In Sonoma, the harvest is already well underway for sparkling wines and some Pinots. But for the deeper darker reds, we are just starting to do field sampling of berries. And beginning to forecast the harvest schedule. This is vital because every winery has a different style of wine and elects to harvest using different benchmarks. In addition, there is necessarily a lot of planning to assure that manpower is ready to go, tractors and picking bins are in place, and the winery is ready with open tanks for fruit delivery. Thus we start forecasting way in advance…
Below is a quick review of some fruit conditions around Kenwood and Bennett Valley as of Saturday am, August 26th, 2017:
Above is some nicely ripening Syrah, this one is the Bien Nacido clone (historically emanating from the Santa Maria Valley, and notably used by Qupe’ and Au Bon Climat).
This is a typical hand held field refractometer. With a few drops of raw grape juice on the window (the blue glass), the light is ‘refracted’ through the viewfinder indicating the percent dissolved solids, which is essentially a proxy for total sugar, i.e. ‘brix.’
This is a view through a hand held field refractometer.
And you can see this Syrah sample shows brix at about 21 (the intersection of blue and white), resulting in about 10.5% alcohol (if harvested today). Naturally, we are monitoring ripeness looking for closer to 24.7 brix and closer to 13% alcohol (although ultimately in very fine wines, such as ours, seed ripeness, tannins, pH, TA, and many other inputs will be considered before the harvest)
Here is some slightly less ripe Syrah, with equally sized berries but smaller clusters, this being the Durell clone (from the famous Durell Vineyard of the 1970’s in Sonoma).
And the brix are lower, hovering closer to 19.
With the Syrahs above, we simultaneously pick and co-ferment about four percent Viognier, seen here. Both Syrah and Viognier originate from the Rhone Valley in France.
On average, and very roughly depending on variety, clone, rootstock, day and night temps, wind, etc, clusters will gain about 1.5 brix per week. Thus a sample at 19 today, with a goal of 25 at harvest is about 4 weeks away…