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Proposed: A Sorghum Malt Evaluation Standard (GFB-SME, draft v0.1)

There has never been a good standard for evaluating sorghum malt in modern brewing. Labs fell back on South Africa's SABS 235 — an opaque-beer spec — or barley procedures, or Taylor's methods, or they asked us, precisely because nothing built for the job existed. So here is our draft — sorghum malt as a character ingredient, not a conversion engine — published for the field to adopt, adapt, or tear apart.

Status: proposed, draft v0.1, never ratified by anyone. This is a discussion document in the same spirit as Mash Protocol 3: a specific, criticizable design beats an empty field. If you run a lab, a malting program, or a breeding program and this draft is wrong for your work, we want to know exactly where.

The stopgap the field has been using​

The closest thing to a prior standard is South Africa's SABS 235 (now SANS 235) — the sorghum malt specification for that country's traditional opaque-beer industry, where the malt is the conversion engine and gets traded on diastatic power in Sorghum Diastatic Units. Within its home context it does its job. The problem is what happened outside that context: labs evaluating sorghum malt for modern brewing reached for SABS 235 not because it fit, but because it was the only sorghum-shaped standard on the shelf. A spec written for sour, cloudy, unpackaged opaque beer became the default reference for work it was never designed to judge — the clearest possible evidence that the real standard was missing.

Our proposal is for the product class none of the borrowed tools were built for: clear, stable, packaged gluten-free beer brewed with external enzymes, where the malt's job is character.

The problem with every other current approach​

Where labs didn't borrow SABS 235, sorghum malt evaluation was barley evaluation with the labels changed. The reference methods — congress mash, ASBC/EBC malt analysis — were built for a grain whose malt converts itself. Run them on sorghum and the numbers mostly measure sorghum's enzyme deficit: low DP, low alpha, incomplete conversion, and an extract figure gated by the enzymes rather than the malt's actual contribution. Decades of screening data (including ours) scored cultivars DP-first because that's what the borrowed methods measure best.

Our position, proven at commercial scale: that's measuring the wrong thing. In a working gluten-free process, external enzymes own conversion. The malt's job is flavor, color, body, clean wort, and yeast nutrition. An evaluation standard should measure the job, not the handicap — and as an aside we'll defend anywhere: further research into maximizing native sorghum enzymes is effort the brewing side of the field doesn't need.

Principle 1 — Evaluate in an external-enzyme reference mash​

Replace the congress mash with a standardized enzyme-added mini-mash: fixed heat-stable alpha-amylase and saccharification doses (specified per gram of grist, products and activities stated), a fixed temperature program modeled on the 190°F liquefaction baseline, fixed water ratio in L/kg. Conversion is held constant by design — so every difference between samples is the malt, not the enzymes.

From that one mash, the measures that matter:

MeasureWhy it's first-class
Extract (% d.b., method stated)The malt's material contribution, ungated by native enzymes
Wort turbidity + clarityThe practical problem that decides whether sorghum beer is drinkable — measured per sample, as the 2002–2004 program already did
FAN (ppm)Sorghum's real deficit; drives yeast performance downstream
Wort colorCharacter contribution, kiln response
Wort pH and viscosityProcess-fit signals
Defined sensory panelMalt is for taste — wort and hot-steep aroma/flavor scored against a published lexicon, not "seemed fine"

Native enzyme measures (DP, alpha-amylase) become optional descriptive data — reported if measured, never a ranking criterion, and always with the unit system named.

Principle 2 — The reference malting schedule​

Screening comparisons need a shared malting method. We propose the Madison bench schedule as the reference, because it's documented and we've published its output: 26-hour steep (8h wet / 1h air / 8h wet / 1h air / 8h wet) at 24°C; germination at 24°C with spray-watering to 41% moisture (wet basis); endpoint at 1:1 acrospire-to-grain length (~72 hours bench scale); five-stage kiln finishing at 85°C. The 85°C finish is deliberate doctrine — character over enzyme survival.

Principle 3 — Mandatory declarations​

Every archived screwup in our own records traces to an unstated basis. So the standard makes these declarations mandatory on every report:

  1. Moisture basis — wet or dry, on every moisture and extract figure.
  2. Units on every enzymatic measure — °Lintner, °WK, ASBC, or SDU, never bare numbers. (Our own 2002–2004 dataset carries an unlabeled DP column; it's published with a warning because the units died with the worksheet. Don't be that worksheet.)
  3. Ratios in L/kg, with any local units in parentheses.
  4. Germination length and scale — bench and production timelines differ by days.
  5. Cultivar identity — named, or explicitly declared anonymous. Anonymous grain is a different, lesser class of result.

Principle 4 — Rank for the beer, not the assay​

A scoring framework, not a single index: clean wort and real extract are gate criteria; flavor panel differentiates; FAN sets the nutrition plan; color maps the malt to styles. A cultivar with modest numbers and a clean, flavorful wort outranks a hazy DP champion — because the first one makes better beer with external enzymes, and the second one makes a mess with slightly less enzyme.

What would make this a real standard​

Adoption, criticism, and iteration — in that order. Specifically: labs running the reference mash and reporting friction; breeding programs (the University of Nevada, Reno program is building exactly the methodology this draft addresses) comparing it against their own protocols; and anyone publishing sorghum malt data adopting the mandatory declarations even if they reject everything else. The declarations alone would fix half the field's comparability problem.

Version history: v0.1, first public draft, 2026-08-08. Substantive revisions will be recorded here.

Source and Validation Notes​

This proposal synthesizes Bard's commercial malting and brewing experience, the USDA-ARS screening program's documented methods, and the site's published doctrine. It is a draft authored to be criticized; nothing here has been ratified by any standards body, and the reference-mash enzyme specification (products, doses, activities) is deliberately left at v0.1 as the first thing adopters should pressure-test with us.