Normalizovaný muštomer

A Mostwaage or Oechsle scale is a device for determining the Most weight, so the density of grape must. The Mostwaage is also used in the juice and fruit wine making from other fruits. Basically it is a countersunk screw or scale ( hydrometer ) with adapted scale division.

Barometers for determining the quality of the must used for over 300 years, but they were provided only in the 1820s by the Pforzheimer mechanic Ferdinand Oechsle with a practical scale, named after him Oechsle scale. This is common, especially in Germany, Switzerland and Luxembourg.

Oechsles invention is based on the finding that sugar is heavier than water. So he went out at the graduation of its scale on the specific weight of water: Does the Most the spec. Weight 1.075, the Oechsle scale displays 75 degrees Oechsle. The Ochsle scale used as the zero point, the density of water at 20 ° C ( rounded 1 g · cm -3). Most deviates the temperature of the reference temperature 20 ° C., a correction must be made of the indicated value. In Most scales with integrated thermometer to be added or subtracted value is displayed directly. Otherwise you can work at low temperature deviations with the following approximation:

• At temperatures above 20 ° C per 3.5 ° C per 1 ° Oe added
• At temperatures below 20 ° C per 3.5 ° C per 1 ° Oe is subtracted

Since the Ochsle scale used as the zero point, the density of water, it shows not only the content of sugar, but the content of all dissolved substances, the so-called total extract, to the juice. In order to determine the sugar content of the must, the content of sugar-free extract in the must be known. Since the determination of the sugar- free extract only upon laboratory equipment is possible to exist for the practice table values ​​for many fruit species in their application by year fluctuations are taken into account. Since alcohol at the same ambient conditions has a lower density than water, the Ochsle - balance can show negative values ​​in dry wines and fruit wines depending on Alcohol and Sugar free extract. In carbon dioxide-containing fluids such as wine fermenting the Oechsle scale displays no meaningful values ​​. Carbon dioxide must be extracted before the measurement.

In Austria, is measured by the Klosterneuburger (KMW ), where 1 ° KMW ( Klosterneuburg sugar levels ) corresponds to 4.86 ° Oe. Unlike the Oechsle scale of the putative sugar-free extract content of grape must is deducted from the outset, which is why the Klosterneuburger has a different origin than the Oechsle scale.