Tuesday, October 31, 2006
For our illustration, let's say we are blending because we would like to lower the level of alcohol in our wine. We have some Merlot that is 15% alcohol, and we would like to blend it with another wine so we end up with a target alcohol of 12%. The other wine's alcoholic content is 11%.
Let's begin by showing you what the Pearson Square looks like. See the figure below:
The center of the square, shown by the letter "C", represents the "target" value we want to blend for (in this case, we want to obtain a wine of 12% alcohol).
The upper left corner, shown by the letter "A", represents the known alcohol percentage of wine #1 (Our Merlot, which is 15%).
The lower left corner, shown by the letter "D", represents the known alcohol percentage of wine #2 (another Merlot, which is 11%)
To use the Pearson Square, we merely substitute numbers for the letters in the diagram, and then do some simple subtraction. We find the difference between the values in the corner and the center "target" value, and place the answer in the opposite corners. This value is always the absolute value (no negative numbers allowed!) of the difference.... so, for our example:
15 minus 12 equals 3, and
12 minus 11 equals 1
Here's what the Pearson Square looks like now:
Voila! As you can see, we need 3 parts of the 11% wine to mix with 1 part of the 15% wine, and we will end up with our "target" wine of 12%. Pretty neat, huh?
There are other things to consider when blending wines. Such as, not blending a bad wine with a good wine, balancing tannins etc. The following links make great reads for exploring more about blending.
Blending Wines: Grapestompers
Blending Batches - Tips from the Pros: Winemaker Magazine
Blending to Improve Wines: Winemaker Magazine