Analysis of Nonalcoholic Beverages

The Enzyme-Linked Immunosorbent Assay (ELISA) in the Beverage Industries: Principles and Practice.- 1 Introduction.- 2 Basic ELISA Procedures for Detection of Antigens.- 2.1 The Double Antibody Sandwich Techniqu.- 2.2 The Immunoenzymometric Assa.- 2.3 Competitive ELISA with Labeled Antigen.- 2.4 Amplification System.- 2.5 Comparison of Method.- 3 Materials, Protocols and Comments.- 3.1 Antibodies, Enzymes and Special Equipmen.- 3.2 Conjugation of Enzymes to Proteins and Hapten.- 3.3 Biotinylation.- 3.4 Coating the Solid Phase.- 3.5 Enzyme Substrates.- 3.6 Sample Preparation.- 3.7 Washing Procedure.- 3.8 Adjustment of Assay Conditions.- 4 Concluding Remarks.- References.- Carboxylic Acids in Soft Drinks.- 1 Introduction.- 2 Analytical Method.- 2.1 Gas Chromatography.- 2.1.1 Analysis of Butyl Derivatives of Carboxylic Acids by Yamashita et al. (1973).- 2.1.2 Analysis of Trimethylsilyl Derivatives of Carboxylic Acids by the Ministry of Health and Welfare in Japan (1982).- 2.1.3 Simultaneous Analysis of Carboxylic Acids Used as Preservatives and Acidulants by Tsuda et al. (1985).- 2.1.4 Analysis of Carboxylic Acids Used as Preservatives by the Ministry of Health and Welfare in Japan (1982).- 2.1.5 Analysis of Sorbic Acid and Benzoic Acid After Extrelut Column Cleanup by Coelho and Nelson (1983).- 2.1.6 Analysis of Benzoic Acid and Sorbic Acid as Trimethylsilyl Esters by the NMKL-AOAC Method (Larsson 1983).- 2.2 Ion-Exchange Chromatography.- 2.2.1 Analysis by Highly Efficient Carboxylic Acid Analyzer by Nakajima et al. (1976).- 2.2.2 Other Methods.- 2.3 High-Performance Liquid Chromatography.- 2.3.1 Method by Palmer and List (1973).- 2.3.2 Method by Coppola et al. (1978).- 2.3.3 Method by Ashoor and Knox (1984).- 2.3.4 Analysis of Benzoate in Soda Beverages by the AOAC Method (Woodward et al. 1979).- 2.3.5 Analysis of Sorbic Acid and Benzoic Acid by Ueda and Mazaki(1976).- 2.3.6 Analysis of Carboxylic Acids After Derivatization with Phenacyl Bromide by Mentasti et al. (1985).- 2.3.7 Analysis of Carboxylic Acids as Their p-Nitrobenzyl Esters by Badoud and Pratz (1986).- References.- Amino Acid Pattern for Analysis of Fruit Juice Authenticity.- 1 Introduction.- 2 Development of Inspection Methods for Detecting Adulteration of Fruit Juices or for Testing Their Authenticity.- 3 Sample Preparations for the Analysis of Amino Acids Distribution Pattern in Fruit Juice.- 3.1 Amino Acid Distribution Pattern for the Analysis of Lemon Juice Authenticity.- 3.2 Amino Acid Distribution Pattern for Checking Beverage Authenticity of Commercial Lemon and Honey-Lemon Juice.- 3.3 Verification of Orange Juice Authenticity by the Amino Acid Pattern Checking Method.- 3.4 Amino Acid Pattern Used for Analyzing the Authenticity of Passion Fruit Juice.- 4 Distribution Order of Abundance of Free Amino Acids Used for Checking Fruit Juice Authenticity.- References.- Spectral Characteristics of Citrus Products.- 1 Introduction.- 2 Absorption Spectra.- 2.1 Citrus Juices.- 2.2 Citrus By-Products.- 3 Conclusion.- References.- Bitterness in Fruit Juices: Assay of Bitter Principles in Citrus Juices.- 1 Bitterness in Fruit Juices.- 1.1 Bitter Principles in Citrus Juices.- 2 Assay of Limonoid Bitter Principles in Citrus Juices.- 2.1 Sample Preparation for TLC and HPLC: General Considerations.- 2.2 Thin-Layer Chromatographie Assay of Limonoids in Citrus Juices.- 2.2.1 Maier and Grant Method (1970).- 2.2.2 Modified Chandler and Kefford Method (1966).- 2.2.3 Tatum and Berry Direct Spotting Method (1973a).- 2.3 High-Pressure Liquid Chromatographie Assay of Limonoids.- 2.3.1 Rouseff and Fisher Method (1980).- 2.3.2 Shaw and Wilson Method (1984).- 2.4 Immunoassay Techniques for Assay of Limonin.- 2.4.1 Enzyme Immunoassay of Limonin in Citrus Juices.- 2.5 Supply of Limonin.- 3 Assay of Flavonoid Bitter Principles in Citrus Juices.- 3.1 Colorimetric and Spectrophotometric Methods.- 3.1.1 Davis Method (1947).- 3.1.2 Other Colorimetric Methods.- 3.1.3 Ultraviolet Absorption Method (Hendrickson et al. 1958).- 3.2 Thin-Layer Chromatography of Flavonoid Bitter Principles.- 3.2.1 Hagen et al. Method (1965).- 3.2.2 Fisher et al. Method (1966).- 3.2.3 Tatum and Berry Method (1973b).- 3.3 High-Pressure Chromatography of Flavonoid Bitter Principles.- 3.3.1 Fisher and Wheaton Method (1976).- References.- Analytical Methods for Orange Juice Volatiles.- 1 Introduction.- 2 The Volatile Fraction of Orange Juice.- 3 Raw Material for Orange Juice Volatiles Analysis.- 4 Global Methods of Analysis.- 5 Separative Analysis. Gas Chromatography.- 5.1 Gas Chromatographic Analysis Without Sample Preparation.- 5.1.1 Direct Injection of Juice.- 5.1.2 Direct Headspace Analysis.- 5.2 Sample Preparation for Gas Chromatographic Analysis Isolation and Concentration Techniques.- 5.2.1 Solvent Extraction.- 5.2.2 Use of an Inert Gas Sweeping the Headspace or Stripping the Juice.- 6 Future Research.- References.- Stable Carbon Isotope Ratios for Detecting Added Sugars in Orange and Apple Juices and Added Citric Acid in Lemon Juices.- 1 Introduction.- 2 Photosynthetic Fractionation of Carbon Isotopes in Source CO2.- 2.1 Instrumentation and the Concept of [(?-13C] Values.- 2.2 C3 (Calvin) Plants.- 2.3 C4 (Hatch-Slack) Plants.- 2.4 CAM (Crassulacean Acid Metabolism) Plants.- 2.5 Additional Factors Contributing to Plant [?-13C] Values.- 2.5.1 Carbon Dioxide Diffusional Effects on Plant [?5-13C] Values.- 2.5.2 Variations Among Classes of Plant Compounds.- 3 Food Applications of Source Variations in [?- 13C] Values.- 3.1 Detecting Mixtures of C3 and C4 Plant-Derived Foods.- 3.1.1 Cane and High Fructose Corn Syrups in Orange Juice.- 3.1.2 Cane and High Fructos Corn Syrups in Apple Juice.- 3.1.3 Citric Acid in Lemon Juice.- 4 Conclusion.- 4.1 Potential Future Applications of Isotope Ratios.- References.- Analytical Methods for Tomato Products.- 1 Contribution of Fruit Components to Quality.- 1.1 Fresh Tomatoes.- 1.2 Paste.- 1.3 Whole Peeled and Diced Tomatoes.- 1.4 Juice.- 1.5 Catsup and Sauces.- 1.6 Soups.- 2 Tomato Composition.- 2.1 Sugars.- 2.2 Polysaccharides.- 2.3 Proteins.- 2.4 Amino Acids.- 2.5 Ash.- 2.6 Organic Acids.- 2.7 Ascorbic Acid.- 2.8 Carotenoids.- 2.9 Other Compounds.- 3 Analytical Methods.- 3.1 Total Solids.- 3.2 Total Sugars.- 3.3 Reducing Sugars.- 3.4 Individual Sugars.- 3.5 Carbohydrate Polymers.- 3.5.1 Insoluble Solids.- 3.5.2 Fractionation of Polysaccharide Polymers.- 3.5.3 Firmness.- 3.5.4 Consistency.- 3.5.5 Precipitate Weight Ratio.- 3.6 Protein.- 3.7 Amino Acids.- 3.8 Ash.- 3.9 Organic Acids.- 3.9.1 Titratable Acidity.- 3.9.2 Total Acidity.- 3.9.3 Individual Acids.- 3.10 Ascorbic Acid.- 3.11 Color and Carotenoids.- 3.12 Volatiles.- 3.13 ?-Tomatine.- References.- Liquid Chromatographic Determination of Quinine, Hydroquinine, Saccharin, and Sodium Benzoate in Quinine Beverages.- 1 Abstract.- 2 Introduction.- 3 Method.- 3.1 Apparatus.- 3.2 Reagents.- 3.3 Calculation of Hydroquinine in Quinine Sulfate Standard.- 3.4 Sample Preparation.- 3.5 Determination.- 3.6 Calculations.- 3.7 Calculation of Other Food Additives.- 4 Results and Discussion.- References.- Formaldehyde in Coffee.- 1 Introduction.- 2 Formaldehyde in Common Foods.- 3 Analytical Methods for Formaldehyde.- 3.1 Colorimetric Method.- 3.2 High-Performance Liquid Chromatographie (HPLC) Method.- 3.3 Gas Chromatographie (GC) Method.- 3.4 Thiazolidine Derivative Method.- 4 Determination of Formaldehyde in Coffee.- 4.1 General Considerations.- 4.2 Analytical Methods Using Thiazolidine.- References.- Metabolism and Analysis of Caffeine and Other Methylxanthines in Coffee, Tea, Cola, Guarana and Cacao.- 1 Introduction.- 2 Occurrence.- 2.1 Studies in Plants in the 1980?s.- 3 Metabolism of Caffeine in Caffeine-Containing Plants.- 3.1 Caffeine Biosynthesis and C1 Metabolism.- 3.2 Caffeine Biosynthesis and Purine Metabolism.- 3.3 Caffeine Biosynthesis: Compartmentation of Purine de Novo Biosynthesis and Salvage Pathways.- 3.4 Caffeine Biosynthesis in Vitro with Enzyme Preparations.- 3.5 Biodegradation and Biotransformation of Purine Alkaloids.- 3.6 Caffeine Metabolism in In-Vitro Plant Cultures.- 3.7 Translocation, Accumulation and Other Aspects.- 4 Analysis for Purine Alkaloids in Plants and Foods.- 4.1 Handling and Storage of the Plant Material.- 4.2 Extraction.- 4.2.1 Leaf Material.- 4.2.2 Fruit, Seed and Other Plant Material.- 4.2.3 Food Material.- 4.3 Chromatographic Analyses.- 4.3.1 Paper Chromatography.- 4.3.2 Thin-Layer Chromatography.- 4.3.3 Gas Chromatography and Gas Chromatography/Mass Spectrometry.- 4.3.4 High-Performance Liquid Chromatography.- 5 Biochemical Methods Used to Study Purine Alkaloid Metabolism in Plants.- 5.1 Isotopically Labeled Substrates and Related Analysis.- 5.1.1 One-Carbon Compounds or Fragments as Precursors for Caffeine Biosynthesis.- 5.1.2 Purine Compounds as Precursors for Caffeine Biosynthesis.- 5.1.3 Caffeine as Precursor for the Synthesis of Dimethylxanthines or Methyluric Acids.- 5.2 Enzymes Involved in Caffeine Metabolism.- 5.2.1 Extraction of Af-Methyltransferases from Tea and Coffee Leaves (Suzuki and Takahashi 1975a; Negishi et al. 1985b, c).- 5.2.2 Extraction of N-Methyltransferase(s) from Coffee Fruits (Roberts and Waller 1979).- 5.2.3 Assay for N-Methyltransferase Activity (Suzuki and Takahashi 1975a; Roberts and Waller 1979; Negishi et al. 1985b, c).- 5.3 Cultured Cells as Useful Tools for Studying Purine Alkaloid Metabolism.- 6 Conclusions.- References.- Colour and Flavour Characteristics of Made Tea.- 1 Introduction.- 2 Tea Husbandry.- 2.1 Vegetative Propagation.- 2.2 Flush Character of Harvest.- 2.3 Fine or Coarse Plucking.- 2.4 Plucking and Productivity.- 2.5 Characteristics of Various Clones.- 2.6 Phytohormones.- 2.6.1 Bioassay for Brassinosteroids.- 2.7 Analytical Methods.- 2.7.1 Moisture Analysis.- 2.7.2 Tea-Soluble Solid (TSS) Estimation.- 2.7.3 Estimation of Chlorophylls (Harborne 1973).- 2.7.4 Estimation of Total Anthocyanin and Total Flavonol Glycoside (Francis 1982).- 2.7.5 Estimation of Catechins (Bhatia and Ullah 1968).- 2.7.6 Separation and Spectral Data of Catechins (Saijo 1982).- 2.7.7 Isolation of Flavone Glycosides (Takino 1972).- 2.7.8 GLC-MS Analysis of Instant Tea (Horvat and Senter 1980).- 3 Manufacture of Tea.- 3.1 Categories of Made Tea.- 3.2 Green Tea.- 3.3 Pouchong Tea (Oolong Tea).- 3.4 Black Tea.- 3.5 Amadori Products (RP).- 3.6 Shelf Life.- 3.7 Raw Materials and Processed Product.- 3.8 Black Teas Manufactured from Different Components of a Shoot.- 3.9 Analytical Methods.- 3.9.1 Estimation of TF and TR (Roberts and Smith 1961; Ullah 1972).- 3.9.2 Flavognost Method (Pintauro 1977).- 3.9.3 Follin-Ciocalteu Reagent Test for Optimum Fermentation (Chakaravarty 1976).- 4 Colour of Made Tea.- 4.1 Processing and Colour Development.- 4.2 Theaflavins.- 4.3 Thearubigins.- 4.4 Cup Characteristics of Tea.- 4.5 Shade of Colour of Made Tea.- 4.6 Tea Fibres.- 4.7 Effect of Storage on Colours.- 4.8 Analytical Methods.- 4.8.1 Extraction and Isolation of Thearubigins (TR).- 4.8.2 Extraction and Estimation of Chlorophylls in Black Tea.- 4.8.3 Estimation of Caffeine in Tea Brew (Gogoi et al. 1984).- 4.8.4 Determination of Crude Fibre (Wood et al. 1964b).- 5 Volatile Flavour and Aroma Compounds of Made Tea.- 5.1 Sensory Evaluation of Volatiles.- 5.2 Precursors of Volatiles.- 5.3 Analytical Methods.- 5.3.1 Preparation of Steam-Distilled Volatile Concentrate.- 5.3.2 Identification and Quantification of Volatiles.- 5.3.3 Lipid Analysis (Wright and Fishwich 1979).- 5.3.4 Extraction, Isolation and Identification of Carotenoids (Harborne 1973).- 5.4 Plucking Standard and Flavour Volatiles.- 5.5 Varietal Differences and Flavour Volatiles.- 5.6 Relationship Between VFC, Lipid and Shoot Components.- 5.7 The Role of Technology in Flavour Genesis.- 5.8 Seasonal Changes and VFC.- 5.9 Influence of Location on Aroma Concentrate.- 5.10 Flavour of Various Teas.- 5.11 Volatiles in Orthodox and CTC Black Teas.- References.- Analysis of Black Tea Volatiles.- 1 Introduction.- 2 Composition of Black Tea Volatiles.- 2.1 Relations Between Black Tea Quality and Its Aroma Composition.- 3 Formation of Black Tea Volatiles.- 3.1 Hydrocarbons.- 3.2 Esters.- 3.3 Carbonyls.- 3.3.1 Aldehydes.- 3.3.2 Ketones.- 3.4 Alcohols.- 3.5 Phenols.- 3.6 Furans.- 3.7 Pyrroles.- 3.8 Pyridines.- 3.9 Pyrazines.- 3.10 Volatile Acids.- References.- Analysis of Cocoa Flavour Components and Flavour Precursors.- 1 Introduction.- 2 Precursors and Nonvolatile Flavour Components.- 2.1 The Significance of Nonvolatile Cocoa Bean Constituents to Flavour.- 2.1.1 Acids.- 2.1.2 Polyphenols and Phenolic Acids.- 2.1.3 Purin Alkaloids.- 2.1.4 Proteins and Proteolytic Products.- 2.1.5 Sugars.- 2.2 Methods of Isolation and Analysis.- 2.2.1 Sampling and Sample Preparation.- 2.2.2 Precursors of Chocolate Aroma.- 2.2.3 Acids.- 2.2.4 Polyphenols and Phenolic Acids.- 2.2.5 Purin Alkaloids.- 2.2.6 Proteins, Peptides, and Amino Acids.- 2.2.7 Sugars.- 3 Cocoa Flavour Volatiles.- 3.1 Development of Knowledge About Cocoa Flavour Volatiles.- 3.2 Estimation of Cocoa Flavour Volatiles.- 3.2.1 Introductory Remarks.- 3.2.2 Selection and Pretreatment of Samples.- 3.2.3 Isolation of Volatiles.- 3.2.4 Analysis.- 3.3 Examples of Application.- 3.3.1 Indicative Compounds.- 3.3.2 Rapid Routine Control Methods.- References.- The Importance of Plant Analysis to Food Regulation.- 1 Historical Background.- 2 Current Use of Analytical Methods.- 3 Food Standards and Food Labeling.- 4 Food Sanitation.- 5 Food Safety.- 6 Conclusion.- References.