fizzy kombucha, on purpose.
A starting point for kombucha after F1 (the first ferment), not a promise: F1 leaves sugar too, so if it still tastes sweet, use less. Check a tester; fridge the bottles when it's firm.
Ginger beer numbers come once my first batch is measured. The cheat sheet is kombucha math.
get the fizz cheat sheet1 page · ~400 KB · no email needed
how fizzy
is fizzy?
A unit brewers use for fizz is volumes of CO2: litres of gas dissolved in each litre of drink. Pick the number first, then dose the sugar for it. Each cell below is half a volume.
- cask ale 1–1.5 vol gentle
- british ale 1.5–2.2 vol soft
- lager 2.4–2.6 vol lively. my target
- cola 3.5–4 vol soda-sharp
- champagne 4.6–6 vol not in normal bottles
Typical values, rounded (UF/IFAS, Brew Your Own). Solid cells mark the low end of each range, outlined cells the rest of it.
no gauge? squeeze a tester.
- 1Fill one plastic soda bottle from the same batch.
- 2Squeeze it once a day.
- 3Hard to squeeze? Every bottle goes in the fridge.
Cold slows the build-up; it doesn't stop it. Keep the bottles cold once they're firm.
start with a kitchen scale.
You don't need a lab. Every recipe here works at level 0, with the numbers for anyone who has more.
- you own it
Level 0: Kitchen scale, your tongue, one squeeze bottle
Consistent sugar doses, and knowing when F2 (the bottle stage) is done.
- ~€10
Level 1: pH strips and a thermometer
A rough sourness check, and why warm batches run fast.
- ~€20–40 each
Level 2: pH meter and refractometer
Exact sourness, the reliable check before bottling, and a day-0 sugar reading. Recipes you can repeat.
- ~€15–25
Level 3: Gauge cap
Fizz as a number, and the fun experiments.
check before you bottle.
Kombucha F1 (the first, open ferment) must reach pH 4.2 or lower before bottling. Not there within 7 days? Throw it out. A calibrated pH meter is the reliable check.
Only bottles made for pressure: beer or soda swing-tops, PET soda bottles. Never jam jars, decorative glass or glazed ceramic. My limit in glass: 3.5 volumes, about 3 bar on a gauge at 20 °C.
Fuzzy, dry, coloured spots are mould: discard the batch and the culture.
Open bottles cold, over the sink, pointed away from faces.
a brewer's kitchen.
Five years of brewing beer. Now I'm bringing the brewer's tools to kombucha. Brewing right now: a kombucha, a jun (kombucha brewed with green tea and honey) and my first ginger bug. Every result posted, flops included.
- exp
- #001
- day
- –
- temp
- – °C
- pH
- –
- fizz
- – vol
- status
- fri 23.10
EXP #001, sugar vs honey with one bottle each, is finished. The result posts on Instagram on Friday 23 October, and its numbers land here after that: outlined while they're pilot data, solid once confirmed.
watch the experimentsthe fizz cheat sheet is free.
get the fizz cheat sheet1 page · ~400 KB · no email needed
Or comment FIZZ where a post offers the cheat sheet, and it lands in your DMs. Follow first, or check your message requests.