In the vineyards at Cavender Creek and other sites across North Georgia, Véraison is nearly complete. This is the time when the grapes slowly turn from green through yellow and red to purple as they ripen. Irrespective of the color of the wine they create, almost all grape varieties follow this color change as they ripen.
With good weather and no big problems, it takes about a month from the end of véraison until the grapes are ready for harvesting. During this time, the tart green grape berries become less acidic and sugar levels increase (a process called sugar ripening). Simultaneously, the color of the grape and its flavors increase (this is called physiological ripening). The vineyard manager tastes the grapes and measures sugar level to assess ripeness.
The sugar content of the grapes is very important – it is this that will ferment to produce alcohol during winemaking. For grapes and their juice, this is usually measured using an optical instrument to obtain a reading called degrees Brix. Brix is actually a measure of the dissolved material in the juice – one degree Brix means 1% of the juice consists of dissolved matter. And since sugars are about 90% of the dissolved matter, this provides a measure of the amount of sugar in the juice.
1 degree Brix = 1% of the juice is dissolved matter = 18 grams per liter of sugar.
The ripening period presents its own problems. The changing color of the grapes attracts hungry predators like birds, mice and insects. And in Georgia we have other pests, like deer and even bears. Weather, especially rain, can also have a big impact. A little bit of rain may help to carry the process along. But too much rain can be bad – the grapes swell as the juice inside is diluted (which is bad for winemaking), reducing the quality. Rot can also set in, ruining the grapes.
At Cavender Creek, the fruit quality is looking good at véraison and we are hoping for a good harvest this year. Keep your fingers crossed for us that the weather hold fair and not too wet. If you are interested in participating in the seventh Cavender Creek harvest on September 17th, have a look at the Volunteer Harvesting event.