Degree Oechsle

Vintners measuring Oechsle degrees with the refractometer
View through the eyepiece of a handheld refractometer.

Degree Oechsle (abbreviated ° Oechsle or ° Oe ; after its inventor Ferdinand Oechsle ) is a unit of measurement for the must weight of the grape must , i.e. the unfermented grape juice .

The must weight is a measure of the proportion of dissolved substances (mostly sugar ) in grape must and thus an important quality criterion for wine . It is based on the density of the must and is measured with a must scale , a calibrated hydrometer .

Alternative measuring principles for the sugar content of the must are:

definition

The amount of the must weight in ° Oe is obtained from the density of the must and the density of the water, each measured at 20 ° C, using the formula: ${\ displaystyle n}$ ${\ displaystyle \ rho _ {\ text {M}}}$${\ displaystyle \ rho _ {\ text {W}}}$

${\ displaystyle n = 1000 \ cdot (\ rho _ {\ text {M}} - \ rho _ {\ text {W}}) \,}$

if the densities are given in kg per liter. The degrees Oechsle indicate by how many grams a liter of must weighs more than a liter of water.

Value ranges and interpretation

In general, the must weight of a middle year in Germany is between 70 and 80 ° Oechsle. The Oechsle value only gives a limited statement about the quality of the finished wine: particularly sweet grapes result in a wine with a particularly high alcohol content, but the taste also depends on many other factors, including the acidity .

The possible alcohol content of the fully fermented wine can be determined via the must weight, i.e. when the yeast cells have converted as much sugar into alcohol as they can (maximum about 18  % vol. , At a higher concentration they die). A must with 80 ° Oechsle results in a fully fermented wine with 84 grams of pure ethanol per liter, which corresponds to an alcohol content of 10.6% vol. Trockenbeerenauslesen can reach over 300 ° Oechsle - in the record summer of 2003 , a Trockenbeerenauslese measured 331 ° Oechsle.

In Germany there is an official "table for determining the natural alcohol content in percent by volume from the Oechsle grade":

° Oe % vol
40 4.4
41 4.5
42 4.7
43 4.8
44 5.0
45 5.2
46 5.3
47 5.5
48 5.6
49 5.8
50 5.9
51 6.1
52 6.3
53 6.4
54 6.6
55 6.7
56 6.9
57 7.0
58 7.2
59 7.3
° Oe % vol
60 7.5
61 7.7
62 7.8
63 8.0
64 8.1
65 8.3
66 8.4
67 8.6
68 8.8
69 8.9
70 9.1
71 9.2
72 9.4
73 9.5
74 9.7
75 9.8
76 10.0
77 10.2
78 10.3
79 10.5
° Oe % vol
80 10.6
81 10.8
82 10.9
83 11.1
84 11.3
85 11.4
86 11.6
87 11.7
88 11.9
89 12.0
90 12.2
91 12.4
92 12.5
93 12.7
94 12.8
95 13.0
96 13.1
97 13.3
98 13.4
99 13.6
° Oe % vol
100 13.8
101 13.9
102 14.1
103 14.2
104 14.4
105 14.5
106 14.7
107 14.8
108 15.0
109 15.2
110 15.3
111 15.5
112 15.6
113 15.8
114 15.9
115 16.1
116 16.3
117 16.4
118 16.6
119 16.7
° Oe % vol
120 16.9
121 17.0
122 17.2
123 17.3
124 17.5
125 17.7
126 17.8
127 18.0
128 18.1
129 18.3
130 18.4
131 18.6
132 18.8
133 18.9
134 19.1
135 19.2
136 19.4
137 19.5
138 19.7
139 19.8
° Oe % vol
140 20.0
141 20.2
142 20.3
143 20.5
144 20.6
145 20.8
146 20.9
147 21.1
148 21.3
149 21.4
150 21.5

International use

Different units are used internationally for the must weight, i.e. the sugar content of the juice: