What is the function of a hydrometer in winemaking?

The function of a hydrometer in winemaking is to measure specific gravity and potential alcohol. This tool is essential for winemakers because it allows them to determine the density of the liquid, which can indicate how much sugar is present in the must or wine. As fermentation occurs, yeast converts sugar into alcohol, resulting in a change in specific gravity. By taking initial and later readings with the hydrometer, winemakers can calculate the potential alcohol content of the wine. This measurement is crucial for monitoring the fermentation process and ensuring the desired style and quality of the finished wine.

In contrast, measuring the acidity of wine is performed using a pH meter or titration methods, and barrel age is assessed through different means such as tasting or visual inspection. Testing for fermentation completeness typically involves evaluating the presence of residual sugars or using other analytical methods rather than solely relying on a hydrometer.