylase in developing chicken embryos[J]. Bioelectrochemistry and Bioenergetics, 1997, 43(1): 91-96
[74] Ravera S, Repaci E, Morelli A, et al. Effects of extremely low frequency electromagnetic fields on the adenylate kinase activity of rod outer segment of bovine retina[J]. Bioelectromagnetics, 2004, 25(7): 545-551
[75]朱春梅,马海乐,任瑞.高强度脉冲磁场对辣根过氧化物酶活性的影响[J].安徽农业大学学报,2009,36(1):116-119
[76]金江涛,郑必胜,肖凯军.强脉冲磁场对草莓过氧化物酶活性的影响[J].现代食品科技,2009,125(10):1156-1158
[77] Mertens B., Knorr D., Developments of nonthermal processes for food preservation [J]. Food Technology, 1992, 46(5):124-133
[78] Cain C A. A theoretical basis for microwave and RF field effects on excitable cellular membranes[J]. IEEE transactions on microwave theory and techniques, 1980, 28(2): 142-147
[79] Galvanovskis J, Sandblom J. Periodic forcing of intracellular calcium oscillators.Theoretical studies of the effects of low-frequency fields on the magnitude of oscillations[J]. Bioelectrochemistry and Bioenergetics, 1998, 46(2): 161–174
[80]张小云.磁场对细胞生长分裂的影响及其机制的探讨[J].中国科学B辑,1989(,2): 164-170
[81]张小云.磁场的细胞效应研究[J].基础医学与临床,1994,14(5):15-19
[82]马海乐,邓玉林,储金宇.西瓜汁的高强度脉冲磁场杀菌试验研究及杀菌机理分析[J].农业工程学报,2003,19(2):163-166
[83]马海乐,吴琼英,高梦祥等.微生物不同生长期及介质参数对脉冲磁场杀菌效果的影响[J].农业工程学报,2004,20(5):215-217
[84]李江,胡道道.磁场对大分子构象的影响研究进展[J].高分子通报,2005,5(10):108-113
[85]王山衫,李琳,李冰.磁场对酶学效应影响的研究进展[J].现代生物医学进展,2006,6(11):111-114
[86]贺华君,朱元保,钟科军等.磁场对纤维素酶的活性及构象的影响[J].吉首大学学报(自然科学版),1998,19(1):41-46
[87]李红,胡道道,房喻等.磁场对大分子构象的影响研究进展[J].高分子通报,2005,5:108-113
[88]郑必胜,郭祀远,李琳等.磁场处理强化水溶液蒸发效能的研究[J].华南理工大学学报(自然科学版),1995,23(7):20-25
[89]许喜林,李琳,郭祀远等.静态磁场对细菌存活率的影响[J].微生物学通报,2005,32(5):1-4
[90]马森.牛乳中超氧化物歧化酶和过氧化氢酶测定及热稳定性研究[J].乳业科学与技术,2006,(1):7-8
[91]李冰,李洲仕,盖作启等.热-超声联合作用对牛奶品质的影响[J].食品科学,2009,30(19):78-80
[92]张勇,段旭昌,白燕红等.超高压杀菌处理对牛乳感官和理化特性的影响[J].中国乳品工业,2007,35(6):13-16
[93]王越男.高压处理对牛乳的物化性质和乳清蛋白变形情况的研究[D].呼和浩特:内蒙古农业大学,2004
[94]廖小军.高压脉冲电场系统设计及其杀菌灭酶效果与对苹果汁品质影响研究[D].北京:中国农业大学,2004
[95] Luo W, Zhang R B, Wang L M, et al. Conformation changes of Polyphenol Oxidase(PPO) and Lipoxygenase(LOX) induced by PEF Treatment[J]. Journal of applied electrochemistry, 2010, 40(2): 295-301
[96]尹寿伟,唐传核,温其标等.微射流处理对芸豆分离蛋白构象和功能特性的影响[J].华南理工大学学报(自然科学版),2009,37(10):112-116
[97]黄汉昌,姜招峰,朱宏吉.紫外圆二色光谱预测蛋白质结构的研究方法[J].化学通报,2007,(7):501-506
[98] Kelly S M, Price N C. The application of circular dichroism to studies of protein folding and unfolding[J]. Biochimca et biophysica acta, 1997, 1338: 161-185
[99] Yang J T, Wu C S, Martinez H M. Calculation of protein conformation from circular dichroism[J]. Methods in Enzymology, 1986, 130: 208-269
[100]沈琼,黄滨,邵嘉亮等.运用圆二色谱研究酶与化合物相互作用的机理[J].中山大学学报(自然科学版),2006,45(4):62-64
[101]沈星灿,梁宏,何锡文等.圆二色光谱分析蛋白质构象的方法及研究进展[J].分析化学,2004,32(3):388-394