Ask Wine Wizard

Sensing Ripeness In Grapes


Ben Corral — Fremont, California asks,

I went up to the vineyard I will be getting this year’s grapes from, but I forgot my refractometer at home and didn’t realize until I was out in the vineyard (a.k.a. a long way from home). How do I tell if my grapes are ready to pick?

Hey, it happens to me too. But fear not, we’re going to impart some information that’ll give you the confidence to pick even if you don’t know the Brix number. Many winemakers like knowing a lot about the batch of grapes they’re going to be picking, from sugar level (Brix) to acidity (pH and total acidity or TA) to even more esoteric color and phenolic ripeness markers. Mind you, the latter are really only available to folks with serious lab budgets (a full panel of grape or juice analysis can cost into the hundreds of dollars) or to commercial winemakers with serious laboratory staff.What about the rest of us, who don’t have the time and money to spend or those of us that get to the vineyard and realize we forgot our trusty refractometer? Well, obviously one can pack the plastic bags to collect a representative berry sample of the vines they’re going to pick and then squish the berries up and measure them when you get home . . . as long as you didn’t forget the bags too.
Response by Alison Crowe.