Long time assistant Tyke Wheatley and Winemaker Mark Warren exchanging a word. Steam is emerging from the barrels due to the activity of a high pressure cleaner. Tyke now runs Windance winery. Mark, who clocked up his eleventh vintage for Happs in 2014 has his own label known simply as MARQ. See: http://marqwines.com.au/
The following may provide an insight into the way we approach the task of making wine.
1. Our approach to wine making
Wine making needs care and attention to detail. Ideally the fruit arrives still whole, its chilled prior to processing; the fruit has a full complement of amino acids to support fermentation, great colour and great flavour. We extract the juice with care, inoculate with selected yeast or alternatively wait for native yeast to get going according to the style desired, the ferment temperature is controlled, it goes quickly to dryness and we are off to a great start. But, it’s months or years before the wine is bottled and ‘what happens’ after fermentation is critical.
Louis Pasteur pointed out that wine is the result of arresting natural processes of degradation that begins with the action of yeast on sugar and stops at a point short of vinegar production. Vinegar is the work of aceto-bacteria (bacteria producing acetic acid from alcohol). These bacteria are present in wine at all times. They multiply and ferment when air is available. For this reason inert gas is reticulated to the headspace of all tanks and barrels are routinely topped. When a tank is incompletely filled we replace the air above the wine with carbon dioxide or nitrogen. We have an instrument to measure the oxygen content in the headspace and it is the most useful bit of apparatus that we possess.
Sulphur dioxide is a cheap and useful tool to control some bacteria that would otherwise interfere with yeast fermentation and leave a wine subject to spoilage. But used in excess or at the wrong time it destroys the wine. It will not control aceto-bacteria. Under the right conditions it is not essential. One can make wine without sulphur dioxide. In fact we make a red and a white wine each year without using sulphur dioxide. This exercise is an annual reminder of the requirements for safe natural winemaking. These requirements are described in the menu item ‘Preservative Free’.
At every step in winemaking one must be careful. Under what conditions will this wine ferment to dryness most safely and securely? Is this the right tank? Is this the right pump? How can I minimize the number of handlings that put the wine at risk of oxidation? When is oxygen beneficial? How can I bottle this product without air contact? How can I avoid damaging filtration? Is all fermentation complete or is there substrate remaining that will allow yeast or bacterial growth in the bottle? Is barrel storage appropriate for this wine? How old should the barrel be? Is the barrel clean? How do I store my dry barrels so that they stay fresh? Which are the right bottle and the right closure? Is my bottling equipment in good order?
An experienced winemaker can use finings to modify wine flavours or get out of jail in difficult circumstances, for example when the fruit is mouldy or partly spoiled. But, he cannot retrieve a wine that is spoiled by acetobacter, the yeast called brettanomyces or oxidation. These are faults that have their origin in fruit that won’t ferment properly or poor handling during winemaking.
A winemaker’s best tool is his nose and palate. It can tell him what is going on at the moment, the stage a wine has reached, something of its history and its possibilities. It tells him whether the product will be palatable and the value that he should put on the wine. However, a busy winemaker will maintain close contact with a good analytical laboratory and watch things like a hawk. He has to be diligent. Too often carelessness doesn’t show up until the wine has been in bottle for six months or a year. So, a good winemaker takes a look at the archives occasionally and owns his mistakes. A bit of humility doesn’t go astray. He is always limited by the quality of his raw material, the range of flavours that can be accessed and the extent to which he is supported in the marketplace.
2. The use of wood in wine making
At the outset let us realize that wine is acidic and corrodes metals. So wood has been used for centuries to make barrels to contain wine. Being circular the barrel rolls and is therefore easy to move and convenient for transport. Before the production of glass bottles, wine was drawn directly from wood. Concrete is rapidly corroded by wine and needs to be coated in epoxy paint or paraffin wax to protect the surface. The plastic liner of chateau cardboard is suitable only for short storage because it’s porous to air. Cheap stainless steel is a relatively new innovation.
Until very recent years the standard advice given in wine texts was to avoid contaminating ones best wines with the flavour of new wood. The solution was to rinse the barrel with steam or very hot water until wood stain ceased to discolour the water. The second step was to ‘condition’ the barrel with a lesser wine for a period before using it for ones superior product. Barrels were seen simply as containers and not as sources of flavour. There is good reason for this point of view. The wine in partly full or empty barrels is rapidly oxidised and spoilage bacteria multiply rapidly. Wood is a porous surface that is very difficult to clean effectively.
The availability of affordable stainless steel has meant a great deal to the wine and beer industries.
In 1997 we experimented with ‘stackvats’ – a cube like container with two wooden and four steel sides. This was a learning experience. The wood was not heated or steamed because it did not need to be bent to the curved shape of a barrel stave. The results were unattractive. Heating the wood is important determinant of the flavour that is imparted to the wine. However, the head of a barrel may not be heated by the cooper because it is not bent. We did a lot of work with small cubes of wood subjected to varying heating regimes in an electric pottery kiln then submerged these pieces in wine in a 375 ml bottle. Under these conditions oak pickup is fast. After trials we developed a preference for long heating (at least forty minutes), at just short of ignition temperature. The experience was instructive and led us quickly back to conventional barrels.
The modern wine industry seeks wood flavour in wine. In lesser wines the wood can make a more important contribution than the grape but the wine is not necessarily improved, despite the expense. In wines of class and real character the wood component, though considerable, may be barely perceptible. Only the grape accounts for palate sweetness and length in wine. The wood, and wood smoke, is capable of heightening and intensifying aromatic sensations which originate in the grape, but it is incapable of producing pleasant flavours in its own right. Married to grapes of quality, wood flavour is complementary. In the reverse situation its presence is all too obvious and the lack of desirable character in the grape equally apparent.
The choice of barrel size is important in that the ratio between wood surface area and wine volume depends on it. This then determines the ultimate flavour pick up. It also determines the rate of oxidative change due to absorption of air by the wine. Air is present in the pores of the wood on filling, and gains access via the less than perfect joints between the staves. If a barrel is equipped with a glass end and filled with water, one can observe minute bubbles of gas forming over the entire upper interior surface of the wood. Given the amount of air that is entrained as the wine evaporates, it is hard to imagine that the wine would survive storage in a wooden barrel. A rigorous topping regime is desirable to avoid ruinous oxidation. Regular checks of sulphur dioxide content are necessary, especially in warm climates. On the positive side, air supplied by a barrel quickly results in the clarification of young wines. One can observe the same effect in a plastic container because it too is permeable to oxygen. The effect of oxygen can be insidious. What looks good today when taken as a sample from a barrel can look rather more ordinary after a period of six to twelve months.
Raw wood characters, as one sees them in the aromatics of freshly sawn timber, are harsh and unattractive in wine. Barrels must be heated in order to bend the staves without cracking them and in the process the wood is to varying degrees cooked and smoked. Smoking adds inviting aromas to many foods apart from wine. The heating process changes greatly the compounds present in the wood, dries out the cells, shrinkage and weight loss are quite marked, and the flavours that are available wine change dramatically. Vigorous toasting at high temperatures can actually seal off the cells and delay, perhaps prevent, wine penetration into the wood. The tars present in wood, mobilized by heating, may be the sealing agents.
The flavours of wood charred to the point of ignition as seen in whisky are not as attractive in wine, as they add an acrid aromatic which may completely dominate. Thus, there’s a balance to be achieved between the flavours of unheated wood and those produced by extremes of heating. This balance is not easy to reach in all surfaces of a barrel because of the awkwardness of barrel shape and the location of the fire within the barrel. As noted earlier, the heads, which do not need to be bent, may not be heated at all.
Barrels from the same cooperage house produce variable flavours. Coopering practices are the major source of this variation rather than variations in the wood itself. Because the winemaker is not in a position to relate flavour differences to what a particular craftsman does, choosing appropriate barrel is a difficult affair.
The price of an imported wooden barrique of 227 litres capacity is in excess of $1350 per unit and their use is less and less justifiable as competition drives wine prices ever lower.
In a climate that is warmer than the locations in Europe, particularly in winter, there is a good argument to use larger barrels than the barrique of 227 litres that is used in France. However many winemakers prefer barriques because they are half the weight of a puncheon of 500 litres. Once committed it helps to standardise on one size. As an objective ‘convenience’ can compete with ‘excellence’.
When a young wine is put to wood it changes immediately for the better. One should not assume that the process is one way because, quite patently it’s not. More wood is not ‘more good’. This same comment is valid for all small containers. Putting wine in small containers is a bit like ‘playing with fire’.