THE CHEMISTRY OF GAS MANUFACTURE: MATERIALS AND PROCESSES
CONTENTS PART 1: NOVEL AND CONVENTIONAL SAMPLE PREPARATION PROCESSES CHAPTER HEADSPACE SAMPLING: AN “EVERGREEN” METHOD IN CONSTANT EVOLUTION TO CHARACTERIZE FOOD FLAVORS THROUGH THEIR VOLATILE FRACTION 11 FOOD ANALYSIS AND THE VOLATILE FRACTION: A GENERAL INTRODUCTION 111 HEADSPACE SAMPLING MODES 112 HEADSPACE SAMPLING: A SHORT HISTORY AND RECENT EVOLUTION 113 DYNAMIC HEADSPACE SAMPLING 114 STATIC AND TRAPPED HEADSPACE 115 HIGH- CONCENTRATION CAPACITY HEADSPACE TECHNIQUES 116 HEADSPACE AND VOLATILE QUANTITATION 117 A SHORT OVERVIEW OF THE S- HS AND HCC- HS QUANTITATION APPROACHES 118 HEADSPACE AS A TOOL FOR FINGERPRINTING AND PRO?LING 115 CONCLUSIONS LIST OF ABBREVIATIONS REFERENCES VIII CHAPTER SAMPLE PREPARATION FOR THE GAS CHROMATOGRAPHY ANALYSIS OF SEMI- VOLATILES AND NON- VOLATILE COMPOUNDS IN FOOD SAMPLES 21 INTRODUCTION 22 EXTRACTION TECHNIQUES IN USE FOR FOOD ANALYSIS 221 EXTRACTION TECHNIQUES FOR THE TREATMENT OF LIQUID SAMPLES 222 EXTRACTION TECHNIQUES FOR THE TREATMENT OF SOLID SAMPLES 223 DERIVATIZATION 23 REPRESENTATIVE APPLICATIONS 231 MICROCONTAMINANTS 232 PROCESS- GENERATED FOOD TOXICANTS 233 CARBOHYDRATES 234 FATTY ACIDS ACKNOWLEDGMENTS PART 2: CONVENTIONAL GAS CHROMATOGRAPHY CHAPTER CONVENTIONAL GAS CHROMATOGRAPHY: BASIC PRINCIPLES AND INSTRUMENTAL ASPECTS 31 INTRODUCTION 32 BASIC PRINCIPLES 321 RETENTION 322 BAND BROADENING 323 RESOLUTION 33 SAMPLE INTRODUCTION 331 HOT VAPORIZING INJECTORS 332 COLD ON- COLUMN INJECTORS 333 PROGRAMMED- TEMPERATURE VAPORIZER INJECTORS 334 LARGE- VOLUME INJECTION 34 COLUMN TECHNOLOGY 341 WALL- COATED OPEN- TUBULAR COLUMNS 342 STATIONARY PHASES 343 CHIRAL STATIONARY PHASES 344 POROUS- LAYER OPEN- TUBULAR COLUMNS 35 DETECTION OPTIONS 351 IONIZATION DETECTORS IX 352 BULK PROPERTY DETECTORS 353 OPTICAL DETECTION CHAPTER CONVENTIONAL GAS CHROMATOGRAPHY: MASS SPECTROMETRY HYPHENATION AND APPLICATIONS IN FOOD ANALYSIS 41 GAS CHROMATOGRAPHY– MASS SPECTROMETRY: INTRODUCTION 42 GAS CHROMATOGRAPHY– MASS SPECTROMETRY: PRINCIPLES AND INSTRUMENTATION 421 IONIZATION METHODS 422 MASS ANALYZERS 43 APPLICATIONS IN FOOD ANALYSIS USING GC- MS 431 SINGLE QUADRUPOLE MS APPLICATIONS 432 TIME- OF- ?IGHT MS APPLICATIONS 433 TRIPLE QUADRUPOLE MS APPLICATIONS 434 HYBRID MS APPLICATIONS PART 3: HIGH- SPEED GAS CHROMATOGRAPHY CHAPTER HIGH- SPEED GAS CHROMATOGRAPHY: BASIC THEORY, GENERAL PRINCIPLES, PRACTICAL ASPECTS AND FOOD ANALYSIS 51 INTRODUCTION 52 BASIC THEORY, GENERAL PRINCIPLES, PRACTICAL ASPECTS AND FOOD ANALYSIS 521 MICRO- BORE COLUMNS 522 VACUUM OUTLET CONDITIONS 523 RESISTIVE COLUMN HEATING 524 SHORT CAPILLARY COLUMNS PART 4: TWO- DIMENSIONAL GAS CHROMATOGRAPHY- BASED PROCESSES: PRINCIPLES, PRACTICAL ASPECTS AND APPLICATIONS IN FOOD ANALYSIS CHAPTER HEART- CUTTING TWO- DIMENSIONAL GAS CHROMATOGRAPHY 61 DE?NITIONS AND FUNDAMENTAL CONSIDERATIONS X 62 TECHNICAL IMPLEMENTATIONS FOR H/ C MDGC 63 OPTIMIZATION IN MDGC APPLICATIONS 631 BENE?TS OF NARROW HEART- CUT WINDOWS 632 OVERCOMING LOSS OF SELECTIVITY WITH WIDE HEART- CUT WINDOWS IN THE FIRST DIMENSION BY MS DETECTION 64 APPLICATIONS OF H/ C MDGC IN FOOD AND FLAVOR ANALYSIS 65 MULTIDIMENSIONAL GC IN AUTHENTICITY CONTROL: ENANTIOSELECTIVITY AND ISOTOPE DISCRIMINATION 66 PREPARATIVE H/ C MDGC 67 FUTURE PERSPECTIVES: CHIP- BASED MDGC COMPREHENSIVE TWO- DIMENSIONAL GAS CHROMATOGRAPHY 71 INTRODUCTION 72 BASIC THEORY, GENERAL PRINCIPLES, PRACTICAL AND INSTRUMENTAL ASPECTS 721 MODULATION TECHNIQUES 722 COLUMN OPTIMIZATION ASPECTS 723 DETECTION 73 APPLICATIONS IN THE FIELD OF FOOD ANALYSIS 731 MASS SPECTROMETRY DETECTION 732 OTHER DETECTORS 733 HYBRID MULTIDIMENSIONAL GAS CHROMATOGRAPHY 74 CONCLUSIONS MULTIDIMENSIONAL LC- GC 81 INTRODUCTION 811 WHY ONLINE LC- GC? 812 HISTORY OF ONLINE LC- GC 82 CONCEPTS FOR THE GC INTRODUCTION OF LARGE SAMPLE VOLUMES 821 SPLIT/ SPLITLESS INJECTION XI 83 ON- COLUMN TECHNIQUES 831 SOLVENT TRAPPING FOR VOLATILE SOLUTES 832 RECONCENTRATION BY THE RETENTION GAP EFFECT 833 SOLVENT VAPOR EXIT 834 PARTIALLY OR FULLY CONCURRENT ELUENT EVAPORATION? 835 GAS DISCHARGE VERSUS OVER?OW 84 PROBLEMS WITH WATER- CONTAINING ELUENTS 85 INTERFACES FOR ONLINE TRANSFER THE Y- INTERFACE PTV INJECTOR THROUGH OVEN TRANSFER ADSORPTION DESORPTION INTERFACE VAPORIZER CHAMBER/ PRE- COLUMN SOLVENT SPLIT INTERFACE 86 OTHER INTERFACES ON- COLUMN INJECTOR LOOP- TYPE INTERFACE WIRE INTERFACE SWING INTERFACE 87 LC- GC INSTRUMENTATION 88 HPLC PRE- SEPARATION 89 SUMMARIZED DESCRIPTION OF THE TWO PREFERRED TRANSFER TECHNIQUES PARTIALLY CONCURRENT EVAPORATION WITH THE Y- INTERFACE CONCURRENT ELUENT EVAPORATION WITH THE Y- INTERFACE 810 APPLICATIONS MINERAL HYDROCARBONS IN FOOD AND RELATED SAMPLES ANALYSIS OF MINERAL OIL PRODUCTS ENVIRONMENTAL CONTAMINANTS DETERMINATION OF FOOD IRRADIATION STERENES IN EDIBLE OILS STEROLS IN THE UNSAPONI?ABLE FRACTION OF EDIBLE OILS ISOMERIZATION OF ?7 STEROLS MINOR COMPONENTS IN EDIBLE OILS METHYL- , ETHYL- AND WAX ESTERS IN OLIVE OIL 81010 NERVONIC ACID IN MEAT- DERIVED FOODS 81011 EPOXIDIZED SOYBEAN OIL XII 81012 PESTICIDE RESIDUES 81013 MIGRATION OF TRIMELLITIC ACID INTO FOOD 81014 FLAVOR COMPOUNDS 81015 PHARMACEUTICAL PRODUCTS 81016 ORGANIC COMPOUNDS IN WATER 81017 POLYMERS AND ADDITIVES 81018 COMPREHENSIVE TWO- DIMENSIONAL LC- GC 811 CONCLUSIONS PART 5: GAS CHROMATOGRAPHY– OLFACTOMETRY CHAPTER GAS CHROMATOGRAPHY– OLFACTOMETRY: PRINCIPLES, PRACTICAL ASPECTS AND APPLICATIONS IN FOOD ANALYSIS 91 INTRODUCTION 92 THE PRINCIPLE OF GAS CHROMATOGRAPHY– OLFACTOMETRY 93 GC- O: PRACTICAL ASPECTS 931 SAMPLE INTRODUCTION 932 COLUMN PARAMETERS 933 EF?UENT SPLITTING AND SNIF?NG SYSTEMS 934 THE SNIFFER IN ITS ROLE AS HUMAN GC DETECTOR 94 SAMPLE PREPARATION TECHNIQUES PRECEDING GC- O 941 SAMPLE HOMOGENIZATION 942 STEAM DISTILLATION 943 SOLVENT EXTRACTION METHODS 944 SOLVENT- FREE EXTRACTION APPROACHES 945 HEADSPACE SAMPLING TECHNIQUES 946 SAMPLE PREPARATION TECHNIQUES – CONCLUSION 95 ODORANT RANKING APPROACHES IN GC- O 951 ODORANT RANKING BY INTENSITY MEASUREMENT 952 ODORANT RANKING BY DETECTION FREQUENCY 953 ODORANT RANKING BY DILUTION TO THRESHOLD 96 STRUCTURE ASSIGNMENT OF ODORANTS DETECTED BY GC- O 97 GC- O DATA INTERPRETATION AND SUBSTANTIATION 971 LIMITATIONS OF GC- O RESULTS 972 ODORANT QUANTITATION AND CALCULATION OF ODOR ACTIVITY VALUES 973 ODOR RECONSTITUTION AND OMISSION EXPERIMENTS 98 APPLICATIONS OF GC- O IN FOOD ANALYSIS 981 USING GC- O TO DISCOVER NOVEL ODOR- ACTIVE COMPOUNDS IN FOODS XIII 982 USING GC- O TO SUBSTANTIATE VARIETAL AROMA DIFFERENCES 983 USING GC- O TO SUBSTANTIATE OFF- FLAVORS IN FOOD 984 USING GC- O FOR THE TARGETED OPTIMIZATION OF FOOD PROCESSING 985 USING GC- O FOR THE APPROXIMATION OF ODOR THRESHOLD VALUES IN AIR 99 CONCLUSION AND PERSPECTIVE PART 6: CHEMOMETRICS CHAPTER 10 CHEMOMETRICS: BASIC PRINCIPLES AND APPLICATIONS 101 BASIC PRINCIPLES 1011 MULTIVARIATE DESIGN OF EXPERIMENTS 1012 DATA PRETREATMENT 1013 PATTERN RECOGNITION METHODS 1014 CLASSI?CATION AND CLASS- MODELING METHODS (SUPERVISED PATTERN RECOGNITION) 1015 REGRESSION METHODS (SUPERVISED PATTERN RECOGNITION) 102 APPLICATIONS IN FOOD ANALYSIS INVOLVING 1D AND 2D GC SEPARATIONS 1021 MULTIVARIATE DESIGN OF EXPERIMENTS IN FOOD ANALYSIS 1022 CHEMOMETRICS IN FOOD ANALYSIS DATA ELABORATION: OVERVIEW 1023 DATA ANALYSIS CHALLENGES IN OMICS INVESTIGATIONS 1024 FUTURE PERSPECTIVES AND INNOVATIVE APPROACHES ACKNOWLEDGMENT