Sterilization and Preservation: Applications of Supercritical Carbon Dioxide

Preface
Contents
1 Introduction to Sterilization and Preservation Using Supercritical CO2
	1.1 Relevance of Sterilization and Preservation of Food Products
		1.1.1 Scope of Sterilization and Preservation
		1.1.2 Need for a Green Effective Technology in Food Industries
	1.2 Relevance of Sterilization in Medical Industries
		1.2.1 Emergence of New Biomaterials
		1.2.2 Need for a Green Effective Technology for Biomaterials and Medical Devices
	1.3 Relevance of Sterilization with ScCO2 for Management of Clinical Solid Wastes
	References
2 Classification of Foods, Biomaterials, and Microorganisms
	2.1 Food Constituents
		2.1.1 Water
		2.1.2 Minerals
		2.1.3 Carbohydrates
		2.1.4 Fats and Lipids
		2.1.5 Organic Acids
		2.1.6 Nitrogen Containing Substances
		2.1.7 Vitamins
		2.1.8 Proteins
		2.1.9 Enzymes
			2.1.9.1 Pectin esterase
			2.1.9.2 Polygalacturonase
			2.1.9.3 Polyphenol oxidase
			2.1.9.4 Lipoxygenase
			2.1.9.5 Actions and Protein Structure of Enzymes
	2.2 Classification of Foods by Characteristic Properties
		2.2.1 Texture
		2.2.2 Color
		2.2.3 Flavor
		2.2.4 Nutritional Aspects
		2.2.5 Food Extracts and Phyto-Pharmaceuticals
		2.2.6 Safety, Diversity and Complexity
	2.3 Factors Causing Degradation and Spoilage of Foods
		2.3.1 Physical Factors
		2.3.2 Chemical Factors
		2.3.3 Microorganisms
	2.4 Undesirable Enzymes and Hurdles in Food Industry
	2.5 Classification of Biomaterials by their Activity
		2.5.1 Natural Polymers
		2.5.2 Artificial Polymers
		2.5.3 Medical Implants
	2.6 Microorganisms Involved in Contamination of Biomaterials
		2.6.1 Sources of Contamination
		2.6.2 Classification of Agents of Contamination
			2.6.2 1 Prions
			2.6.2.2 Endotoxins
	2.7 Contamination from Clinical Waste and Microflora
		2.7.1 Contaminants in Clinical Solid Waste
		2.7.2 Contaminants in Liquid Medical Waste
	References
3 Characterization Methods and Evaluation of Sterility
	3.1 Relevance of Microbial analysis in Food Industry
		3.1.1 Sources of Contamination
		3.1.2 Standard Testing Methods for Microbes
			3.1.2.1 Culture-based Methods
			3.1.2.2 Culture-independent Methods
		3.1.3 Environment Scanning Electron Microscope (ESEM)
		3.1.4 Limits of Detection and Requirements of Inactivation
		3.1.5 Standard Testing Methods for Enzyme Activity
			3.1.5.1 Color Measurement
			3.1.5.2 H-NMR Analysis of Polysaccharides
			3.1.5.3 Lipoxygenase Assay
			3.1.5.4 Trypsin Inhibitor Assay
			3.1.5.5 Free Fatty Acid Analysis
	3.2 Relevance of Microbial analysis in Biomaterials
		3.2.1 Factors for Contamination
		3.2.2 Detection and Testing Methods
		3.2.3 Standards of Sterility and Sterilization Efficiency
	3.3 Standards of Sterility Levels for Clinical Waste Management
	References:
4 Conventional Processes for Sterilization and Preservation
	4.1 Food Preservation
	4.2 Food Preservation Techniques
		4.2.1 Reduction in Temperature
		4.2.2 Reduction in pH
		4.2.3 Reduction in Oxygen Level in Modified Atmosphere
		4.2.4 Reduction of Water Activity
		4.2.5 Application of Heat
		4.2.6 Irradiation with Radionucleotide
		4.2.7 Pulsed Electric Field and High Voltage Arch Discharge
		4.2.8 Ultrahigh Pressure and Ultrasound
		4.2.9 Plasma
		4.2.10 Oscillating Magnetic Field
	4.3 Sterilization of Biomaterials and Medical devices
		4.3.1 Thermal Sterilization
		4.3.2 Ethylene Oxide (ETO) Gas Sterilization
		4.3.3 Vaporized Hydrogen Peroxide (VHP) Sterilization.
		4.3.4 Hydrogen Peroxide Gas Plasma Sterilization
		4.3.5 Peracetic Acid Sterilization
		4.3.6 Ozone Immersion Sterilization
		4.3.7 High Energy-Gamma Irradiation
		4.3.8 Electron Beam (E-Beam) Sterilization:
		4.3.9 Microwave Sterilization
	4.4 Safety and Effectiveness of the Processes
	References
5 Processing with Supercritical Carbon Dioxide
	5.1 Unique Advantages of SCCO2-based-Technologies
	5.2 Characteristics of Supercritical Carbon Dioxide
		5.2.1 Path for Attaining Supercritical State
		5.2.2. Unique Advantages and Properties As a Solvent
	5.3 Supercritical Fluid Extraction Process
	5.4 Commercial Scale Supercritical Fluid Extraction Process
	5.5 Commercial Applications of SCF Extraction from Natural Products
	5.6 Other SCCO2- based Processes
		5.6.1 Micronization, Microencapsulation, and Impregnation for Drug Delivery
		5.6.2 Synthesis of Novel Materials, Specialty Chemicals and Polymers in ScCO2-Medium
		5.6.3 Biochemical Reactions in ScCO2
	5.7 Conclusion
	References:
6 Sterilization and Preservation of Solid Foods with Supercritical CO2
	6.1 Performance Evaluation of scCO2 for Sterilization and Stabilization
		6.1.1 Sterilization and Stabilization of Rice Bran
		6.1.2 Sterilization and Stabilization of Soybeans
	6.2 Sterilization of Wheat
	6.3 Sterilization of Coconut
	6.4 Sterilization of Meats
	References:
7 Sterilization and Preservation of Liquid Foods Using Supercritical CO2
	7.1 Tomato Puree
		7.1.1 Characteristics of Tomato Juice
		7.1.2 Conventional Preservation Processes
		7.1.3 Preservation by Treatment with ScCO2
	7.2 Sugarcane Juice
		7.2.1 Characteristics of Sugarcane Juice
		7.2.2 Conventional Preservation Methods
		7.2.3 Preservation and Stabilization with ScCO2
	7.3 Aloe Vera Juice
		7.3.1 Characteristics of Aloe Vera Juice
		7.3.2 Preservation of Aloe Vera Juice
		7.3.3 Preservation and Stabilization of Aloe Vera Juice with ScCO2
	7.4 Cow Milk
		7.4.1 Characteristics of Cow Milk
		7.4.2 Preservation and Pasteurization of Milk
		7.4.3 Preservation of Cow Milk by ScCO2 Treatment
	7.5 Apple Juice
		7.5.1 Characteristics
		7.5.2 Conventional Preservation Process
		7.5.3 Preservation with ScCO2 Treatment
	References
8 Mechanism of Sterilization and Preservation Using Supercritical CO2
	8.1 Bactericidal Effect of CO2
	8.2 Mechanism for Inactivation of Vegetative Microorganisms
		8.2.1 Cell Wall Rupture
		8.2.2 Physiological Inactivation
		8.2.3 Biological stress
	8.3 Inactivation Mechanism of Bacterial Spores
	8.4 Mechanism of Virus inactivation
	8.5 Mechanism of Inactivation of Enzymes
		8.5.1 Inhibitory Effect of Molecular CO2
		8.5.2 Effect of Characteristics of ScCO2
		8.5.3 Effect of Pressurization-Depressurization Cycling
	References:
9 Sterilization of Biomaterials and Medical Devices with Supercritical CO2
	9.1 Safety and Success of Medical Devices
	9.2 Methods of Contamination and Infectious agents
	9.3 Factors Involved in Sterilization of Biomaterials
	9.4 Current Methods of Sterilization and Disinfection
	9.5 Terminal Sterilization Using ScCO2
	9.6 Effectiveness of ScCO2 Treatment of Biomaterial with Select Additives
	9.7 Inactivation of Virus
	9.8 Sterilization process for rapid inactivation of bacterial endospores
	9.9 Elimination of Endotoxins and Pyrogens
	9.10 Sterilization of Biologically Active Large Molecules and Implant Materials
	References:
10 Clinical Sold Waste Management with ScCO2 Sterilization Technology
	10.1 Generation, Handling, and Safe Disposal of Clinical Solid Wastes
	10.2 Recycle-Reuse of CSW after Sterilization
	10.3 Pathogenic Microorganisms Present in Clinical Wastes
		10.3.1 Pathogenic Bacteria in Clinical Wastes
		10.3.2 Infectious Fungi in Clinical Wastes
	10.4 Thermal methods for Inactivation and Neutralization
		10.4.1 Incineration
		10.4.2 Steam Sterilization
	10.5 Nonthermal Sterilization Technology Using Supercritical CO2
		10.5.1 Inactivation of Micro-Organisms Using ScCO2
		10.5.2 Inactivation of Fungi Using ScCO2
	10.6 Sterilization-Reuse of Personal Protective Equipment (PPE) Using scCO2 Technology
	10.7 Environment and Health Protection Using scCO2 Sterilization Technology
	References: