Measuring Sugar Level

It is necessary to measure the sugar level of the juice you plan to make into wine. The initial sugar level may or may not be adequate to produce the alcohol level desired in the finished wine, and additional sugar may be needed. The percent sugar in the juice, for all practical purposes, is the degrees Brix. You need the following equipment to measure sugar level:

1. A hydrometer calibrated to read sugar levels from 0 to about 30°Brix (also called a sacchrometer).

(A hydrometer measures the specific gravity of a liquid on the Brix scale).

2. A graduated cylinder or a long glass tube in which to put the juice and the hydrometer.

3. A thermometer.

The procedure is as follows. Please note that hydrometers are calibrated to a particular temperature, usually 68°F. You must compensate for differences in temperature. A compensation table will probably be included with your hydrometer.

1. Fill the graduated cylinder or glass tube with your sample of juice. Make sure the juice is at room temperature (68°F) or make temperature corrections.

2. Insert the hydrometer and spin it by twisting the top of it. Wait for it to stabilize.

3. Read the sugar level in degrees Brix at the bottom of the meniscus or the "cup" at the top of the liquid level in the tube (drawing upper right).

A refractometer may be used to measure the sugar level instead of a hydrometer. A refractometer measures the amount the juice can bend light passing through it and translates the amount of refraction to the Brix scale at room temperature. The advantage of using a refractometer is that you do not require as much juice to read a sample as you do with a hydrometer. It is useful for a home grape grower who must determine when to harvest several cultivars of grapes and must process several samples prior to harvest.