Grape berry sampling begins

July 26, 2018 by Marilyn Odneal

Karly and Makayla sampled berries from the grapes that were undergoing veraison. They then processed the juice from the berries and analyzed them for TSS, pH and TA.

After the berries were collected in the field, they are crushed in the stomacher to extract the juice.

After stomaching, the juice is poured off into a large beaker.

After the juice samples are centrifuged, they are strained before the analysis. We test two samples from each cultivar/vineyard combination.

The first test we run is degrees Brix or Total Soluble Solids that measures the sugar level in the grapes.

Our refractometer has a digital readout.

The pH of the juice is then recorded.

Lastly an acid-base titration is done to see the % acidity in the sample.