Sample collecting during harvest is a fundamental process before picking the grapes. We have already talked about it and explained the details of this task that is performed manually in the plots picking berries one by one, and identifying them accurately. Then, all of them come into the Laboratory, where they are thoroughly analysed, weighing them and checking the potential alcohol and acid levels. If the parameters are correct, we start harvesting the grapes in the plots, because we should collect the grapes only when they reach their optimal ripeness.
However, once the grapes are harvested, the last sampling is always performed before the unloading of the trailers. Nowadays, it has become a fundamental process, and we perform it in every batch of grapes that comes into Cuatro Rayas Winery. This procedure is possible thanks to the help of a mechanical arm, popularly known as the “sampler stick”.
This articulated arm is equipped with an endless screw that we introduce vertically into the load several times, to take a few grapes. Once the sampling is performed, it is introduced in a small vat, which in turn, goes through the refractometer. That is to say; we analyse again the parameters relating to the potential alcohol, pH, and acid levels so that it is a sufficiently representative sample of the entire load. Data are stored, but the last sample goes to the Laboratory, where is analysed with infra-red technology, to check other parameters as potassium, malic acid content and sanitary state (grey rot, acid rot), among others.