I derived this recipe from David Fankhauser: Making Ginger Ale at Home and the ginger bug in Katz, Sandor Ellix: Wild Fermentation. The Flavor, Nutrition, and Craft of Live-Culture Foods (Chelsea Green Publishing, 2003).

  • I replace the yeast used in the former with the latter, so that I get a wild starter.

  • I put in more sugar and ferment for several weeks, aiming for an alcohol content of around 5 % by volume. The detailed calculation is left as an exercise to the reader.

Ingredients for three 2 liter bottles

  • ca. 800 ml ginger bug (half that should also be fine)
  • 7 tbsp grated fresh ginger
  • 1 l cane sugar (900 g?)

Preparation

  1. Distribute the ingredients evenly on the three bottles (water helps) and fill up with cold water, leaving about 5 cm of headspace.
  2. Screw the caps on the bottles and do some inverting to aid the sugar in dissolving.
  3. Put the bottles in a not too cold place. After a day or two they should be quite hard. Carefully loosen the lid, so that gas comes out, but still maintain some pressure.
  4. Every few days, tighten the lid, invert the bottles and loosen the lid again.
  5. After some time (probably at least two weeks), screw the lid tight and let ferment until the bottles are quite hard. Put them in the fridge.
  6. Once they are properly cooled, the beer is ready for consumption. Be careful with opening.

Notes

  • It might be a good idea to use bottles which contained something sparkling before. Others might not be built to withstand high pressure.
  • In the winter months I found it quite useful to put the bottles on top of a radiator. – Cozy warmth speeds up the fermentation, but is by no means necessary. It would be a sin to turn on extra heating just to make this ginger beer.
  • If during the final fermentation not enough pressure is generated, you might add a teaspoon of sugar to each bottle and ferment for some more days.
  • When mixing the ginger-sugar-ginger bug mixture in the beginning, it might not be a good idea trying to dissolve all the sugar in the ginger bug. The osmotic pressure would kill the yeast.
  • I can't give a good total fermentation time, because it is very dependent on the environment and the mode of letting out gas. A carboy with airlock would probably be fastest.

Notes on the last batch

  • Started the last batch at 2014-02-28. Still fermenting.
  • Ginger bug had nearly died because of too much sugar. Saved it by halving and filling up with water.
  • Non-carbonated water bottles from Bilka are not so well-suited.