Jun

Why this method

Jun is a kombucha-family ferment built on green tea and raw honey instead of black tea and white sugar, run by a dedicated jun SCOBY that is adapted to honey and to cooler temperatures. The chemistry is the same two-step relay as kombucha — yeast to ethanol, acetic-acid bacteria to acetic acid — but jun’s culture skews toward more lactobacilli and less acetobacter, so the result is lighter, faster, and a touch less sharp. Honey’s readily available sugars and micronutrients make jun ferment quickly and carbonate readily, earning it the “champagne of kombucha” nickname. The starter-acid safety rule is identical to kombucha’s.

Parameters

Parameter	Value
Tea	green tea, 5-7 g per liter (steep cooler, ~70-80°C, to avoid bitterness)
Sweetener	raw honey, 50-75 g per liter
Culture	dedicated jun SCOBY (not interchangeable with kombucha)
Starter (mature jun)	10-20% of total liquid volume
Starting pH (after starter)	below 4.5 (target 4.2 or lower)
F1 temperature	16-22°C / 60-72°F (cooler than kombucha)
F1 duration	4-7 days (faster than kombucha)
Finished pH	2.5-3.5
F2 (sealed)	1-3 days, then chill
Cold storage / arrest	2-4°C

Equipment

• Wide-mouth glass jar, breathable cloth and band
• A genuine jun SCOBY plus reserved mature jun starter
• Calibrated pH meter
• Pressure-rated swing-top bottles for F2

Method

Brew green honey-tea

Steep 5-7 g green tea per liter in water around 70-80°C (boiling water scorches green tea) for 2-3 min, remove the tea, and cool. Stir raw honey (50-75 g/L) into the cooled tea — adding honey hot drives off its aromatics and can stress the culture. Cool to under 30°C before culturing.

Acidify the start (safety step)

Add 10-20% mature jun starter, then the jun SCOBY. Confirm the start reads below pH 4.5 (target 4.2 or lower). This acid head-start is the primary hurdle against mold and pathogens.

F1 — cool, aerobic build

Cover with cloth and hold 16-22°C for 4-7 days. Jun likes it cooler than kombucha and finishes faster; begin tasting and measuring pH around day 4.

Confirm and reserve

When pH reaches 2.5-3.5 and the brew is pleasantly tart, reserve at least 10-20% as starter for the next batch before bottling.

F2 — flavor and carbonation

Bottle into sealed pressure-rated bottles with a little honey, fruit, or juice. Hold 1-3 days at room temperature — jun carbonates fast, so check sooner than you would kombucha — then refrigerate at 2-4°C.

Caution

The acid head-start is the safety control. Always begin below pH 4.5 with at least 10% mature, acidic jun starter; do not ferment without it. Confirm with a meter — taste is never a safety test. Discard any batch with fuzzy, raised, colored mold; a smooth new culture layer is normal (see Mold vs. Kahm).

Caution

Jun’s honey sugars carbonate quickly, so sealed F2 bottles can over-pressurize fast. Use pressure-rated bottles, burp daily, and refrigerate promptly once carbonated.

Note

Use a true jun SCOBY. A kombucha SCOBY dropped into honey-tea will struggle — the cultures are not interchangeable, and a stalled, weakly acidic brew is a safety risk, not just a flavor one. Like kombucha, finished jun carries a small amount of alcohol, usually below 0.5% ABV.

🫙 Kombucha method

🛡️ pH safety calculator

See also

• Kombucha — the warmer black-tea-and-sugar parent method
• Water kefir soda — another fast carbonated culture drink
• Acidity and pH — why pH, not taste, decides safety
• Time and temperature — why a cooler set point slows or speeds the build