I am often asked when we pick or how we decide to pick, so I thought I'd post the answer. This is an extremely important process in determining the quality and character of the wine and we are very careful to get this just right.
Forecasting: First, we forecast ripening based upon tracking the number of degree days accumulated throughout the growing season. Using this data, which is based upon the mean temperture each day, we can create historical benchmarks that associate observed ripening progress to a number. Then we forecast when those numbers will occur in the current year to predict the ripening milestones such as bloom, veraison, and harvest.
Measuring: Once we have narrowed down the harvest window, we engage in statistcal sampling to assess the ripeness of a block of grapes. In order to get a valid sample, we must be careful not to select grapes from a single area, a consistent cluster position on the plant, or part of the cluster. Using some science from our day jobs, we actually perform the most laborious process possible, which is berry sampling. We go through and pick a single berry from lots of different clusters, careful to be varied (random) in our selection. After walking through the block, we have a bag full of berries. We hand-crush the berries into juice and then assess the juice for specific-gravity, pH, and titratable acidity. We also observe the color of the seeds and taste the juice (a reliable measurement the more experience you accumulate). Once all the numbers line up and the observations match our expectations, we're ready to go. Tools used for this process are a refractometer, a pH meter, an acid titration kit, and a hydrometer.
Forecast for this year is that we'll be picking later than usual and will start our measurements at the end of September, expecting to pick starting the beginning of October. -Jon-
Comments