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Sulphur Dioxide (SO2) additions using Potassium Metabisulphite

by Charles Plant

This table gives the volume in mL of 10% potassium metabisulphite solution needed to add a desired amount of sulphur dioxide to a known volume of must or wine.

Using the Table

  1. Locate the volume of wine or juice you want to treat (across the top of the table in the red or green rows).
  2. Locate the desired ppm of SO2 you require (down the left side in orange text.)
  3. The intersecting cell of this row and column displays the correct amount of 10% solution to add.
Your volume
in Litres:		 .75 1.0 4.55 19.1 22.7 25.9 27.3 54.0 114 150 182 227
Your volume
in Imp. Gallons:		 .17 .22 1.0 4.2 5.0 5.7 6.0 11.9 25 33 40 50
Parts per million
of desired S02:		 Millilitres of 10% potassium metabisulphite solution to add:
10 0.13 0.18 0.80 3.35 3.99 4.55 4.78 9.47 19.9 26.3 31.9 39.9
20 0.26 0.35 1.59 6.70 7.97 9.09 9.57 18.9 39.9 52.6 63.8 79.7
30 0.39 0.53 2.39 10.0 12.0 13.6 14.4 28.4 59.8 78.9 95.7 120
40 0.53 0.70 3.19 13.4 15.9 18.2 19.1 37.9 79.7 105 128 159
50 0.66 0.88 3.99 16.7 19.9 22.7 23.9 47.4 100 132 159 199
60 0.79 1.05 4.78 20.1 23.9 27.3 28.7 56.8 120 158 191 239
70 0.92 1.23 5.58 23.4 27.9 31.8 33.5 66.3 140 184 223 279
80 1.05 1.40 6.38 26.8 31.9 36.4 38.3 75.8 159 211 255 319
90 1.18 1.58 7.18 30.1 35.9 40.9 43.1 85.3 179 237 287 359
100 1.32 1.75 7.97 33.5 39.9 45.5 47.8 94.7 199 263 319 399
*Figures are based on 4.545 L/imperial gallon & 10% "Sulphite solution" being 5.7% available SO2 in mg/L

Preparing a 10% Potassium Metabisulphite Solution

The solution is made by adding sufficient water to 100 grams of Potassium Metabisulphite to bring the total volume to precisely 1 Litre. Store this solution in a tightly sealed clean glass container.

Determining SO2 requirements

If you're new to winemaking, or don't yet understand how to determine your requirements, the following figures can be used as a loose rule of thumb.

For bulk aging

  • Red wines: 20-30 ppm.
  • Dry white wines: 30-40 ppm.
  • Sweet white wines: 80-100 ppm.

At bottling

  • Red wines: 10-20 ppm.
  • Dry white wines: 20-30 ppm.
  • Sweet white wines: 50-60 ppm.