🍾 Speise Calculator
Carbonate your bottles the traditional way, without sugar: reserve a portion of your own wort (the Speise) before adding yeast, and use it to prime the bottles. Enter the gravity of that wort and the carbonation you want, and this calculator tells you how much to add per bottle.
Beer temp is the warmest the beer has been since fermentation finished: cold beer holds more CO₂ already, so it needs less Speise. Attenuation is the apparent attenuation of your yeast.
Compare amounts per bottle
Tip: fill a few bottles from the same batch with different amounts and mark them, to find the carbonation you like best.
| Speise per bottle | Final carbonation | Note |
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How to use it
- Reserve: After cooling the wort, and before adding the yeast, set aside 0 ml of wort and put it in the freezer until bottling day.
- Bottling day: Defrost the Speise in a pan, boil it for 5 minutes and cool it rapidly to about 25 °C.
- Dose: Use a measuring (medical) syringe to add 0 ml to each empty bottle, then fill the bottle as usual.
- Condition: Leave the bottles at room temperature for about 2 weeks.
Only bottle once the final gravity is stable (the same reading on several days in a row). If the beer is still fermenting, the leftover sugar adds to the Speise and the bottles can end up over-carbonated. These are estimates for a fully fermented beer: always test a few bottles first and use bottles that can take the pressure.
