The decision when to harvest the grapes is based on several factors. Most important is our own experience and knowledge of each vineyard. We also take into account the weather forecast for the forthcoming weeks. Finally, we constantly evaluate the taste of the grapes and will sample them regularly from around the beginning of September for their chemical composition.

34KB	To determine the chemical composition of the grapes we first take a representative sample from each vineyard. Every week we select 100-200 berries from each vineyard for analysis.
34KB 32KB 16KB	Then we press these berries and filter the juice With the juice we measure the density (°Brix), the titratable acidity (expressed as tartaric acid) and the pH.
23KB 15KB	The sugar content of the juice is measured by a Refractometer, an optical instrument. The acidity is measured by titration and the pH is measured using a pH meter.
31KB	For each vineyard a graph is drawn up. By interpreting the graph we can judge the current stage of ripeness and estimate the future development of the grapes. In the graph shown on the left it is apparent that the Brix and pH have increased significantly since the date of the previous sample. The significant rise in the pH value is not reflected in the value of the titratable acidity.