Cook Vineyard Weekly Newsletter 8.29.11
The sparkling wine harvest has begun in Sonoma. The Pinot Noir and Chardonnay grapes used for sparkling wines are picked at a lower brix level. For the rest of us (still wines), we have a month to go or longer.
The refractometer is one of the most important tools of the trade this time of year.
This device reads gravity in brix (sugar content) by measuring the degree that light passed through the sample is bent.
A lot of vineyard owners, viticulturist and wine makers use this device to measure the ripening of the vineyard. Normally a vineyard will raise one to two brix per week depending on weather and irrigation.
There are many ways to take a sample, but this is our procedure.
Walk through the vineyard block that is going to be harvested at the same time. In the morning is best. Remove berries from the cluster with your eyes closed. (This is called blind sampling). Take berries from both sides of the row. We recommend 100 berries per sample placed in a container which allows them to be crushed into a juicy mixture. Place a few drops of the juice on the prism located on the refractometer. Look into the eyepiece and face towards the sun. There will be a horizontal blue shaded area. At the top of the shaded area there will be a number which is the measurement of brix for that sample.
We highly recommend buying a refractometer that is temperature compensated. If not, there is a table based on this correction.
Most wine grapes are picked between 24 and 27 brix depending on many other factors of ripening. These other factors like ph are normally performed in a laboratory prior to harvest. Due to the expense it is best to wait until the required brix level before performing the other test.
If anyone wants to visit us in the vineyards to learn more about the world of viticulture, Please call us at 707.490.8921. Also check our face book account Cook Vineyard Management under discussions for more information.
David Christopher Cook
Cook Vineyard Management
P.O. Box 1481
Sonoma, Ca. 95476