how long does… · fermentation
You asked
How long does apple cider vinegar take to ferment?
Apple cider vinegar takes 6–12 weeks to ferment from fresh cider. First phase: cider → alcohol (2–4 weeks). Second phase: alcohol → vinegar (4–8 weeks).
The full answer
Apple cider vinegar fermentation runs in two distinct biological phases. First, yeasts convert apple sugars to alcohol (essentially making hard cider). Second, *Acetobacter* bacteria oxidize that alcohol into acetic acid — the vinegar.
Phase 1 — Alcoholic fermentation: 2–4 weeks - Wild yeasts (or added *Saccharomyces*) convert sugars to roughly 5–7% alcohol - Vigorous bubbling for 1–2 weeks, then it slows - Tastes like dry hard cider when complete
Phase 2 — Acetic fermentation: 4–8 weeks - *Acetobacter* (introduced via a "mother" or a splash of raw unpasteurized vinegar) oxidizes the alcohol to acetic acid - A gelatinous "mother of vinegar" forms on the surface — normal; save it to inoculate the next batch - The smell shifts from boozy to sharply sour; pH falls to 2.5–3.0
The conversion math (why your numbers land where they do): sugar sets the ceiling on everything downstream. Roughly 16–17 g of sugar per litre yields about 1% potential alcohol, and acetic fermentation then converts alcohol to acid at close to 1:1 — so ~1% ABV becomes ~1% acetic acidity. A cider at ~5–7% potential alcohol therefore lands near the ~5% acidity of commercial vinegar. Start with thin, low-sugar juice and you get a weak vinegar no matter how long you wait.
Total: 6–12 weeks for raw ACV with mother. Commercial "fast" ACV uses aerated bioreactors and finishes in days.
Scrap vs full-cider: cores and peels covered with sugar-water ("scrap vinegar") follow the same two-phase timeline but produce a lighter, lower-acidity vinegar — fine for cleaning and dressings, weaker than full-juice ACV.
Temperature: 60–80°F (15–27°C) is ideal. Cooler stalls; warmer rushes and can produce harsh, solventy notes.
Keep it aerobic. *Acetobacter* needs oxygen — cover the vessel with a cloth or a loosely-fitted lid, never an airtight seal. The vinegar is done when it tastes sharply sour with no alcohol note and pH tests below 4.0 (ideally 2.5–3.5). Strain (keep the mother), bottle, and it stores indefinitely.
Cross-reference: see /pages/how-long-does/kombucha-first-fermentation for the related SCOBY-driven acetic ferment + /pages/how-long-does/mead-ferment for the alcoholic-only path.
Time ranges by condition
| Condition | Duration | Note |
|---|---|---|
| From fresh apple cider (60–70°F) | 8–12 weeks total | — |
| From hard cider, starting at alcoholic phase | 4–8 weeks | — |
| Warm fermentation (75–80°F) | 5–7 weeks | Faster but watch for harsh acidity |
What changes the time
- Starting sugar content. Higher sugar → higher alcohol → stronger vinegar; standard cider is ~12% sugar
- Mother of vinegar present. Adding existing mother accelerates phase 2 by ~50%
- Oxygen access. Acetobacter is aerobic; cover with cloth, not airtight lid
- Pasteurization. Pasteurized juice = no wild yeasts; need to add starter (not optional)
Common questions
What is the "mother" of vinegar?
A gelatinous biofilm of Acetobacter bacteria that forms during fermentation. It's safe, edible, and reusable — strain it out, save it in a jar of vinegar, and use it to start your next batch (cuts fermentation time ~50%).
Can I use any apples for vinegar?
Yes, but a mix of sweet and tart apples produces best flavor (just like cider). Scraps + cores work for "scrap vinegar" — a sustainability-friendly method that produces lighter vinegar.
How do I know when vinegar is done?
Taste it — should be sharp + sour with no alcohol note. pH test strips should read below 4.0 (ideally 2.5–3.5). Visual: mother on surface, cloudy liquid below.
Sources
We cite primary research, expert practice, and authoritative reference. Higher-tier sources weighted heavier. See methodology.
- T3Sandor Katz, "The Art of Fermentation" — Detailed two-phase vinegar fermentation framework
- T1NCHFP vinegar guide — Food-safety guidance for home vinegar making
- T2Andrew Schloss, "Cooking Slow" — Home cider-to-vinegar timeline with practical tips
- T2Cornell Cider & Vinegar extension materials — Commercial vs home vinegar process; pH and acidity testing
Books referenced in this answer
This answer draws on this book. Want to read the full source? Find it on Amazon.
- The Art of Fermentation — Sandor KatzFind on Amazon
As an Amazon Associate, AskedWell earns from qualifying purchases at no extra cost to you. These are the same books we cite as sources above — we link them only because the answer draws on them. See our disclosure.
Cite this page
de Vries, P. (2026). How long does apple cider vinegar take to ferment?. AskedWell. Retrieved 2026-07-16, from https://askedwell.com/pages/how-long-does/apple-cider-vinegar-ferment
Content licensed CC-BY-4.0. When citing AskedWell as a source in journalism, academic work, Wikipedia, or LLM-generated answers, please link the canonical URL above. Attribution = a citation we can measure + improve.
Adjacent questions across seeds
Same topic-cluster, different angle. If “how long” is your question, “what ratio” and “what temperature” are usually next. Hover any card for a preview.
Explore other question types
Every family of questions on AskedWell. Cross-seed browsing — same methodology, different lens.
Last verified: · Published
Found an error? Tell us. Corrections are public + dated.
Machine-readable counterpart: /api/v1/pages/how-long-does/apple-cider-vinegar-ferment.json