12 5 Oxidation, Premox, and Excessive Acetaldehyde 5.1 Introduction 5.2 Oxidation in Must and Wine 5.3 Sensory Characteristics and Detection of Excess Acetaldehyde and Oxidation in Wine 5.4 Deliberately Oxidised and Highly Oxygenated Wines 5.5 Metal Ions and Substrates for Oxidation 5.6 Enzymatic Oxidation 5.7 Chemical Oxidation 5.8 Microbial Oxidation 5.9 Acetaldehyde 5.10 Sotolon 5.11 Oxygen Management in Winemaking 5.12 Oxygen Uptake During Cellar Operations 5.13 Containers and Closures 5.14 Pinking 5.15 Premature Oxidation (Premox) 5.16 Prevention of Excess Acetaldehyde and Oxidation 5.17 Additions of Ascorbic Acid: Antioxidant or Oxidising Agent? 5.18 Laboratory Analysis 5.19 Treatments 5.20 Final Reflections References
13 6 Excessive Sulfur Dioxide, Volatile Sulfur Compounds, and Reduced Aromas 6.1 Introduction 6.2 The Presence and Role of Sulfur, Sulfur Dioxide, Sulfite, and Sulfate in Wine Production 6.3 Excessive Sulfur Dioxide 6.4 Oxygen Management in Winemaking 6.5 Reduction in Wine: Positive and Negative 6.6 Hydrogen Sulfide 6.7 Prevention of Hydrogen Sulfide Formation 6.8 Treatment for Hydrogen Sulfide in Wine 6.9 Mercaptans, Sulfides, Disulfides, Trisulfides, and Thioesters 6.10 Post‐bottling Reduction 6.11 Lightstrike 6.12 Laboratory Analysis for Sulfur Dioxide, Hydrogen Sulfide, and Volatile Sulfur Compounds 6.13 Final Reflections References
14 7 Excessive Volatile Acidity and Ethyl Acetate 7.1 Introduction 7.2 Volatile Acidity and Ethyl Acetate 7.3 The Controversy of High Levels of Volatile Acidity 7.4 Fixed Acids and Volatile Acids 7.5 Sensory Characteristics and Detection of Volatile Acidity 7.6 Legal Limits 7.7 Acetic Acid Bacteria 7.8 Production of Acetic Acid in Wine 7.9 Ethyl Acetate 7.10 Prevention of Excessive Volatile Acidity and Ethyl Acetate 7.11 Laboratory Analysis 7.12 Treatments 7.13 Final Reflections References
15 8 Atypical Ageing (ATA) – Sometimes Called Untypical Ageing (UTA) 8.1 Introduction 8.2 The Atypical Ageing Controversy 8.3 The Causes of Atypical Ageing and Formation Pathways 8.4 Sensory Detection 8.5 Laboratory Detection 8.6 The Main Viticultural Causes of ATA 8.7 Prevention 8.8 Treatments 8.9 Final Reflections References
16 9 Fermentation in Bottle 9.1 Introduction 9.2 Sensory Detection