Since time immemorial grape harvesting has been a labor of love, weather and timing. In the northern hemisphere, typical harvesting times fall between August to October, but, like guessing a baby’s due date, grapes are ready for harvest on a schedule dependent on weather conditions, diseases and the very important detail of “ripeness” of the grape, which is measured by sugar content, acid levels and tannin.
These judgements about the readiness of the grape are made by the winemaker and vineyard owners. The harvest, no matter which month, is called “The Crush.”
Historically, grapes have been tested by taste. Winemakers and vineyard owners would sample grapes and determine whether they were ready for The Crush or whether they needed more time. A simple taste would indicate sweetness and acid levels.
Today, the taste is often replaced by a machine called a refractometer that tests sugar levels and a titration test for acidity. Neither tasting nor today’s modern machines can test for tannins. Tannins are a naturally occurring polyphenol that adds to the bitterness of the grape.
Grape harvesting is frequently done by hand – grape by grape. However, there are machines that can be deployed to The Crush. They operate by using rubber coated sticks to beat the vines until the grapes drop onto a conveyor belt.
The advantage is that they can operate 24 hours a day regardless of the heat. They can harvest up to 80 – 100 tons of grapes in a day compared to the 1-2 tons people can pick by hand. But like any machine process, the risk of damaging the grapes is higher with a machine harvest and it does not eliminate the need to look at the grapes before they are used for winemaking.
Sorting grapes is as important to winemaking as how and when they are picked. Beyond the obvious of sorting out grapes that are not ripe enough or that are rotten, grapes are also examined for damaged skins. This bruising on individual grapes can lead to discoloration of the wine. Tears in the grapes skin can cause grapes to oxidize and lose their aromatic properties.
Certainly, every winemaker looks forward to The Crush with huge excitement. It is the beginning of the crafting of every bottle of wine that will be corked for the year.
Big Creek Winery is preparing now for what we hope will be a successful harvest later this summer and in early fall. If you’re interested in seeing how some of these procedures are done, give us a call, and we’ll let you know when we’re get started on the The Crush.