Making White Wine: the full-bodied, wooded style
Based on material originally prepared by Rod Church for a Nanaimo Winemakers educational session in August 2004 and September 2005. Substantially revised for September 2010.
The style and the appropriate grapes
Chardonnay, especially the oaky, buttery kind, is the classic example of a full-bodied, wooded white wine. Making it is more like making a red wine than an aromatic white wine, such as Gewürztraminer. Compared to making an aromatic white wine, the full-bodied style involves:
Starting with riper grapes (Brix to 25), with the result that the finished wine has higher alcohol and less acid. Significant contact with oak, either through barrel fermentation or some other means, thus giving the wine more complex aromas and enhanced tannin levels. Deliberate introduction of a malolactic fermentation to further soften the wine.
Sur lie aging (aging on spent yeast cells) to develop more aromatic complexity and body. Finishing “dead dry” or almost so. These wines usually have a longer shelf life than aromatic white wines and they tend to develop aromatic and flavor complexity with age.
Besides Chardonnay, Semillon and Sauvignon Blanc (and their Bordeaux white blends) are often made in this style. This is not the New Zealand style Sauvignon Blanc, but the style Californians call fumé, as in Fume Blanc. Viognier can be made in this style, too, and so can many other white wines, including Pinot Blanc and Pinot Gris. About the only white grapes that are never made in this style are the Germanic whites like Riesling and Gewürztraminer.
The rest of this note explains the main steps in making this style of wine. It assumes you are starting with settled juice. To have the best chances of success, you should know the following about your juice: Brix or sugar level, TA and pH, and YAN (yeast available nitrogen).
1. Getting started: thawing, protecting and adjusting
If you have frozen juice, there is no advantage (as there is with crushed red grapes) to prolonging the thawing. Only bad things can happen with slowness. After the ice has softened, consider forcing the thawing with a hot water bath.
Before you start adjusting your juice, make sure it is adequately protected. These additions should precede anything else you do. If you are waiting for the juice to thaw, add them as soon as the you have about 60% liquid.
If it hasn’t been added already (wineries will usually have added it), add 50 ppm SO2, unless you know there was a fair amount of rot or botrytis in the grapes, in which case add add another 50 ppm. You can also add 0.1g/L Lysozyme after you give the SO2 a couple of hours to bind. Lysozyme is not necessary, but it is desirable unless you are confident that the grapes were very clean at harvest. If a ML fermentation starts too early, you risk a stuck fermentation. Adding this amount of Lysozyme now will not affect your ability to induce a ML fermentation later with the bacteria you want (not some wild variety). A teaspoon or so of pectic enzyme (or alternative) per pail. Adjusting acid and sugar
White wines always have higher acid levels than red wines. This is because red wines are fermented with skins and seeds and therefore have significantly higher tannin levels. Acid and tannin “fight” one another, and high acid in combination with high tannin make a wine almost undrinkable. But full-bodied whites do have some tannin from the oak and they therefore require lower acid levels than aromatic whites. Full-bodied whites also usually aim for higher alcohol and therefore you usually start with more sugar (Brix) and less acid.
The standard recommendations for starting a white wine with the full-bodied, wooded style in mind are:
TA: 7.5. Anything in the 7.0 to 8.0 range will work. If your juice is below 7.0, you should consider adding acid at the outset. If you acid is much above 8.0, you might reconsider your style and aim for a aromatic style instead. But you can take some acid out later if necessary.
pH: 3.3.-3.5. If your pH is above 3.5 you should add tartaric acid to drop it, even if this takes you above the recommended TA levels. You can reduce this tartaric acid later.
Sugar: SG 1.099 (23.7 Brix) to 1.104 (24.6 Brix).
Some makers of full-bodied wines (especially Chardonnay) will accept (even seek) very high sugar levels, partly for flavor and partly for alcohol. If you are going to add water to reduce the Brix, do it now (use acidulated water unless you also have high acid). If you are going to add sugar, calculate the amount now, but add it later (in solution), as the fermentation is winding down (this helps to prolong the fermentation and is supposed to enhance flavor and body).
2. Managing the fermentation
Choosing a yeast: Although you can use almost any yeast successfully for this style of wine, D-47 is probably the most commonly used, with CY3079 and D-254 also favored by some Chardonnay makers.
If you are fermenting a significant amount (say 200 lbs and up) of the same grape, there may be advantages to fermenting in smaller lots and using a different yeast on each one. Full-bodied white wines can benefit from the complexity that different yeasts can add to the wine. Give your yeast the proper start in life by rehydrating them properly, using Go-Ferm. Read more on “Rehydrating yeast.”
White wines are almost always fermented cooler than reds, but very low temperatures are not as important for full-bodied white wines as they are for aromatic white wines. The target fermentation temperature range is 15-20°C. (59 -68 degrees F). Some yeast work best in the 18-20°C range. These ferments will take about two weeks or less. The usual strategy is to get your must started at close to room temperature to allow the yeast population to build quickly, and then, after about 24 hours, to reduce the temperature down by whatever means possible. Fermentations produce quite a bit of heat, so you need to stay on top of your ferment if you want to keep the temperature below 20°C. For ways you can control the temperature, see the suggestions in “Home winemaking strategies for keeping ferments cool.”
Nutrition for your yeast
There is nothing unusual about your procedures here. Simply figure out at the outset how much Fermaid-K and DAP you are going to add, and then add it at the proper points (25% and 50% sugar conversion). For the details on this, see “Adding nitrogen to fermentations.” Once you understand the procedure, you can also use Wyngaard’s YAN calculator to help you figure out amounts.
3. Getting the oak flavor
Full-bodied whites wines usually get some oak treatment. This is especially true of Chardonnay, but is also common for Semillon and Sauvignon Blanc (in the Fumé style) and is sometimes used with Pinot Blanc, Viognier, and Pinot Gris
Fermenting in a new barrel
The preferred way to get oak flavors and effects into wine is to ferment it in a new French oak barrel (medium toast). A common practice among club members with a new barrel is to put two lots of white wine through it before converting the barrel to use with red wines. You can start your ferment outside the barrel if you want to make sure it is going properly, but put it into a new or white-wine-only barrel soon after. (Watch you don’t overfill; the fermentation needs room.)
With barrel fermentation, you can leave the wine in the barrel for the subsequent MLF and sur lie aging. With a new barrel one must be careful, however, not to pick up too much oak flavor. Once you have enough oak flavor, you can move the wine to carboys for additional sur lie aging. Wineries typically use a mix of newer and older barrels to ensure not too much oak flavor comes through.
Do not use a barrel for white wine after it has been used for red.
Using oak cubes
Rather than ferment in a barrel you can just add oak chips or cubes to your fermentation in carboys. This can work very well, and it can be almost impossible to tell the difference between this method and real barrel fermentation. Cubes are better than chips and French oak is usually considered more appropriate than American oak in terms of flavor. About 1g/L of oak cubes is about right.
NOTE: Don’t even consider the “liquid oak” you can find in some wine supply stores. It doesn’t produce results even close to taste of real wood.
Monitoring oak uptake
You need to monitor oak uptake in your wine. You want to make sure your wine does not get too oaky. You can’t get oak flavor back out of your wine. All you can do is dilute the effect with un-oaked wine.
You can add more oak later, especially during the ML-sur lies stage, but experience suggests that oak additions at this point produces flavors that are not as well integrated as the ones achieved during fermentation.
4. ML fermentation and sur lies development
Much of the key to the full-bodied white wine style come after the primary ferment. Rather than rushing the wine to the bottle as one does with aromatic white wines, there is a bulk aging process that involves two major components: the malolactic fermentation and sur lie aging.
To ensure you have a MLF, and the kind you want, you introduce ML bacteria into your white wine, just as you would with red wine. There are, however, a couple of special consideration with MLF in white wines.
Introduce your ML bacteria only at the end of the regular fermentation, when you bring the wine back up to room temperature. Some of the yeasts most favored for white wine do not like a concurrent MLF. Also, when ML bacteria are active in the presence of sugar, they act on the sugar rather than the malic acid, leading to an increase in “buttery” flavor and acetic acid (which is more noticeable in whites than reds).
Remember to bring your wine to room temperature. You will not get a decent MLF at temperature much below 20ºC.
Consider feeding your ML fermentation with nutrients, especially if you are not aging sur lie, (with aging on the lees, the spent yeast cells can provide the nutrients).
Make sure your MLF runs to completion. If possible, use chromatography to test for the completion of the MLF. See “Malolactic Chromatography Testing.”
IMPORTANT. As soon as the MLF is finished add the appropriate amount of SO2 for the pH level of your wine. The MLF has been producing CO2, which helps protect the wine, but with that phase over, SO2 protection is critical Sur lie aging can continue after you have added SO2. Consult the chart for the amount of 10% metabisulfite solution to add.
Sur lie aging
“Sur lie” is French for “on the lees,” but only the fine lees of spent yeast, not the gross lees or other organic matter. Aging on the lees is a practice than can be used with any wine (and increasingly is) but it is most commonly associated with full-bodied whites, especially, Chardonnay, Sauvignon Blanc and Semillon. Sur lie aging is often accompanied by malolactic fermentations. There are several advantages of sur lie aging:
Lees contact encourages the malolactic fermentation because it provides the micronutrients needed by the ML bacteria.
Lees contact is thought to contribute to a richer mouthfeel.
Lees contact can add some complexity to flavor. Fine champagnes develop yeasty, bready flavors after several years on the lees in the bottle. Normal full-bodied white wines are not aged on the lees anywhere close to that long (a few months to a year is the usual range), but the champagne-effect hints at what can happen to flavor with more limited lees contact.
How to do it:
Either carboy or barrel can be used. You want the lees to form a sediment an inch or so in depth. You can introduce fresh yeast if you do not have enough after racking your wine, but that can be expensive. Stir (what the French call bâtonnage) regularly (every one or two weeks). If you don’t, you run the risk, especially with a deeper sentiment, of producing H2S, mercaptans, or various other sulfides and disulfides. This happens when the yeast autolyse (digest themselves) in the absence of enough oxygen. The amino acids in yeast and other compounds in wines can be reduced to foul-smelling sulfur compounds. Make sure to stir gently. You do not want to introduce air into wine.
Along with stirring, taste and smell your wine. Don’t let the process go on too long.
5. Finishing the wine
Once you have developed the flavors and body you want from sur lie aging, it is time to finish and bottle the wine. There is not the same hurry as there is with aromatic white wines, and you can let the wine age in bulk a little longer after you have taken if off the lees. But, in general, it is better to let white wines age in the bottle. That way the flavors that develop are kept in the bottle (when aged in bulk, some flavor will later be lost in bottling). Also, the wine is better protected from oxidation.
Finishing your wine for bottling involves several steps.
Getting rid of dissolved CO2
This is less of a problem with this style of wine than it is with aromatic white wines, because the wine usually spends much more time aging in bulk. But it still something to monitor.
Fining for proteins—”warm stabilization”
If your wine has not cleared naturally soon after fermentation, you will want to fine before you filter. However, even if your wine seems perfectly clear, you should fine for proteins anyway. Proteins produce haze in wine only when they have had time to form longer chains. Protein haze is an aesthetic problem in all white wines.
If you are unsure whether your wine is going to be susceptible to protein haze, heat a sample to 80°C for 30 minutes. After cooling, look for signs of haziness. Fining for proteins is sometimes called “hot stabilization.”
Fining with bentonite works to remove proteins, and so do combination finings involving Kieselsol (Kiesolsol/Gelatin or Kiesolsol/Chitosan). You can find more information in the note “Identifying and preventing protein haze.” Actually, home winemakers can’t prevent protein haze because it it is impossible to know if most of the protein has been removed. But it is important to try. A bright clear appearance for a white wine is important.
All wines are supersaturated with potassium bitartrates at the end of fermentation, and over time crystals (“wine diamonds”) will form and precipitate. This is a problem in almost all wines, but particularly whites, where the results are so visible. Like haze, this is more an aesthetic issue than a wine quality issue, but careful winemakers take try to get the crystals to form and precipitate before bottling. This is done by “cold stabilization.”
The colder the temperature, the more quickly bitartrate crystals form and precipitate. The ideal is to get your wine below 0°C (32 degrees F)(commercial wineries aim for -4°C, and keep it there for at least two weeks. If you can’t get your wine this cold or keep it there, the process will take longer. (Given long enough, the crystal will even form and precipitate at room temperature, as they do in red wines.)
NOTE on the timing of fining and cold stabilizing. Large commercial wineries will usually cold stabilize before they fine for final clarity and proteins. And home winemakers can do this too. But it is probably more sensible to combine these two steps. First fine, and then immediately start your cold stabilization. Usually this will mean you will get a firm layer of bitartrate crystals on top of the loose debris from the fining. This makes it easy to rack off perfectly clear wine.
Balancing the wine
Wooded whites do not have the same balancing issues as aromatic whites. Wooded whites have lower acid levels and they are usually finished completely dry or almost so. At most one might add sugar to the 0.994 SG level, which should not be enough to require sorbate. You do not want to add sorbate to a wine which has been through MLF.
However, you might find the acid level a bit low for your taste. Bitterness on the finish of a wine can sometimes be eliminated by a modest acid addition. But you need to realize that the acid you add could very well fall out in large part as tartrate deposits once the wine is bottled. Your period of cold stabilization will have gone to waste.
6. Getting ready to bottle
Let’s assume you wine is now protected, fined, cold stabilized, and balanced. You now want to get it in the bottle as soon as possible. There are no advantages to waiting with the aromatic style. And it will still be several months in the bottle before the wine is drinking at its best, because it needs to get over the shock of bottling and have time to develop its fruity aroma more fully.
It is not necessary to filter wines, even white ones, but filtering will also certainly enhance the clarity and appearance of white wines and it may even improve the quality. If you do filter your white wine, do so carefully. All white wines must be handled much more carefully than reds because they do not have the tannin to protect them from oxidation. This is especially true of light-bodied, aromatic wines, which do not even have oak tannins.
You should probably also filter at room temperature. This will help in the release of CO2 and will limit the update of oxygen (oxygen dissolves more easily in wine at lower temperatures, just as CO2 does
Final SO2 additions
Let’s assume you put your filtered wine in carboys. The last step (say a day before bottling) is to add your final dose of SO2. Ideally, you will determine the existing SO2 level in your wine (using titrets) before make this final addition. Here are the steps:
Consult the chart of SO2 additions to determine how much 10% sulfite solution you need to add for your pH level. Add 5-10 ppm more than this, to take account of SO2 loss that will occur in the bottling process.
Wooded whites generally have a reasonably long shelf life. They may be a bit of a down cycle for a year or so, but they usually enter a new phase of taste and enjoyment after a few years. So it makes sense, if you are bottling many cases of the same wine, to consider adding more sulfite (an extra 10 ppm) to cases you will open later. If your wine is in multiple carboys, this is easy to do. There is no reason not to sulfite at several different levels (in increments of 10 ppm) depending on how long you expect to keep drinking the wine. You just need to keep track of the wine that has the high sulfite level and make sure you open these bottles later. (For example, with five cases, number them 1/5, 2/5, etc, so you know the order to use them.)
You can bottle one day (or less) after you have made your final sulfite addition (you are just waiting for the SO2 to dissipate evenly). Bottle at room temperature, taking care to minimize exposure to air. Try to store the bottle wine in conditions that are 15°C or cooler.
Johnson, Hugh, and James Halliday (1992). The Vintner’s Art: How Great Wines are Made. New York: Simon & Schuster. This book has separate chapters on light-bodied aromatic and and full-bodied wooded whites. Good reading and informative.
Martin, Jeff (2001). “Building Bigger Okanagan Chardonnays.” Home Winemaking and Beyond. Proceedings of the 5th Annual Vancouver Island Amateur Winemakers Association, pp. 16-24. A very desirable re-read for anyone making Chardonnay.