Fermentation, Non-Alcoholic Recipes, Techniques and Methods
Low-alcohol ferments add a lactic sourness and a natural sparkle that can replace fruit mixers, tonic water or ginger beer. Cleanliness is the one rule that must not be broken.
At a glance
Low-alcohol ferments add a lactic sourness and a natural sparkle that can replace fruit mixers, tonic water or ginger beer. The article introduces the family of ferments, from ginger beer and kvas to kefir and kombucha, and the one rule that must not be broken: cleanliness.
The fermented tonics in the world’s best bars come from many cultures and materials. Baker’s-yeast ferments give ginger beer and root beer. Fruit-juice ferments include tepache and aluá from Central America, sweet potato and cassava ferments come from South America, and kvas is the bread-based ferment of Russia. Kefir uses a culture that looks like white clumped balls, and kombucha is sweetened tea fermented with a gelatinous disc, a SCOBY, a symbiotic culture of bacteria and yeast. All share a balance of sweet and sour, a slight fizz and a reputation for health, but each makes a different drink.
In cocktails a ferment can take the place of a fruit mixer and add lactic sourness that goes with fresh, herbal and grassy flavours, or it can replace tonic or ginger beer in a highball, or it can be drunk alone.
Perhaps the most important rule of fermentation is cleanliness. You are creating ideal conditions for microbes, so the ones that grow should be the ones you intended. Boiling water and sterilising tablets are the tools, and the same treatment applies to every utensil. It matters most for pure yeast ferments, where bacteria will ruin the batch. Kombucha and kefir are more forgiving because the large bacterial culture you add protects the liquid.
Keep the ferment warm, at 20 to 24 C, and out of daylight, since UV light kills yeast and bacteria cells. Time depends on temperature, so a kombucha that takes weeks in winter may take days in summer. A pure yeast ferment works best closed, because limited oxygen makes the yeast more efficient, but fermentation produces CO2, so small batches use a cheap airlock valve on the bucket, carboy, demijohn or barrel to avoid a pressure build-up and explosion. Brewer’s yeast is usually fine, and a yeast strain from beer or wine, such as Champagne yeast, steers flavour, fizz and strength in that direction. Kefir and kombucha do not need to avoid oxygen, since the aim is sourness and bite; the author makes them in 2-litre wide-mouthed jars covered with cloth and a rubber band.
Before bottled CO2, all fizzy drinks were carbonated by fermentation. If a ferment still has unfermented sugar and is put into a sealed bottle, the yeast keeps producing CO2 and, with nowhere to go, it dissolves in the drink. A few hours or a couple of days may be enough. The ferment must then go in the fridge to stop the yeast before the bottle explodes. Adding a little sugar at bottling, called priming, gives the yeast more to work with. Too short, and the drink lacks fizz and is too sweet; too long, and it risks an explosion or foams over and is not sweet enough. Stephenson bottles part of each batch in plastic bottles with screw caps, which give a feel for the pressure when squeezed, and the rest in glass for presentation.
The Assam Kombucha of the Fermen-Tea Punch, the Ribinger Ferment of the Lobelia and the Banana Barrel Ginger Wine of the Banana Barrel Whisky Mac all come from this tradition.
In the author's words
Perhaps the most important rule of fermentation is cleanliness.
Page 43
Where this comes from
Written for this guide from the Fermentation chapter of The Curious Bartender Volume 2 by Tristan Stephenson (pages 43 to 44); the facts and the advice are the author's, the wording is ours, and the quotation is given with its page.
Keep reading
Techniques and Methods
A stirred drink is pure chilling and dilution, and consistency is the whole game. Dave Arnold covers the right ice, why metal beats glass, when to serve up or on the rocks and why colder is not always better.
Ingredients and Sourcing
Eight drinks without alcohol that rely on tea, fresh fruit, ginger, coriander and spice syrups for flavour and for a sense of wellbeing.
History and Culture
Wine-based drinks are among the oldest mixed drinks: the Champagne Cocktail, the Sherry Cobbler, sangria and the Americano all have well-recorded beginnings.
