The must meter is used to determine the amount (percentage) of sugar in the must. The meter works based on the density of the must.
Accurate measurement of the amount of sugar in the must is necessary when monitoring the ripeness of the grapes and determining the start of the harvest. Ten days before the scheduled harvest, we can start with the first measurements of the amount of sugar in the grapes. We collect 2-3 kg of grapes in different parts of the vineyard, squeeze the must, strain it through cheesecloth and measure the amount of sugar. This procedure must be repeated a few more times (every third day) and when the sugar content stops increasing, we can carry out the harvest. With the help of the meter and based on the amount of sugar in the must, we can predict the approximate volume fraction of alcohol in the wine.
Use: The must meter must be clean before use, residues of dried grape juice cause unrealistic measurements. Therefore, always clean and dry the must meter and measuring cup after use (wipe with a clean cloth).
Strain the must through cheesecloth, thereby removing impurities that affect the sugar level in the must. Pour the must sample into the measuring cup, cover the top of the measuring cup and mix the sample. Wait for the must to clear, grab the dry narrow part of the must meter with your hand and immerse it in the must (measuring cup). The meter must float freely in the liquid (it must not touch the bottom or the wall). Wait for the meter to settle - there must be no air bubbles on the walls of the meter.
In the attached table, read the measured value in Oechsle degrees (on a scale of 0 - 130) or as an approximate volume percentage of alcohol in the future wine (scale 6-15 vol.%). The must meter is tested at 20°C, which means that the measurement must be carried out at this temperature of the liquid. If the temperature of the liquid deviates from 20°C, correct the values read in the table.
