Almost all industrial ethyl alcohol sold in the United States is fermentation ethanol made from corn. Corn accounts for more than 95 percent of U.S. feed grain production and use, and ethanol production now consumes nearly 45 percent of the total U.S. corn crop, according to USDA’s Economic Research Service. The only meaningful alternative is synthetic ethanol, produced by the acid-catalyzed hydration of ethylene derived from petroleum or natural gas. Federal law does not distinguish between the two: 27 CFR 20.11 defines alcohol as ethyl alcohol “from whatever source or by whatever process produced.” So feedstock never appears on your TTB permit. It shows up instead in your impurity profile, your documentation package, and the questions your own customers ask you.
What is U.S. industrial ethanol actually made from?
Corn, overwhelmingly. U.S. farmers plant roughly 90 million acres a year, concentrated in the Heartland region from the Great Plains through Ohio, with Iowa and Illinois alone accounting for about a third of the crop. USDA ERS groups fuel ethanol under food, seed and industrial uses, which together make up close to 60 percent of domestic corn consumption.
Two different mill types sit behind that number, and the distinction matters more to a specification buyer than it first appears. Dry-grind plants mill whole corn, ferment the resulting mash, and produce distillers grains as the co-product; the large majority of corn entering U.S. ethanol plants is processed this way. Wet mills steep and fractionate the kernel first, separating starch, corn oil and gluten streams. Notably, ERS lists beverage alcohol and industrial alcohol among wet-milling outputs alongside fuel ethanol, which is a useful reminder that the plant behind your drum is not automatically the fuel-ethanol dry mill most people picture.
Grain ethanol vs. synthetic ethanol: the only real feedstock split
Everything else is a variation on process. The genuine fork in the road is biological versus petrochemical origin.
| Grain (fermentation) ethanol | Synthetic ethanol | |
|---|---|---|
| Feedstock | Corn starch; also sugarcane, wheat, sugar beet | Ethylene from petroleum or natural gas |
| Core reaction | Enzymatic hydrolysis then yeast fermentation | Acid-catalyzed hydration of ethylene |
| Typical trace impurities | Fusel oils, higher alcohols, esters, aldehydes from fermentation | Ethers, hydrocarbons, residues from the catalytic route |
| Co-products | Distillers grains, corn oil, corn gluten | None of agricultural value |
| Biobased carbon | Yes — demonstrable by radiocarbon testing | No — fossil carbon |
| U.S. industrial availability | Dominant | Limited |
| TTB treatment | Identical — both are “alcohol” under 27 CFR 20.11 | |
The impurity rows are where feedstock stops being trivia. Fermentation produces congeners; ethylene hydration leaves a different set of trace compounds. Both are polished to spec, but the residual fingerprint differs — and in fragrance, flavor and some pharmaceutical work that fingerprint is the whole argument.
How corn becomes 190 proof, and then 200 proof
Fermentation yields a beer of roughly 10 to 15 percent ethanol. Distillation concentrates it, but only to a hard physical limit: ethanol and water form an azeotrope at about 95.6 percent ethanol by weight, and no amount of additional rectification pushes past it. That ceiling is why 190 proof ethanol is the highest grade conventional distillation produces, and why it remains the workhorse for extraction, cleaning and most solvent duty.
Going above the azeotrope requires a different mechanism. Modern plants pass 190-proof vapor through 3A molecular sieve beds, which adsorb water preferentially on the basis of molecular size, yielding 200 proof ethanol specified at under 0.5 percent water. If you want the proof, percent and grade terminology laid out properly, we covered that in what ethanol purity actually means, and the practical trade-offs between the two grades in 190 proof vs 200 proof ethanol.
The important point for a sourcing conversation: dehydration is a purification step, not a feedstock step. A 200-proof drum and a 190-proof drum from the same plant started in the same corn.
Does the TTB care what your ethanol was made from?
No. TTB’s regulatory architecture is built around what the alcohol is and what you do with it, not what it grew in. Ethanol is produced at a distilled spirits plant qualified under 27 CFR Part 19. Denaturants are prescribed by formula in 27 CFR Part 21. Proof is defined by TTB as the ethyl alcohol content of a liquid at 60°F, stated as twice the percent of ethyl alcohol by volume. Feedstock appears in none of it.
Practically, switching from one corn-derived source to another has no permit consequence, and neither would switching to synthetic ethanol. Your paperwork is driven by grade and denaturant — whether you need an industrial alcohol user permit for specially denatured alcohol, or can buy completely denatured alcohol without one.
When feedstock genuinely does matter to your spec
- Trace impurity profile. Fermentation congeners and petrochemical residues are different problems. Fragrance, flavor and personal-care formulators frequently specify grain origin for exactly this reason.
- Biobased content claims. If you market a product on renewable content, you will eventually be asked to substantiate it. ASTM D6866 quantifies biobased carbon by carbon-14 to carbon-12 ratio — which cleanly separates grain ethanol from synthetic ethanol.
- Geographic origin is a documentation question, not an analytical one. This is the trap. ASTM D6866 explicitly does not determine geographical origin. Radiocarbon testing can prove your ethanol came from a plant, not that it came from Michigan corn. Origin claims live or die on supply-chain records.
- Identity-preserved, non-GMO, kosher and allergen programs. All of these are feedstock-and-records questions that a certificate of analysis alone will not answer.
- Supply continuity. Feedstock is the variable your lead times inherit. Corn basis, harvest timing and plant siting move availability well before they move price.
What to ask a supplier about feedstock and origin
- What grain is the ethanol fermented from, and where is it grown?
- Is the alcohol produced at a dry-grind or wet-mill facility?
- Can you supply lot-level traceability from the finished drum back to the production run?
- What is the certificate of analysis format, and does it report congeners or only proof and water?
- Are storage and transfer systems stainless, and what is the previous-cargo policy on inbound vessels?
- Is the feedstock consistent lot to lot, or does it vary with sourcing?
That last question is the one buyers most often skip and most often regret: a supplier who blends across origins can hit a proof spec perfectly while the impurity profile underneath it moves. Pristine Alcohol produces from 100% Michigan corn through 100% stainless steel systems at our Marysville, Michigan facility, which makes lot-to-lot consistency a documented fact rather than a hope.
Frequently asked questions
Is all ethanol made from corn?
No, but in the United States the overwhelming majority of industrial ethyl alcohol is corn-derived. Sugarcane dominates in Brazil, wheat and sugar beet are common in Europe, and a small volume of synthetic ethanol is made from ethylene. For U.S. buyers, corn-based grain ethanol is the practical default.
Can you tell grain ethanol from synthetic ethanol in the finished product?
Yes. Radiocarbon methods such as ASTM D6866 measure the ratio of carbon-14 to carbon-12 and distinguish biobased carbon from fossil carbon. What that test cannot do is establish geographic origin — the standard explicitly excludes it. Proving the corn was grown in a particular state requires supply-chain documentation, not laboratory analysis.
Does 200 proof ethanol come from a different feedstock than 190 proof?
No. Both typically start as the same fermented corn mash. The difference is a downstream dehydration step: 190 proof sits near the ethanol-water azeotrope at roughly 95.6 percent ethanol by weight, and 200 proof is produced by passing that stream through molecular sieve beds to remove the remaining water to under 0.5 percent.
Does the TTB require feedstock disclosure for industrial alcohol?
No. 27 CFR 20.11 defines alcohol as ethyl alcohol, ethanol or spirits of wine “from whatever source or by whatever process produced.” TTB regulates the plant under Part 19, the denaturant formula under Part 21, and your use of the material under Part 20 or Part 22. Feedstock is not a permitted or reported attribute.
Why do buyers ask for corn-origin or grain-origin ethanol if the regulations do not require it?
Because their own customers and certification programs require it. Non-GMO and identity-preserved programs, biobased content marketing, kosher certification, and fragrance and flavor house specs all reach past the proof number to the feedstock behind it. The regulatory floor and the commercial specification are two different documents.
Get a quote on bulk ethyl alcohol
Need grain ethanol with documented Michigan corn origin and lot-level traceability — in 192 proof beverage grade, 190 proof, 200 proof, or a denatured grade such as reagent alcohol? Request a quote or reach us through the contact page with your grade, volume and container format.