The ancient Greeks used to mix their wine with herbs, spices, and pine-tree resin. In medieval England it was considered an honor to be given both the wine and the water pitchers so you could mix your drink according to your own tastes. In modern-day France, winemakers at world-famous chateaux such as Margaux and La Fleve concoct carefully calculated blends of each year’s harvest to achieve the perfect Grand Crus.
Wine has been blended for centuries. It long has been known by winemakers and wine drinkers alike that combining the virtues of one wine with another wine (or with something non-wine altogether) can create a beverage that is better than the sum of its parts.
You can blend for complexity, to balance different sensory characteristics such as astringency or oakiness, or to increase or decrease characteristics such as acidity or alcohol content. It all depends on the wines you start with and what you’d like to do with them.
Before getting started, it’s wise to follow a few helpful hints. First, most winemakers will tell you that blending a sound wine with a faulty wine will produce faulty wine. Some folks think that mixing a stinky barrel that has been spoiled by hydrogen sulfide with one that has no bad qualities will yield a drinkable wine. In most cases, after blending the two the stink will still be perceptible and what you’ll be left with is two barrels of undrinkable wine.
Second, blending two or more wines can cause unforeseen instabilities or other imbalances. Wine is a complex chemical soup that exists in a constant state of delicate equilibrium. Two wines that appear to be stable and sound might, when mixed together, throw a horrid tartrate crystal precipitation or worse, suffer a protein instability and become cloudy. This occurs because each wine’s unique equilibrium (often pH dependent) is thrown off when mixed with the other.
Third, it is critical to do many small-volume trial runs, called bench tests, before you make your master blend. This allows you to discover which proportion best meets your winemaking goals and whether the trial blend you like best will be stable. These trial runs are the essence of the blending concept. There are no recipes for blending, and each blend is the result of careful experimentation and record-keeping.
Blending for Complexity
Let’s say you have three wines. Each has something to contribute, but not one is great on its own.
The Cabernet is a little vegetative, the Zinfandel is fruity but dull, and the Merlot has a very neutral aroma but a lot of body. You think that together they might make a great wine.
Well, there’s only one way to tell what that magic proportion might be. You have to assess each wine’s characteristics individually, think of possible combinations and then, using very small volumes (a few milliliters), make up mini-blends in small glass containers. Let these mini-blends marry for a period of three weeks; observe for any obvious instabilities such as tartrate precipitates, cloudiness, or off-odors; and then pick the one you like best. (See How to Do a Bench Test, page 48.)
Many wineries operate on this principle. They use whatever resources they happen to have to produce the best wine possible, which then becomes their “premium” blend. You can do the same with your wine. Just remember to keep good records and keep tasting until you find what you like.
Balancing Sensory Traits
Another blending technique involves trying to increase or decrease the presence of a certain sensory characteristic such as acidity, sweetness, bitterness, or astringency. Say that your Zinfandel was extremely astringent, the Cabernet was very sour, and your Merlot didn’t quite finish fermentation, so it had just a bit of residual sugar left over.
Using the bench-test technique you would experiment with different proportions of each of the wines in your samples. The Merlot’s residual sugar might mitigate a little of the acid in the Cab, while the astringency of the Zin might be played down by the relatively neutral Merlot.
When making your mini-blends keep in mind what kind of volumes you’re working with. It doesn’t make sense to make bench-test blends that are five parts Merlot to one part Zinfandel unless you just want to make a small volume of this blend or have a lot more Merlot than Zinfandel. And don’t forget to taste, taste, taste until you find the magic combination that works best for you.
If you commonly measure such qualities in your wine as total acidity (TA), ethanol content, and residual sugar content, these numbers will help you fine-tune your blending technique. These numbers have a linear relationship and are useful for blending with the help of another tool: the Pearson Square.
Say Wine A has 11 percent alcohol and Wine B has 14 percent. Your goal is to achieve a wine with 12 percent alcohol. How much of each wine should you blend?
You don’t have to do any complicated algebra; simply draw a square on a piece of paper. On the upper left-hand corner write in the alcohol percentage (11) for the wine of origin with the smallest percentage, which in this case is Wine A. On the bottom left-hand corner of the square, write in the percentage for the wine with the highest concentration of alcohol, in this case 14 (Wine B).
In the middle of the square, write in your desired concentration, which is 12. Now take a deep breath. This is the only math you have to do.
Subtract Wine A’s value (11) from the number in the middle (12). Write the answer (1) to the right of your square. Draw a line above it. Then subtract the number in the middle of the square (12) from Wine B’s value (14). The answer should be 2. Write this number on top on the line that you’ve just drawn over the number 1. And voila! You’ve just discovered that for your two wines to come together to make a wine of 12 percent alcohol, you must mix them in a ratio of 2:1, which means two parts Wine A (11 percent) to one part Wine B (14 percent).
This little trick also works for titratable acidity, sugar, and free sulfur dioxide. It doesn’t work with with pH or any other units that do not behave in a linear manner.
So now that you’ve got a few ideas about how you might want to go about blending your wines, go for it! Even if you’re a very small-scale kit winemaker, you can experiment with blending by making different kinds of five-gallon kits and adjusting your volumes accordingly. And for anyone blending at any volume, it’s important to test, taste, and use your imagination.
Alison Crowe is a graduate of the University of California, Davis, winemaking program and works in the university’s Department of Viticulture and Enology.
How to Do a Bench Test
Even though bench testing (so called because it’s often done in the winery lab, on the “lab bench” or counter) is seen as something that only commercial-scale wineries can do, home winemakers can scale down the process and see very comparable results.
Basically the concept is that you want to make small versions of possible “big batch” scenarios, let these mini-batches sit for three weeks to let flavors and aromas marry, and then smell, taste, and evaluate the resulting mini-blends to see which one you like best. Then apply the proportions that result in the best blend to the larger final blend.
• About 5 to 10 tall (volume of 50 to 100 milliliter) clean, clear glass containers that are all the same (available in natural-food stores and chemistry-supply catalogs)
• Lids to fit containers (plastic wrap and rubber bands will work in a pinch)
• Graduated cylinders or graduated pipettes (available through winemaking-supply retailers)
• A clean, well-lit workspace, preferably free of strong odors, loud noises, or other distractions
• Writing materials
• A dark, dry cupboard or other storage area
Assess the dominant characteristics and possible shortcomings, if any, of the wines you plan to use. Decide what you want to achieve in your blend. Something obvious may present itself, such as trying to blend out the over-oakiness in one wine.
Once you have assessed the situation, you’re ready to start assembling your mini-blends. Calculate the proportions you’ll use by working with the Pearson Square method (outlined on page 50, “Measurable Characteristics”), or use arbitrary proportions such as one-third of each of three wines.
Begin by measuring in different proportions of the wines using the graduated cylinder or pipettes to completely fill the volume of your container to eliminate headspace. This is important because you are dealing with very small volumes of wine. Any oxygen might damage the mini-blend and skew your evaluation of it.
This is where a bit of math might come in. If you’ve used the Pearson Square method to calculate the proportions to be used, you must convert that over to volume. A 2:1 ratio of Wine A to Wine B means that you will put in two-thirds Wine A to one-third Wine B. If your small container is a 100 milliliter (ml) volumetric flask, then you will combine 66.7 ml of Wine A with 33.3 ml of Wine B.
For each sample, label the container with a bit of tape and a letter or number, and record in your notebook which proportions correspond with each.
Cap or seal the containers tightly, mix by inverting gently, and then store in a cool, dry, dark place for three weeks to let the flavors and aromas marry.
In three weeks observe the aroma, color, flavor, astringency, bitterness, and body of all of the blends. Record your impressions in detail, labeling each set of tasting notes clearly with the blend number. Pick the top three and taste them again. Rank these three wines in order of preference, and pick the top mini-blend to be your guide when making the master blend.
After the blending stage, it is important to stabilize the entire blend, not just the two or more wines that comprise it. An instability in the new wine might result if this is not done after blending and before bottling.