Thursday, January 27, 2011

Down Time??

Old wine bottles I've collected
 It may seem like there is a lot of down time in the winter, but the winery keeps me busy. This is the time when I blend wines to make a new product,

I'll blend many different wines and store them for later use, to make sure that the blend ages well. Some wines, when blended, taste great for a few days or even a couple of weeks; but over time I'll notice that the taste "turns away". I'll usually re-taste the wine about a week or so after the initial blend, and again after a few months, to make sure it is compatible for long storage times.
  "it a tough job, but somebody has to do it.  Its always a good idea to ask some friends over to help you judge the blends. Otherwise, you'll end up drinking all the resulting blend yourself (yipee!), either way its a great way to spend a snowy afternoon.
       Believe it or not, there is actually a scientific approach to blending wines - but don't worry, it's really rather simple. If you can add and subtract, I'll show you a method of blending that involves using a visual math tool known as the Pearson Square.

The easiest way to illustrate how the Pearson Square works is to do an example....
For our illustration, let's say I'm blending because I would like to lower the level of alcohol in the wine. I have some Merlot that is 15% alcohol, and I would like to blend it with another wine so that the new wine 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:

Pearson Square
The center of the square, shown by the letter "C", represents the "target" value I want to blend for (in this case, I 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 ( 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. 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:

Pearson Square - Example calculations
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?

I use this same sort of logic when I want to raise or lower pH, acidity, sugar levels, specific gravity. I just put the target value in the center, the known values for the two wines in the left corners, and do some subtraction to obtain the mixing ratios.

I only blend small quantities of wine until I achieve the desired effect. There is no need to make a lot of something that I'm not be pleased with. I only blend wines that were made in the same year. This will ensure that the new wine will last for a while.  I always keep detailed notes on my blending attempts so I can duplicate the blend in the future.

It's time to get back to work, the rowdy crow is yelling, "more wine, more wine!"
~ Old dog~


  1. Wow! Very high tech planning you have. Good luck on the blending. Hopefully I can make enough someday to try that. How large is your vineyard?

  2. Merlot seems to be a favorite among the people I know, so if you ever want some third party opinions we will gladly help you out. A very interesting article. I never heard of Pearsons Square. Thanks for the education. It's always nice to learn something new. Have a great day!