Method 3: The SEBAmyl Two-Rest
Working notes from real 2018 sessions, not a validated homebrew protocol — values are starting points, and the scale-translation warnings apply to all four methods.
Where this comes from: 2018 Robobrew session notes
This is one of four mash methods Bard's documented in 2018 while adapting its production process to homebrew scale, run on a Robobrew — a recirculating single-vessel electric system (why that equipment class matters).
Sorghum starch gelatinizes across 154–178°F, and this method’s 163.4°F rest opens only the lower part of that range. Plan for reduced extract, or add a gelatinization step — a boil or a hotter liquefaction — before you rely on this for a target gravity. Why, in full, below.
Why 163.4°F leaves starch behind, and what it costs you
Sorghum starch gelatinizes across 154–178°F (68–81°C) — a range, not a threshold. A rest held at 163.4°F opens the lower part of that distribution and leaves the rest intact, and intact starch is extract you paid for and will not collect.
The hundred-minute hold does not buy it back. Long holds help granules sitting near the threshold; starch whose gelatinization temperature is above your rest temperature will not gelatinize at any duration. That is a physical limit, not a patience problem.
The enzyme is not what is stopping you. This method uses Termamyl SC DS — the same heat-stable alpha-amylase The Reliable Mash runs at 190°F. It is rated far above where this rest holds it, so roughly 25°F of headroom is going unused. The likely real limit is homebrew equipment, not enzyme chemistry.
We have left the value as it was run. These are 2018 session notes, and changing a documented number to one nobody executed would be inventing a protocol. If your efficiency disappoints on this method, the rest temperature is the first thing to suspect — and record what you change. See Gelatinization and why the 190°F baseline exists.
SEBAmyl Two-Rest, Homebrew Scale
- Protocol
- GFB-HB3
- Version
- 2018 notes
- Effective
- August 2026
Two long rests, no boil, no transfer — the most straightforward of the four to run on a single recirculating vessel, and the method to start with if you are running this process for the first time. Also the thickest mash of the four at 1.25 L/kg.
Critical: The mash is roughly half the water of the other methods — recirculation and stirring matter more here than anywhere. If your pump struggles, thin the mash and record that you did.
Stage before grain-in
Thick and hot, enzyme first
- Do
- Add 20 mL Termamyl SC DS to the foundation water, then mash in sorghum malt at 1.25 L/kg.
- Add
- 20 mL Termamyl SC DS class in the foundation water
- Sorghum malt at 1.25 L/kg
- Advance when
- Mash even at 163.4°F.
- Record
- Products, doses, lots · Mash-in temperature
The first hundred minutes
- Do
- Rest at 163.4°F for 100 minutes with recirculation running.
- Add
- None
- Advance when
- Rest complete.
- Record
- Temperature stability across the rest
Down to conversion
- Do
- Add cool water to bring the mash to 145°F.
- Add
- Cool water to 145°F
- Advance when
- At temperature.
- Record
- Water added
The second hundred minutes
- Do
- Add Termamyl and SEBAmyl L. Rest at 145°F for 100 minutes.
- Add
- Termamyl SC DS class
- SEBAmyl L class
- Advance when
- Rest complete.
- Record
- Conversion start and end
Drop for runoff
- Do
- Drop mash pH to 5.4.
- Add
- Phosphoric acid to pH 5.4
- Advance when
- pH at 5.4.
- Record
- Acid amount, final pH
Vorlauf, sparge, lauter
- Do
- Vorlauf, sparge, and lauter.
- Add
- None
- Advance when
- Wort collected at or near target.
- Record
- Runoff time · Gravity vs 15.0°P
| Step | Action | Target | Add | Advance when |
|---|---|---|---|---|
| 1. Mash in: more detail | Add 20 mL Termamyl SC DS to the foundation water, then mash in sorghum malt at 1.25 L/kg. | 163.4°F (73°C) — |
| Mash even at 163.4°F. |
| 2. Liquefy: more detail | Rest at 163.4°F for 100 minutes with recirculation running. | 163.4°F (73°C) 100 min | None | Rest complete. |
| 3. Cool: more detail | Add cool water to bring the mash to 145°F. | 145°F (63°C) — |
| At temperature. |
| 4. Convert: more detail | Add Termamyl and SEBAmyl L. Rest at 145°F for 100 minutes. | 145°F (63°C) 100 min |
| Rest complete. |
| 5. Set pH: more detail | Drop mash pH to 5.4. | pH 5.4 — |
| pH at 5.4. |
| 6. Run off: more detail | Vorlauf, sparge, and lauter. | 15.0°P (1.061) — | None | Wort collected at or near target. |
Run each step with its checks and context
Use the run sheet during a routine mash. Use these expanded steps when setting up the process, training an operator, documenting a deviation, or diagnosing unexpected behavior.
Thick and hot, enzyme first
Objective
Liquefaction begins the moment grain meets water — the enzyme is already there.
Operating instruction
Add 20 mL Termamyl SC DS to the foundation water, then mash in sorghum malt at 1.25 L/kg.
- 20 mL Termamyl SC DS class in the foundation water
- Sorghum malt at 1.25 L/kg
What good looks like
Mash even at 163.4°F.
Watch for
No additional step-specific warning.
Record
Products, doses, lots · Mash-in temperature
The first hundred minutes
Objective
Trade temperature for time — liquefaction well below the 190°F production baseline, held long.
Operating instruction
Rest at 163.4°F for 100 minutes with recirculation running.
What good looks like
Rest complete.
Watch for
Stratification in a thick bed.
If this happens
Recirculate harder; stir if the pump cannot keep the bed even.
Record
Temperature stability across the rest
Down to conversion
Objective
Into the second rest without overshooting.
Operating instruction
Add cool water to bring the mash to 145°F.
- Cool water to 145°F
What good looks like
At temperature.
Watch for
No additional step-specific warning.
Record
Water added
The second hundred minutes
Objective
SEBAmyl drives saccharification through the long conversion rest.
Operating instruction
Add Termamyl and SEBAmyl L. Rest at 145°F for 100 minutes.
- Termamyl SC DS class
- SEBAmyl L class
What good looks like
Rest complete.
Watch for
No additional step-specific warning.
Record
Conversion start and end
Drop for runoff
Objective
Runoff chemistry set before the bed starts moving.
Operating instruction
Drop mash pH to 5.4.
- Phosphoric acid to pH 5.4
What good looks like
pH at 5.4.
Watch for
No additional step-specific warning.
Record
Acid amount, final pH
Vorlauf, sparge, lauter
Objective
Collect wort from the thickest mash of the four.
Operating instruction
Vorlauf, sparge, and lauter.
What good looks like
Wort collected at or near target.
Watch for
No additional step-specific warning.
Record
Runoff time · Gravity vs 15.0°P
What makes this one different
No boil, no transfer. Everything happens in one vessel at two temperatures. On a recirculating system that's close to push-button, and it's the method to start with if you're running this process for the first time.
A thick mash. 1.25 L/kg is roughly half the water of Method 1 — which concentrates the wort toward the 15°P target but makes stirring and heat distribution harder. Recirculation matters more here than anywhere.
163.4°F, not 190°F. This liquefies well below the production baseline, trading temperature for time — two 100-minute rests instead of a hot fast hold. Whether that costs anything in extract or beer quality is an open question.
Watch for
Mash thickness at 1.25 L/kg — if your pump struggles, thin it and record that you did; temperature stratification in a thick bed; and the total clock, which is over three and a half hours of rests before you even sparge.
Report back
Nobody has published results for this method at homebrew scale — which means your batch is data. Report efficiency, mash behavior, runoff, gravity against the 15.0°P target, fermentation, and what you'd change. See Research Ask #3 and tell us what happened.
Related
- Mash Methods at Homebrew Scale
- Why the 190°F Baseline Exists — the production position this method departs from