How to Use a Hydrometer

How to use a Hydrometer and what is Specific Gravity??

A hydrometer is simply a long glass cylinder with a weight at the bottom. It measures specific gravity (S.G.) or the weight of a liquid in relation to water. If you float a hydrometer in water, it will read 1.000 on the Specific Gravity scale. The hydrometer reading is accurate at 60 degrees F.

Most wine and beer hydrometers are "triple scale" with 3 useful scales.

1. Specific Gravity which measures the weight of the liquid.

2. Balling or Brix scale shows the sugar percentage by weight.

3. Potential Alcohol indicates the amount of sugar you start fermentation will yield the percentage of alcohol on the scale.

At the beginning of fermentation a typical reading might be 1.090. This means, for example, that the juice at that point weighs 9 percent more than water, or the juice is 9 percent thicker than water. When all the sugar is turned into alcohol, you will have a hydrometer reading on the Specific Gravity scale that is less than water - typically around .995. This means that the juice weighs less than water, or it is thinner than water by a half of a percent. Hydrometers are very simple to use and will help you gage your wines fermentation process.

How to use a hydrometer: put a sample of liquid in a test jar, hydrometer sleeve (if possible) or a wine thief. Place hydrometer into sample and at eye level read the figures on the stem of the hydrometer where the surface of the liquid cuts across the hyrdometer.