# Fermentation

> Plan, evaluate, troubleshoot, and safety-gate home fermentation for vegetables, sauces, kombucha, brines, pH, salt, temperature, gas, spoilage, and storage.

- Skill: `jeremylongworth-source/fermentation` (Agent Skill, multi-file: 3 files)
- Install (CLI): `npx skillmds@latest add jeremylongworth-source/fermentation`
- Raw SKILL.md: https://api.skillmd.com/api/skills/jeremylongworth-source/fermentation/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- License: MIT
- Author: jeremylongworth-source (https://skillmd.com/u/jeremylongworth-source)
- Updated: 2026-09-09
- Page: https://skillmd.com/skills/jeremylongworth-source/fermentation

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# Fermentation

## Core Workflow

1. Identify the ferment type, food, recipe source, batch size, salt or sugar level, acid source, container, weight or airlock, temperature, time, and intended storage.
2. Run a safety preflight before optimizing flavor. Fermentation safety depends on tested proportions, acidity, salt, temperature, oxygen exposure, sanitation, and storage.
3. Separate active fermentation from shelf-stable preservation. Do not imply room-temperature storage or canning is safe without a tested process.
4. Identify the state gap: brine coverage, salt concentration, acidification, gas pressure, mold or scum, texture, aroma, pH, or time-temperature history.
5. Recommend conservative controls, monitoring, and discard decisions when safety facts are missing or spoilage signs appear.
6. Lead with the decision or next action, then give only the mechanism details that change that decision.

## Fermentation Guidance

Use current authoritative preservation guidance for exact salt, acidity, pH, temperature, processing, and storage claims. Do not invent fermentation ratios or canning processes from memory.

For vegetable ferments, treat salt and brine as safety and texture controls, not only seasoning. Do not recommend reducing required salt in sauerkraut or fermented-pickle recipes unless a tested recipe specifically allows it.

For active ferments with normal cues, do not collapse every cloudy, bubbling, or sour-smelling batch into a discard decision. First separate expected lactic fermentation signs from mold, slime, unpleasant odors, failed acidification, poor submersion, excessive heat, or unknown process history.

For kombucha and other gas-producing ferments, include container pressure and refrigeration controls. Sealed bottles can become a physical hazard when carbonation is not monitored.

For sourdough starters, separate culture strength from contamination. Weak rise, slow bubbling, or hooch usually call for feeding, temperature, timing, hydration, or flour adjustments; mold, unusual discoloration, or clear contamination calls for discard.

Route to `food-safety` for all home fermentation, canning, shelf-stable storage, reduced-salt adaptations, visible mold, soft or slimy texture, off odors, swollen lids, gas pressure, vulnerable diners, raw animal products, or uncertain time-temperature history.

## Output Contract

- Ferment type and user goal
- Safety gate and missing safety facts
- Recipe/source confidence
- Current state and target state
- Mechanism: salt, acid, microbes, temperature, oxygen, time, pressure, or storage
- Controls for brine, vessel, weight, temperature, monitoring, and storage
- Discard or escalation decision when needed
- Verification cues and source-check note for precise safety claims

## References

- Read `references/fermentation-checklist.md` when planning, adapting, troubleshooting, storing, or safety-reviewing fermented foods or beverages.