Purpose: explain why the alcohol rule distinguishes source from percentage, and give you the chemistry to evaluate ingredients honestly instead of applying the limit mechanically.
Related: criterion 2 §4 (alcohol rule) · unit operations · detection & testing
1. How ethanol is made (fermentation)
Yeast (Saccharomyces and relatives) converts sugars to ethanol and CO₂:
glucose → 2 ethanol + 2 CO₂ (anaerobic glycolysis)
Practical yields mean a sugar solution can reach roughly 10–20% ethanol before yeast stops — which is why beverage alcohol is then concentrated by distillation (spirits) or left as-is (beer ~3–8%, wine ~9–15%, rice wine/sake, Chinese 白酒 is distilled to 30–60%+).
Key consequence for halal: ethanol is a normal biological product of any sugar fermentation. Foods that never had alcohol added can contain it naturally:
| Product | Typical ethanol range (varies by process) | Note |
|---|---|---|
| Soy sauce 酱油 (traditionally brewed) | ~1–3% | fermentation by-product |
| Bread / fermented dough | trace–~0.5% (mostly baked off) | crust retains less |
| Vinegar 醋 (double fermentation) | ~0.1–0.5% residual | see §4 |
| Yeast extract 酵母抽提物 | trace–low | by-product of yeast processing |
| Kefir / fermented dairy | trace–~1% | varies |
Ranges are indicative — always take the supplier’s CoA.
2. The two chemistries the rule distinguishes
(a) Ethanol formed in situ (fermentation by-product) — an unavoidable residue of making a permitted food. The Indonesian operational rule tolerates this within the ≤0.5% limit (max 0.49%) on the finished-product basis, provided the route is non-khamr and the product is not intoxicating.
(b) Ethanol deliberately added or derived from beverage alcohol — as a solvent/carrier/preservative in flavors, oleoresins, colors; or any product built from wine/beer/spirits (cooking wine 料酒, wine vinegar, “liquor-flavored” items). The rule: alcohol of khamr origin is haram at any level, regardless of the final percentage — even a 0.05% carry-over from a wine-based ingredient is haram. Non-khamr industrial ethanol (cane/molasses/cassava/maize, not made as a beverage) added to food is governed by the ≤0.5% tolerance — deliberately exceeding it is not acceptable even if the source is clean.
So the auditor’s question is never only “how much?” — it is “where did the ethanol come from, and was it formed or added?“
3. What “khamr source” means chemically
Khamr-adjacent products share one feature: the ethanol (or its vinegar/derivative) came from a beverage-alcohol route:
- wine, beer, spirits, rice wine 米酒, sake, 白酒, cooking wine 料酒 (wine + spices), wine vinegar 葡萄酒醋, red-wine reductions;
- ingredients extracted into beverage alcohol (e.g., vanilla steeped in wine);
- “liquor-flavored” confectionery or sauces (rum/茅台-flavored items).
Non-khamr ethanol typically arrives as food-grade industrial ethanol (食用酒精 from sugarcane/molasses/cassava/grain) — chemically identical, but never intended as a drink. Suppliers’ CoAs or declarations must say which.
4. Vinegar — the transformation question
Vinegar is a second fermentation: ethanol → acetic acid (by Acetobacter). Halal analysis splits by starting material:
- Grain/fruit vinegar not from alcoholic drinks (Chinese rice/ 醋, malt, cider vinegar from non-beverage juice) — acceptable route (residual ethanol within tolerance).
- Wine vinegar (from wine) — the feedstock was khamr. Fiqh schools differ on whether the transformation (istihalah) purifies it; your LPH’s fatwa basis decides (🔎). Under the strict Indonesian operational reading, wine vinegar is treated as khamr-derived and rejected.
Auditor habit: ask “vinegar from what?” — the Chinese label may just say 醋; the spec sheet names the feedstock.
5. Solvent-ethanol ingredients and dosage math
Flavors (食用香精), vanilla-type extracts, and oleoresins frequently carry 20–60% ethanol as solvent. The finished-product tolerance works only if you do the arithmetic:
finished ethanol % ≈ ingredient ethanol % × dosage fraction
Example: a flavor at 50% ethanol, used at 0.1% in the recipe → ≈0.05% finished. Within tolerance if the ethanol is non-khamr and source-declared. The same dosage of a wine-based flavor is haram regardless of the math (§2).
Audit probes:
- supplier CoA/declaration of ethanol source for every solvent-carrying ingredient;
- declared usage rate × solvent level → computed finished contribution, vs the ≤0.5% (max 0.49%) limit;
- finished-product alcohol testing as verification where risk justifies (see detection).
6. Fermentation media — the other animal/alcohol trap
Microbial ingredients (enzymes, organic acids, MSG-type amino acids, xanthan, flavors via fermentation) grow on media that may contain animal peptone (see primer 01 §5) and may produce ethanol as a by-product. For such materials the flowchart alone is insufficient — this is the scientific basis of the rule that fermentation-route materials need certificates (criterion 2 §2).
7. Audit takeaway — evidence implications
- Two questions per alcohol-possible item: (a) source — khamr route or industrial/non-khamr? (b) formed or added? Khamr-source at any level = reject; added non-khamr above tolerance = reject; formed by-product within tolerance = acceptable with documentation.
- Demand source declarations, not just percentages — a CoA showing “0.3%” is meaningless until you know the ethanol’s origin.
- Do the dosage math for solvent-ethanol ingredients and keep the calculation in the file.
- Vinegar, soy sauce, yeast extract, fermented seasonings: ask what the feedstock was, not just the residual level.
- When in doubt, treat as non-compliant and escalate to certificate/replacement — the burden is the supplier’s (criterion 2 §4).