Harvest (wine) of wine, winemakers would use the sugar and acid levels of the grape as a guide in determining ripeness. Early winemakers tasted the grapes to gauge ripeness. Modern winemakers use a refractometer to measure high sugar levels and °Brix or titration tests (using an indicator such as phenolphthalein) to determine the titratable acidity within the grape. In recent times there has been more of an emphasis on the "physiological" ripeness of the grape, usually in the form of tannins and other phenolics. Currently, tasting is the only way to measure tannin ripeness, which can take experience and skill to do
History of the wine press from olives. This press would entail laying the grapes out underneath several planks of wood and then weighing the planks down with rocks to press the juice out from the grapes. The wine made from these rudimentary pressing wasn't held in high esteem by the Greeks, often tainted with impurities and having a short shelf life. Much more prized was the wine produced from "free run" juice that was released by the grapes under their own weight before any treading or pressing. This wine was believed to be the most pure and was often used for medicinal purposes. In the