The winemaking philosophy of Coates Wines is not predicated on fashion or blind adherence to dogma, the processes we use (and avoid) have grown from experience and understanding. My training is as a winemaker (with a Masters Degree from the University of Adelaide), backed by Australian and International experience. Making wines from the large scale commercial end down to small batch boutique provides a pragmatic perspective on the wine world. Coates Wines are made in a way that is hoped will provide sensory delights truest to region and variety. Those who make their wines with a different philosophy to my own make different wines to my own. Experimentation and diversity is welcomed in the vinous landscape.
Natural Yeast Fermentation.Natural yeast/wild yeast/indigenous yeast. The process of using the natural yeast present in the vineyard and winery is fashionable and makes for great marketing. But why?
Current winemaking 101 mandates using freeze dried yeast of particular selected strains (hundreds are commercially available) to maximise fermentation efficiency and provide maximum flavour impact. The reasoning is strong for the production of large scale commercial wines, but for artisanal batches of wines I feel that wild yeast provides benefits.
- The fermentation kinetics are altered to provide a slower start to fermentation. Often natural yeast fermentation will be slower to start and finish, allowing for a longer time on skins under the protection of small amounts of carbon dioxide produced by yeast.
- A flavour profile develops that is less fruit intensive. Fruit intensity is something that winemakers strive for and many journalists spruik constantly. The Coates range is made with complexity and balance in mind; I prefer the flavour profile of natural yeast for the savoury accents that are provided. This can be seen to be mindful of a terroir driven approach to winemaking.
- One potential risk of natural yeast fermentation is the production of volatile acidity. Personal observation using natural yeast is that volatile acidity (acetic acid or vinegar–like aromas, and ethyl acetate or nail polish remover aromas) is greater that using cultured commercial yeast. The volatile acidity components are present in all wines; too much and the wine is compromised, whilst too little can remove yet another component that adds to the complexity and dynamics of the wine. In rare cases the level of volatile acidity, after increasing with ageing in barrel (a natural occurrence), can become borderline; those barrels are declassified out of the Coates range.
Avoiding Fining Agents and EnzymesThe list of winemaking fining agents and enzymes become longer every year. Those wineries that use these agents do so for sound commercial reasons. At Coates Wines the preferred approach is getting it right first time, or going the 'long way around' to avoid using fining agents and enzymes. Quick to make and fast to market. The science and application of fining agents and enzymes is complex, but a simple explanation of their use is -
- Hasten the winemaking process. Time is money, and enzymes can aid in clarification of juice post pressing or obtaining better red wine colour in a shorter time. Using egg whites, milk powder and gelatine on red or white wines can soften the tannins out and make for an earlier bottling date. Our wines just take more time to get to where we want them to be.
- Obtain better yield. Extraction rates (amount of wine made per tonne of grapes) can be increased with enzymes and fining agents, a better yield means a lower cost base. An increase in yield comes at the expense of another manipulation process performed that can detract from the inherent flavour and aroma of that wine.
- Correct mistakes. Too much tannin, not enough colour, too much colour, over extracted and too bitter? These issues can be fixed, and the resultant wine made to a higher quality. Again, this is another manipulation of the wine that can detract from the natural flavour and aroma profile. We try to avoid making mistakes and declassify our slip ups; no one is perfect and things do sometime go astray in wineries.
Filtering red wine acts primarily to achieve an aesthetic goal. As wine drinkers, we like our wine to appear bright and haze free. That clarity does come at a cost; it is another process that removes aroma and flavour from the wine. There is also a risk of filter material taint in the wine, and potential for water dilution and wine losses through the filtration procedure. Time and cost are two other considerations.
For a medium or large winery it makes sense to filter. The wines have a bright appearance which is requisite for their customers and those they supply to in wholesale such as supermarket chains. The use of sterile filtration is applied by many wineries. In this process the filtration is multistage to provide a level of filtration such that yeast and bacteria are removed from the wine. Their removal prevents any further microbial activity in the wine in bottle (Sulphur Dioxide also does this). Sterile filtration is especially important for wines that have residual sugar and a risk of refermenting once in bottle, and many white wines that have unfermented malic acid. Refermentation in bottle would be disastrous from an aesthetic viewpoint and the aroma and flavour aspect of the wine.
Our red wines are no longer filtered; even those exceptions in the past underwent only a light filtration. For most commercial wines the filtration process takes place firstly at the winery, and secondly during the bottling process (which can be up to three filtration stages in a row). To my way of thinking, that is two more steps that can potentially upset the wine and detract from quality. Time spent during maturation in barrel aids the settling of suspended materials, mostly yeast cells called lees. With minimal barrel handling the lees compact reasonably tightly at the bottom of the barrel. During racking (removal of the wine from the barrel) prior to bottling every care is made to maintain the best clarity in our wines by gentle handling and very slow pump speeds.
At bottling, our wines use a fine stainless steel mesh (screen) prior to the wine entering the bottling filler tank. The screen is only used as a precaution to keep any visible sized particles from going in to bottle. With time you may see a very fine deposit in Coates red wines, perhaps a very small price to pay for ensuring the best result makes its way into your glass.
To obtain the level of clarity expected in white wines we rarely filter. In most cases we achieve a very good level of clarity and brightness by gravity settling for the two weeks prior to bottling.
Tannin AdditionsCorrect balance of a red wines hinges on the interaction of fruit, oak, acidity, tannin and a small amount of residual sugar (less that 3 grams per litre remaining after fermentation). Getting the tannin contribution correct is not easy, and varies for variety, region and vintage. Tannins may be added for a few reasons –
- Hasten the production process. Tannin extraction comes with time during fermentation, large scale red wine production may allow as little as five days on skins prior to pressing. Our wines are left to ferment long enough to build an appropriate structure that suits the variety, region and vintage of the wines we produce.
- Provide structure to ordinary quality fruit. High yielding and/or poor quality fruit can be improved by tannin additions. Coates Wines is not making wines from those poor quality grapes.
- Bigger is better. Adding tannin can make a wine appear ‘bigger’ and with greater structure. A mouthful of aggressive tannin is seen as a plus by some wine drinkers. Machismo? Often the addition of tannins needs to be ameliorated by fining prior to bottling to make the wine palatable. In my winemaking view, that is two processes (adding tannin, and then fining some out again) that detract from the natural structure of the wine. The Coates range has natural tannins that contribute to structure through careful fermentation management. The tannins achieve balance and finesse through maturation time in barrel.
The WinemakerDuane Coates MW has a long held passion for Australian and overseas wines. He expanded his winemaking training with vintages in Burgundy with Chateau Demessey, the Rhone Valley with Domaine Francois Villard and the Douro Valley with the Fladgate Partnership (Taylor’s). Exposure to European wines and winemaking has given Duane a broad perspective on techniques and wines styles.
His spare time is spent with his partner and talented Chef, Rebecca Stubbs. Other passions include archery, Alfa Romeo cars, motorcycling and music.