Working guidanceWe run this. It has produced results under the conditions stated on this page.
The Maltose Mash
How the three relate
The Cereal Decoction was the first approach tried. The Maltose Mash is the design that ran as Bard's original production mash, and whose chemistry — through toll-processed extract — made most of the beer Bard's ever sold. The Reliable Mash is the redesign that replaced it on the brewhouse floor and is the process we tell you to run.
These used to be numbered Mash Protocol 1, 2 and 3. The numbers were retired on 2026-08-30 because they implied a sequence that was not merely uninformative but backwards: the numbering ran 1, 2, 3 while the history ran Cereal Decoction, Maltose Mash, Reliable Mash.
The Reliable Mash is our proven brewhouse baseline; use it.
This design is not speculative, and it is not new. It was Bard’s original production mash, and its chemistry went on to make the majority of the beer the company ever sold. Running it is not a gamble.
What nobody has is a recorded brewhouse result, or any comparison against the Reliable Mash. So running it and writing down what happened is the part still missing — not the courage to run it.
What 'commercial precedent' means here, and what it does not
It was the production mash. The archive shows a fungal-alpha conversion at 132°F, pH 5.0–5.3, held 100 minutes, was Bard's original production mash, run at 75-barrel scale with a protease-blend low rest and a cereal boil in front of it, until the redesign that became the Reliable Mash replaced it.
And its chemistry did not stop when the brewhouse mash did. For most of Bard's history the beer was not mashed on the brewery floor at all. It was brewed from malted sorghum extract — concentrated wort from sorghum malt — made from Bard's own malt by third-party processors, to Bard's gluten-free specification, and then dissolved and boiled at the brewery.
The reason was contamination, not convenience: the contract brewery could not handle raw sorghum malt without cross-contamination risk, and a processor could produce the extract to a gluten-free spec that the brewhouse could not match. That extract is this design's conversion, done somewhere else and concentrated.
That path bookends the Reliable Mash rather than preceding it. Extract came first, at the earliest contract brewery. The Reliable Mash took over whenever a brewery mashed Bard's malt directly. Then extract returned at a later brewery, and once at the direct-malt one. Near the end, a few batches moved onto this sheet as a brewhouse mash again — deliberately, because the maltose made better wort and better beer.
Craig's estimate is that roughly 80% of Bard's beer by volume was brewed from that extract rather than from a brewhouse mash — which makes this design's chemistry, not the Reliable Mash's, the one behind most Bard's beer ever sold.
That figure is an informed estimate from the person who ran the company, not a total from production records. We publish it because the scale of it matters and because a reader can weigh a labelled estimate; we label it because this site does not dress recollection as measurement. If records surface that sharpen or contradict it, the number changes.
And it has been run as a mash, not just as a shape. Craig's paper log records three runs of this design at the contract brewery. A fourth attempt at a second brewery is not counted here: that run failed on equipment, not on the protocol, which makes it evidence about a brewhouse rather than about this sheet.
What none of that gives you is a validated brewhouse protocol — and the extract volume is the reason to be careful, not the reason to be confident. That beer was made from extract produced by third-party processors on equipment no reader has. It proves the chemistry converts at scale and makes beer people bought for years. It proves nothing about running this sheet in a brewhouse, which is the thing you would actually execute.
On the sheet itself the record is thin: the three logged runs record that it ran, not how it came out — no fermentation curve, no sugar profile, no sensory panel. The original production mash was replaced without the comparison ever being recorded. Nobody has run this against the Reliable Mash and written down what happened — if you do, you are answering a question the brewery itself left open.
The 132°F hold: the run sheet says 45, this page says 100
The hold is exactly 100 minutes, not "about." It is the single value on this sheet where the archive disagrees with itself, so it is stated plainly rather than left for a reader to trip over.
The V12 run sheet reads 45 minutes at this step. The operating document records 100, and the homebrew-scale version of the same process records 100 as well. Two documents against one, and the 45 is treated as a transcription error — a call made on 2026-08-15 and reviewed again on 2026-08-30.
It matters more than most numbers here: fungal alpha-amylase at 132°F is doing the fermentability work, and the hold length is the lever on the wort's sugar profile. Getting it wrong by a factor of two changes the beer, not just the schedule.
Why this design exists
The Reliable Mash works. It liquefies hot, converts hard, and finishes with a glucoamylase — which means it produces a glucose-forward wort. That was a deliberate trade for reliability and attenuation, and it still is. But it carries the known costs of glucose-heavy wort: a hot fermentation start that can stumble late, a drier beer than some styles want, and a yeast working against its own sugar-uptake order the whole way (the mechanism is on The Sugar Bible).
Conventional barley wort is maltose-forward, and yeast is at its best fermenting it. Sorghum malt cannot build that profile natively — its beta-amylase is too weak, which is the founding fact of our whole enzyme doctrine. But the external-enzyme toolbox has a maltose-leaning tool: fungal alpha-amylase. The Maltose Mash is the design that uses it.
The hypothesis in one sentence: a sorghum mash can produce a conventional maltose-forward wort — with better fermentation behavior, better yeast health, and a more beer-like finish — by trading the Reliable Mash's glucoamylase for a fungal alpha-amylase and giving the yeast a proper protein rest.
The design, as a research run sheet
Four moves, two of them straight from the Reliable Mash's proven spine — the numbers are the archive's V12 operating document, detailed in the next section:
The Maltose Mash (Proposed)
- Protocol
- GFB-the Maltose Mash
- Version
- Proposed — V12 lineage
- Effective
- August 2026
A sorghum mash designed to produce a conventional, maltose-forward wort — protease rest, hot liquefaction, then a cool fungal-alpha conversion instead of the Reliable Mash's glucoamylase finish. The numbers below follow the archive's V12 operating document (2020), the original production lineage that the Reliable Mash replaced, with one correction: the 132°F conversion hold reads 45 minutes on the run sheet and is published here as 100, the figure the operating document and the homebrew-scale version both record. Every other value, the 45-minute liquefaction included, is V12’s own.
Status: Proposed, not validated — the Reliable Mash is the baseline; use it for beer you need to work. This design ran commercially in an earlier era and the paper log records three runs of it at the contract brewery, but no results or the Reliable Mash comparison were preserved, so every run of this sheet is still a research brew. Running it against the Reliable Mash on a split wort is Research Ask #4.
Stage before the research brew
Mash in low with the protease
- Do
- Water at 2.6 L/kg with CaCl₂ to ~100 ppm and pH adjusted to 6.0. Enzymes into the water first, then sorghum malt added slowly with continuous stirring. Rest 30 minutes.
- Add
- Heat-stable alpha-amylase, 1 mL/lb (V12: Termamyl SC DS)
- Protease, 0.25 mL/lb (V12: Neutrase 0.8L)
- CaCl₂ to ~100 ppm
- Advance when
- Rest complete, mash even and moving.
- Record
- Products, doses, lots · pH and temperature · FAN sample if measuring
Intermediate rest
- Do
- Ramp to 155°F and hold 20 minutes.
- Add
- None
- Advance when
- Hold complete, mash thinning.
- Record
- Ramp and hold times
The proven spine
- Do
- Ramp to 190°F at one degree per minute through the rest of gelatinization. Hold 45 minutes with continuous stirring — V12’s own figure, and what the logged runs used. If you want more liquefaction insurance, 60 or 100 minutes are the other rungs on the ladder; say which you ran, because it changes whether your batch is comparable to ours.
- Add
- None
- Advance when
- Hold complete; mash fully liquefied.
- Record
- Ramp rate achieved · Hold time · Viscosity behavior
The maltose move
- Do
- Add cold water to reach 132°F. Set pH to 5.5. Add rice hulls if the bed needs them (V12 ran 2%). Only then add the fungal alpha-amylase and the second alpha dose. Hold exactly 100 minutes — not about. (This step reads 45 minutes on the run sheet; the operating document and the homebrew-scale version both record 100, and the 45 is treated as a transcription error.)
- Add
- Fungal alpha-amylase, 0.225 mL/lb (V12: Fungamyl 800L) — only after temp and pH are right
- Heat-stable alpha-amylase, 0.75 mL/lb
- Rice hulls ~2% if needed
- Advance when
- Hold complete.
- Record
- pH before enzyme addition · Hold time · Gravity development
End enzyme work cleanly
- Do
- Raise to 180°F, hold 10 minutes, check conversion.
- Add
- None
- Advance when
- Conversion check done; ready to run off.
- Record
- Conversion check result · Final gravity into the kettle
| Step | Action | Target | Add | Advance when |
|---|---|---|---|---|
| 1. Protein rest: more detail | Water at 2.6 L/kg with CaCl₂ to ~100 ppm and pH adjusted to 6.0. Enzymes into the water first, then sorghum malt added slowly with continuous stirring. Rest 30 minutes. | 122°F (50°C), pH 6.0 30 min |
| Rest complete, mash even and moving. |
| 2. Thinning: more detail | Ramp to 155°F and hold 20 minutes. | 155°F (68°C) 20 min | None | Hold complete, mash thinning. |
| 3. Liquefy: more detail | Ramp to 190°F at one degree per minute through the rest of gelatinization. Hold 45 minutes with continuous stirring — V12’s own figure, and what the logged runs used. If you want more liquefaction insurance, 60 or 100 minutes are the other rungs on the ladder; say which you ran, because it changes whether your batch is comparable to ours. | 190°F (88°C), ramp at 1°F/min 45 min | None | Hold complete; mash fully liquefied. |
| 4. Convert: more detail | Add cold water to reach 132°F. Set pH to 5.5. Add rice hulls if the bed needs them (V12 ran 2%). Only then add the fungal alpha-amylase and the second alpha dose. Hold exactly 100 minutes — not about. (This step reads 45 minutes on the run sheet; the operating document and the homebrew-scale version both record 100, and the 45 is treated as a transcription error.) | 132°F (56°C), pH 5.5 100 min |
| Hold complete. |
| 5. Mash out: more detail | Raise to 180°F, hold 10 minutes, check conversion. | 180°F (82°C) 10 min | None | Conversion check done; ready to run off. |
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.
Mash in low with the protease
Objective
Build free amino nitrogen for the yeast and loosen grain structure ahead of liquefaction — the work the Reliable Mash’s hot mash-in skips past. Sorghum wort runs short on FAN; this rest is the designed fix.
Operating instruction
Water at 2.6 L/kg with CaCl₂ to ~100 ppm and pH adjusted to 6.0. Enzymes into the water first, then sorghum malt added slowly with continuous stirring. Rest 30 minutes.
- Heat-stable alpha-amylase, 1 mL/lb (V12: Termamyl SC DS)
- Protease, 0.25 mL/lb (V12: Neutrase 0.8L)
- CaCl₂ to ~100 ppm
What good looks like
Rest complete, mash even and moving.
Watch for
Clumping at mash-in — the enzyme-first, grain-slowly rule applies here as everywhere.
Record
Products, doses, lots · pH and temperature · FAN sample if measuring
Intermediate rest
Objective
Initial gelatinization and thinning before the climb to full liquefaction.
Operating instruction
Ramp to 155°F and hold 20 minutes.
What good looks like
Hold complete, mash thinning.
Watch for
No additional step-specific warning.
Record
Ramp and hold times
The proven spine
Objective
Unchanged from the trusted baseline: hot liquefaction with bacterial alpha-amylase. V12 specifies the ramp rate.
Operating instruction
Ramp to 190°F at one degree per minute through the rest of gelatinization. Hold 45 minutes with continuous stirring — V12’s own figure, and what the logged runs used. If you want more liquefaction insurance, 60 or 100 minutes are the other rungs on the ladder; say which you ran, because it changes whether your batch is comparable to ours.
What good looks like
Hold complete; mash fully liquefied.
Watch for
No additional step-specific warning.
Record
Ramp rate achieved · Hold time · Viscosity behavior
The maltose move
Objective
Fungal alpha-amylase builds the maltose-forward profile — the entire point of the design. It is heat-fragile and pH-sensitive: the cool-down and pH set come first, always.
Operating instruction
Add cold water to reach 132°F. Set pH to 5.5. Add rice hulls if the bed needs them (V12 ran 2%). Only then add the fungal alpha-amylase and the second alpha dose. Hold exactly 100 minutes — not about. (This step reads 45 minutes on the run sheet; the operating document and the homebrew-scale version both record 100, and the 45 is treated as a transcription error.)
- Fungal alpha-amylase, 0.225 mL/lb (V12: Fungamyl 800L) — only after temp and pH are right
- Heat-stable alpha-amylase, 0.75 mL/lb
- Rice hulls ~2% if needed
What good looks like
Hold complete.
Watch for
Dosing the fungal alpha hot or at the wrong pH — the single fastest way to waste the run.
If this happens
If temperature or pH drifted before dosing, correct and note it; if the enzyme went in wrong, the sugar-profile claim is void for this batch.
Record
pH before enzyme addition · Hold time · Gravity development
End enzyme work cleanly
Objective
Hot enough to finish before lauter — conservative by design.
Operating instruction
Raise to 180°F, hold 10 minutes, check conversion.
What good looks like
Conversion check done; ready to run off.
Watch for
No additional step-specific warning.
Record
Conversion check result · Final gravity into the kettle
What the Maltose Mash deliberately drops: the glucoamylase. What it deliberately keeps: the hot liquefaction, the continuous stirring, the iodine endpoint, the records discipline — everything that made the Reliable Mash trustworthy.
The protease rest, and the foam question
The Maltose Mash's low rest is not the homebrew twin's low rest, and the difference is bigger than the five minutes between them. The Maltose Mash doses a protease — V12 specifies Neutrase 0.8L at 0.25 mL/lb — and holds 30 minutes at 122°F, pH 6.0. Old Traditional Bard's adds no protease at all; its 25-minute rest exists to hydrate the grist and give whatever protease-side activity is present its window. One is a dosed enzymatic step, the other is a soak.
The dosed version is well matched to its enzyme. Neutrase works at pH 5.5–7.5 and 45–55°C; 122°F is 50°C and V12's pH 6.0 sits inside the window, so the "pH 6.0 for enzyme optimization" note in the operating document is doing exactly what it says.
Where it collides with our own foam rule
Brewing literature places a boundary near 52°C (126°F): below it, peptidases chop mid-molecular-weight proteins into small polypeptides; above it, proteases break large proteins down into that mid-weight band — and mid-weight proteins are the ones that build head. Long rests below the line are described as foam-negative.
The Maltose Mash's protease rest sits below that line, is dosed, and runs 30 minutes.
That matters here more than it would in a barley brewhouse, because of what the 5 IBU hop extract rule actually does. Tetra acids bind with wort proteins in the bubble walls and stiffen them — they reinforce the architecture a gluten-free grist under-builds. Reinforcement needs something to reinforce. So the protease rest and the foam fix are not independent decisions: one may be reducing the substrate the other depends on.
The tell is that V12 prescribes both — the protease rest and, in the same document, "reduce the hops by 5 IBU, and use tetra hops post-fermentation for head retention."
Why this is a question and not a defect
Three reasons to hold the finding loosely:
- It ran, at production scale. V12's lineage was Bard's operating production mash at 75 barrels, making saleable beer for years. That is the claim this design rests on: the chemistry converts at scale. It is not the claim that the independent finished-beer panel measured this mash — that panel is dated February 2019, and the process running then already had the glucoamylase finish that defines the Reliable Mash. The panel belongs to the Reliable Mash, not here.
- This is barley science. The 52°C boundary comes from work on barley proteins. Sorghum's storage protein is kafirin, not hordein, and its foam behaviour is already different enough that the 5 IBU rule exists at all. The boundary may not transfer.
- Nobody measured it. No foam comparison with and without the protease rest exists in our records.
Nothing here weakens the 5 IBU practice — it worked in production and it is the best single-ingredient foam fix this site knows. The open question is whether it could work from a stronger starting position.
One split-wort experiment answers it. Same grist, same water, same everything downstream. Half gets the 30-minute dosed protease rest at 122°F; half skips it. Both get the 5 IBU tetra addition. Measure FAN on both worts, then score foam on the finished beers — head height, retention time, lacing.
If the protease half ferments better and pours as well, the question is closed and the Maltose Mash keeps its rest. If it pours worse, the interesting follow-up is a third arm at 55°C, still inside Neutrase's window but above the foam boundary. Send results.
Why 155°F and not 153°F
The homebrew twin holds its intermediate rest at 153°F; the Maltose Mash holds 155°F. Two degrees looks like transcription drift and is not.
Sorghum starch gelatinizes across 154–178°F. the Maltose Mash's 155°F sits just inside that range — its step objective says "initial gelatinization and thinning," and at 155°F it genuinely begins opening starch before the climb to full liquefaction. The twin's 153°F sits just below the range and deliberately does no gelatinizing at all; its next move is a hard boil, which opens everything at once.
Each figure is correct for the protocol it belongs to. Standardising them would make one of the two steps stop doing its job.
Getting from 190°F to 132°F without wrecking your mash thickness
Step 4 says "add cold water to reach 132°F" and does not say how much — and neither does the homebrew-scale version, which specifies 0.5 L/kg and then also says to add water until the grist reaches temperature. That is not sloppiness in either document; the volume genuinely depends on what you cool with, and the answer changes the mash more than most brewers expect.
Cooling a 2.6 L/kg mash from 190°F to 132°F means removing roughly 405 kJ per kg of grain. What that costs you in dilution:
| Cooling medium | Needed per kg grain | Mash ends at |
|---|---|---|
| Tap water, 60°F | 2.42 L | 5.02 L/kg |
| Cold liquor tank, 45°F | 2.00 L | 4.60 L/kg |
| Glycol-chilled liquor, 35°F | 1.80 L | 4.40 L/kg |
| Ice, 32°F | 0.72 kg | 3.32 L/kg |
Ice is about 3.4× more effective per kilogram than 60°F water, because melting absorbs a large amount of heat before the meltwater warms at all. The arithmetic: a kilogram of 60°F (15.6°C) water cooling a mash to 132°F (55.6°C) absorbs ~167 kJ as it warms 40°C; a kilogram of 32°F ice absorbs ~334 kJ melting plus ~232 kJ warming its meltwater the full 55.6°C — about 566 kJ, or 3.4× the water figure. Cool with tap water and you roughly double the mash; cool with ice and you add about a quarter of the liquid for the same temperature drop.
That matters at this step specifically. The 132°F hold is where the fungal alpha-amylase does the work the whole design exists for, and a mash at 5 L/kg is a substantially more dilute enzyme and substrate environment than one at 3.3 L/kg.
What production actually used: a glycol-chilled cold liquor tank, or ice, chosen deliberately to keep the added volume down. Letting the mash coast down with the heat off is a third option that works on paper and was never used here.
Ice added to the mash is brewing liquor. Bagged retail ice comes from water you have not seen a report for, with mineral content and treatment you cannot predict, and it lands in the mash at the moment you are trying to control pH and enzyme conditions.
Freeze your own brewing water 24 hours ahead and you know exactly what you are adding. This site asks for lot identity on grain and a documented supply chain — an unqualified water input at the conversion step is the same problem wearing a different hat. See Water, Minerals, and pH.
The temperature is the target; the volume is yours to plan. Record what you actually added — it is the difference between a repeatable mash and one that lands somewhere new every batch.
The documented design: the V12 protocol
The archive holds the design written as an operating protocol — the twelfth revision of Bard's "Adjusted Brewing Plan" (2020), with numbers:
| Stage | V12 as written | Doses (per lb sorghum malt) |
|---|---|---|
| 1. Mash in | 122°F at 2.6 L/kg; CaCl₂ to ~100 ppm; pH 6.0 "for enzyme optimization"; malt added slowly with continuous stirring; rest 30 min | Termamyl SC DS 1 mL + Neutrase 0.8L (protease) 0.25 mL — in the water first |
| 2. Thinning rest | Ramp to 155°F, hold 20 min | — |
| 3. Liquefy | Ramp to 190°F at 1°F per minute, hold 45 min | — |
| 4. Convert | Cold water to 132°F; pH to 5.5 for the fungal alpha; rice hulls "if needed" at 2% (basis unstated in V12; the site's hull convention is percent of malt weight) | Fungamyl 800L 0.225 mL + Termamyl 0.75 mL |
| 5. Mash out | 180°F, 10 min, check conversion | — |
| 6. Boil | — and the protocol itself writes in the head-retention rule: reduce the hops by 5 IBU and replace them with tetra hop extract post-fermentation | — |
The table is the archive as written, and the run sheet at the top of this page matches it everywhere except one number.
| Value | V12 as written | Published here | Why |
|---|---|---|---|
| 132°F conversion hold | 45 min | 100 min | The operating document and the homebrew-scale version of the same process both record 100. Two documents against one, so the 45 is treated as a transcription error. |
The 190°F liquefaction stays at V12's 45 minutes, deliberately. Sixty is this site's liquefaction baseline and is the safer number, so it is fair to ask why this sheet does not simply use it.
Because the logged runs used 45. This page's whole ask is that someone runs it against the Reliable Mash and reports what happened — and a batch run at 60 is not comparable to the ones already in the paper log. Publishing our preference here would quietly cost the comparison the page exists to produce.
So: run 45 to produce comparable data. Run 60 or 100 if you want the liquefaction insurance and the certainty matters more to you than the comparison. Either way, say which you ran.
That is this page's design, dose for dose — protease rest, hot liquefaction, cool fungal-alpha conversion, 180°F finish — written as a production operating document. What the archive still lacks is any recorded result or the comparison that made the Reliable Mash win.
What would have to be true
The design stands on four claims, each testable and each honestly unproven at scale:
- The protease rest raises wort FAN meaningfully in a sorghum mash — measurable by a before/after FAN assay.
- Fungal alpha at ~132°F converts a liquefied sorghum mash to target gravity in production time — measurable by gravity and hold length.
- The resulting wort is genuinely maltose-forward — measurable by an HPLC sugar profile.
- The fermentation improves: steadier attenuation curve, cleaner finish, healthier yeast crops — measurable against an the Reliable Mash control batch of the same recipe.
A fifth, softer claim rides along: a maltose wort plus better FAN should improve the finished beer's balance and head — worth scoring, hard to prove.
How to run it as a research project
Run it as a comparison or do not bother: the same recipe through the Reliable Mash and the Maltose Mash, everything else held still, judged on FAN, sugar profile, fermentation curve, finished gravity, flavor, and foam. One batch is an anecdote. A repeat across malt lots is a result. Bench scale first — the malt-lab mash process is the right harness — and the validation checklist on the 190°F baseline page applies to every claim above.
If you run this — at any scale — we want the data, whichever way it went. A failed run documented honestly is worth more to this site than a success story without numbers.
Related Pages
- The Sugar Bible
- The Reliable Mash: Enzyme Mash
- The Cereal Decoction: Decoction/Cereal Mash
- External Enzymes
- Yeast Nutrition
- Why the 190°F / 60-Minute Baseline Exists
Source and Validation Notes
This proposal is Gluten Free Brewer's own synthesis: it combines Bard's commercial production experience (the liquefaction spine, the records discipline), published enzyme and yeast-fermentation science, and standard industry mashing practice into a design we believe is the logical next protocol. Archive records show this design's core — the 132°F fungal-alpha conversion, 100 minutes, pH 5.0–5.3 — as the operating production process at 75-barrel scale before the the Reliable Mash redesign; Craig's account and the recipe documents agree, and no comparison data or decision rationale was preserved. Nothing here is a validated specification; every value is a hypothesis stated so it can be tested and, if wrong, corrected in public.