山羊肉奶制品和鸡肉的质量与安全

论文摘要

本文对山羊肉电阻和各向异性现象进行了研究。试验变量为交流低电压10,20和30VAC和频率10-10KHz。所采用的电压波形分别为正弦、方形和锯齿方形形。在各种波形下,电压和频率的联合作用是非常明显的。实验结果表明,方形波时电阻最小,其次为正弦和锯齿形波。沿着肉纹方向的电阻明显比横跨肉纹方向低。将脉冲直流方波信号放大后应用于山羊肉的表面杀菌。将表面涂以大肠杆菌E.coli.0157:H7的样品放入0.15M的氯化钠溶液中。试验参数分别为:输入电流10,20和30mA;通电时:2,8和32分钟;不同频率100,1K和10KHz,和通电周期:30,50和80%。试验结果表明,通电32分钟,三种电流强度（10,20和30mA）均可有效的杀死大肠杆菌。最佳条件下可杀死高达8Log10（99.999999%）的大肠杆菌。SPR光学生物传感器对沙门氏菌具有很高的敏感性。将传统的SPR光学传感器置于系列抗体溶液中即转化为生物传感器。试验表明,SPR生物传感器可以快速（少于30分钟）检测浓度在107CFU/mL的沙门氏菌。因此在检测致病性细菌监测方面SPR生物传感器具有很大的应用潜力。本文采用先进的数显旋转黏度计测量山羊奶制品的黏度,对山羊全脂奶,2%脱脂奶,1%脱脂奶,脱脂乳和奶油的黏度进行了测量。测量了脱脂百分比,剪切率和温度对山羊奶和奶油的黏度影响。在温度>60℃时,山羊奶表现了牛顿流体现象。在温度<60℃时,山羊奶和奶油等所有山羊奶制品的黏度随剪切率按指数规律变化。山羊奶的脂肪含量高时,黏度也随之增高。本文还建立了山羊奶和奶油的流变类型等。随着温度的升高,呈现多项式的关系。但是,在所有的温度下,奶油的黏度随剪切率的变化呈不同的指数关系。另一方面,粘度随温度的升高而降低。所有类型的牛奶除脱脂乳,多项式的关系随着温度的升高呈线性下降趋势。山羊奶的粘度值随着脂肪含量的增加而增大。本文还建立了山羊奶和奶油的流变模型。

论文目录

• SUMMARY
• CHAPTER 1 INTRODUCTION
• 1.1 FOOD SAFETY FOR GOAT MEAT
• 1.2 BIOSENSOR
• 1.3 GOAT MILK
• CHAPTER 2 ELECTRICAL RESISTIVITY OF GOAT MEAT
• 2.1 INTRODUCTION
• 2.2 MATERIALS AND METHODS
• 2.3 RESULTS AND DISCUSSION
• 2.3.1 The Trends of Output Voltage and Current through Meat Samples
• 2.3.2 Effect of Input voltage, Frequency and Waveform on the Resistivity of Goat Meat
• 2.4 ANISOTROPY IN GOAT MEAT
• 2.5 CONCLUSIONS
• CHAPTER 3 REDUCTION OF ESCHERICHIA COLI O157:H7 ON GOAT MEAT SURFACE WITH PULSED DC SQUARE WAVE SIGNAL
• 3.1 INTRODUCTION
• 3.2 MATERIALS AND METHODS
• 3.2.1 Electrical circuit
• 3.2.2 The Sample Holder
• 3.2.3 Preparation of the inoculum
• 3.2.4 Preparation of the meat samples
• 3.2.5 Inoculating the meat sample and the treatment procedure
• 3.2.6 Microbiological evaluation
• 3.2.7 Design of experiment
• 3.3 RESULTS AND DISCUSSION
• 3.3.1 Effects of the intensity of electric current
• 3.3.2 Effects of the frequency of the input signal and treatment duration
• 3.3.3 Effect of duty cycle of the input pulse train
• 3.3.4 Conclusions
• CHAPTER 4 RAPID DETECTION OF SALMONELLA TYPHIMURIUM IN CHICKEN CARCASS USING A SPR BIOSENSOR
• 4.1 INTRODUCTION
• 4.2 LITERATURE REVIEW
• 4.2.1 Current detection methods of microorganisms
• 4.2.2 SPR biosensor
• 4.3 METHODOLOGY
• 4.3.1 Materials
• 4.3.2 Methods for biosensor preparation
• 4.3.3 SPR biosensor assays
• 4.3.4 Experimental design
• 4.3.5 Statistical analysis
• 4.4 RESULTS
• 4.4.1 Initial tests with sugar and water solution
• 4.4.2 Tests from Salmonella Typhimurium in chicken carcass
• 4.5 CONCLUSIONS
• CHAPTER 5 VISCOSITY OF CAPRINE MILK WITH RESPECT TO FAT CONTENT, SHEAR RATE, AND TEMPERATURE
• 5.1 INTRODUCTION
• 5.2 MATERIALS AND METHODS
• 5.2.1 Milk and Cream Samples
• 5.2.2 Preparation of 1% and 2% Fat Milk
• 5.2.3 Instrument and Experimental Procedure
• 5.3 RESULTS AND DISCUSSION
• 5.3.1 Fat Composition in Milk and Cream Samples
• 5.3.2 Flow Characteristics of Milk Types and Cream
• 5.3.3 Effect of Shear Rat
• 5.3.4 Effect of Temperature
• 5.3.5 Effects of Fat Content on Viscosity
• 5.3.6 Variation of pH and Density in Caprine Milk
• 5.3.7 Rheological Models
• 5.4 CONCLUSIONS
• CHAPTER 6 SUMMARY OF DISSERTATION
• 6.1 OVERALL SUMMARY
• 6.2 RECOMMENDATION FOR FUTURE RESEARCH
• REFERENCES
• PUBLISHED PAPER
• ACKNOWLEDGEMENTS
• ABSTRACT
• 摘要