ALTERNATIVE ANTI-OXIDANTS AND PRESERVATIVES IN WINE - THE VIABILITY OF ROOIBOS AND HONEYBUSH WOOD Francois Cillié August 2016 Dissertation submitted to the Cape Wine Academy in partial fulfilment of the requirements for the diploma of Cape Wine Master. Abstract The need to use additives in the winemaking process for preservation and anti-oxidant-related reasons has long been a well-known fact. Sulphur is by far the most commonly-used additive as it has both preservative and anti-oxidative properties. The use of sulphur has been a contentious subject for a long time, not only in the wine industry but also in the preservation of other consumables. In recent years, more and more consumers have developed an interest in how their daily consumables are produced. Many have become not only health-conscious but also knowledgeable, often taking a firm stance against high levels of artificial additives being used. In general, consumers would welcome more research into natural alternative additives. Due to increased scientific research and experimentation, numerous wine companies have incorporated such results into their marketing campaigns. There is a trend towards lower sulphur and no added sulphur wines which started with the organic winemaking revolution a few years ago. Criticism of high sulphur wines is on the rise, due to negative health effects on a small but growing proportion of the population. Prior research consists of additives and winemaking practises which could help achieve moderate but acceptable sulphur levels (or completely avoid adding any sulphur) without compromising quality, potential to mature or drastically changing the flavour profile of a wine. In reality, consumers very often indicate where their preferences lie. This, in turn, should indicate to producers where change is needed and what to focus on next. The current trend towards healthy living is prompting some producers to research alternative natural additives and adjust their winemaking techniques accordingly. The alternative discussed in this dissertation will concentrate on the use of wood from the unique and indigenous plants called rooibos (Aspalathus linearus) and honeybush (Cyclopia genistoides) instead of sulphur for preservative and anti-oxidative purposes. These plants have natural anti-oxidant properties and have proved through extensive research to be extremely effective in protecting wine against spoilage. Interviews were conducted, wine presentations were executed and a survey was sent out to wine industry-related researchers, producers, distributors, retailers and consumers to determine their experience and opinion on the subject. Their recommendations on how to ensure the initiative is successful are discussed. Three possible wine styles and marketing messages exist: Firstly the “no sulphur added’ message referring to a healthier choice. Secondly the “rooibos and honeybush wooded” message referring to a unique style and flavour of wine for those adventurous consumers. A third wine style could simply be that of producing wines which combine lower sulphur additions and the use of rooibos and honeybush wood without any mention of it. Their respective successes could be quite significant if marketed cleverly. ii Declaration “I, Francois Cillié, declare that this research report is my own, unaided work. It is submitted in partial fulfilment of the requirements for the diploma of Cape Wine Master to the Cape Wine Academy. It has not been submitted before for qualification or examination in this or any other educational organisation” Signed: ………………………………… at Stellenbosch. Francois Cillié, August 2016 iii Acknowledgements To God be the Glory for giving me the enthusiasm, persistence and self-discipline, without which I would not have been able to pursue this dream! I would like to acknowledge and thank the following people who were part of this journey. From winery owners to winemakers, experts in their relevant industries and academics, they are: Braak, Wim. Piekenierskloof Wines. Clarke, Jim. WOSA, USA. Du Toit, Prof Wessel. Oenology Department, University of Stellenbosch. Oertle, Ivan. Woolworths. Engelbrecht, Deon. Stellenbrau. Ethelston, Pete. Red Espresso. Grimbeek, Michelle. Cape Wine Academy. Grier, Jeff. Villiera Wines. Hua, Gilbert. Afrikano, Taiwan. Howell, Mark. Wine, Wood, Whatever. Joubert, Tania. Global brand manager, KWV. Kritzinger, Heidi. Kanonkop Wines. Mullins, Tamsin. Windermere Cider. Reyneke, Johan. Reyneke Wines. Roediger, Dr Andy. Roediger Agencies and CWM. Smith, Justin. Smith Wines, USA. Smith, Samarie. Free-lance journalist. Streicher, Anita. Morgenhof Wines. Strydom, Trevor. Audacia Wines. Van der Merwe, Nico. Saxenburg Wines. Van Niekerk, Michael. Audacia Wines. Vlok, Arnold. Red Dawn Wine Licensing (PTY) LTD Wolfaardt, René. Cape Natural Tea Products. Zuckerman, Simon. Berkmann Wine Cellars, UK. Sincere thanks also go to my family and friends for their continued encouragement and support to finish the journey which I started so many years ago; when I first arrived in Stellenbosch. iv TABLE OF CONTENTS ABSTRACT........................................................................................................................................ ii DECLARATION..................................................................................................................................iii ACKNOWLEDGEMENTS.................................................................................................................. iv LIST OF FIGURES.............................................................................................................................viii LIST OF TABLES............................................................................................................................... viii LIST OF GRAPHS............................................................................................................................. viii LIST OF ABBREVIATIONS................................................................................................................ix 1. INTRODUCTION............................................................................................................... 1 2. PRESERVATIVES AND ANTI-OXIDANTS IN WINE – CURRENT PRACTICE..... 3 2.1 A short history................................................................................................................. 3 2.2 Anti-oxidants and preservatives naturally present in grapes and wine............ 3 2.2.1 Acids.................................................................................................................................... 4 2.2.2 Alcohol................................................................................................................................. 4 2.2.3 Gasses................................................................................................................................. 5 2.2.3.1 Carbon dioxide..................................................................................................................... 5 2.2.3.2 Oxygen................................................................................................................................ 5 2.2.3.3 Sulphur................................................................................................................................ 5 2.2.4 Glutathione.......................................................................................................................... 5 2.2.5 Lees..................................................................................................................................... 6 2.2.6 Tannins................................................................................................................................ 6 2.3 Anti-oxidants and preservatives added to wine...................................................... 7 2.3.1 Acids.................................................................................................................................... 7 2.3.2 Alcohol................................................................................................................................. 8 2.3.3 Dimethyl dicarbonate........................................................................................................... 8 2.3.4 Gases.................................................................................................................................. 8 2.3.4.1 Argon................................................................................................................................... 8 2.3.4.2 Carbon dioxide..................................................................................................................... 9 2.3.4.3 Nitrogen............................................................................................................................... 9 2.3.4.4 Sulphur................................................................................................................................ 9 2.3.5 Glutathione.......................................................................................................................... 9 2.3.6 Natamycin............................................................................................................................ 9 2.3.7 Rooibos and honeybush wood............................................................................................ 9 2.3.8 Tannins...............................................................................................................................