Coverage Map: Where the Research Runs Out
A directory is most useful where it shows blank space. Each directory page ends with a Research gaps section that says, with a date, what we searched for and did not find. This page collects the first line of each, so a researcher, a funder, or a student can see the whole shape at once. The lines are ours; the evidence is on the linked pages, and every gap there carries the search that found it.
Three rules carry over from the directory family. A gap is documented, not speculated; where we say "nowhere we can find," we say what we searched. Coverage is US-centered by design, with international anchors where the science is foundational. And a line here is a map reference. A thin field is a documented gap, which this family publishes on purpose, and nothing on this page ranks one field against another.
Grains
| Directory | What the field has | Where it runs out |
|---|---|---|
| Sorghum | The deepest science in the family: decades of malting research, federal labs, international funders | No US brewing-grade supply chain; a national malt standard is rare (South Africa has one); no peer-reviewed cost model ; production-scale lot data scarce to absent |
| Millet | The inversion of sorghum: commercial malting and breweries using it today | A thinner scientific base; no checkoff we know of ; a published varietal study but no released malting dataset |
| Rice | Enormous research infrastructure and economics | Base-malt science one US program deep; nobody breeds rice for brewing that we know of ; a cultivar study but no released dataset |
| Buckwheat | A complete malting corpus, and the family's clearest case of a private company funding the science it needed | The corpus is frozen; public breeding nearly vanished in North America; the export paradox is unexamined |
| Corn | The most-researched crop on earth and a century inside American lager | Almost no malt research; corn malt barely exists commercially; no funded, sustained corn-brewing program |
| Teff | A real but narrow scientific toehold, an ancient fermentation tradition, a US commercial crop | No published US teff malting anywhere we can find; grain identity underdeveloped; no funder owns the brewing question |
| Fonio | Brewing visibility driven by the craft beer industry rather than cereal science | The malting corpus is dormant; how the campaign beers were made is undocumented; no US cultivation we have found |
| Quinoa & Amaranth | Two pseudocereals whose records travel together | No quinoa or amaranth malt sold commercially anywhere we can find (buckwheat, the third pseudocereal, is malted) ; amaranth's brewing science stops at feasibility ; no US program touches malting |
One gap runs under all eight: the information layer wheat and barley buyers take for granted, per-lot reporting and a shared specification, is missing for every grain here. Open Problems opens with it.
Enzymes
| Directory | What the field has | Where it runs out |
|---|---|---|
| Internal enzymes | Malting science: how germination builds activity and how it is measured | No lot-level dataset ; no gluten-free enzyme development standard ; methods borrowed from barley; the molecular era barely started; nobody funds it as a field |
| External enzymes | The commercial products, their makers, the application research, the regulation | The dose question is unpublished, by breweries and suppliers alike; gluten-free-specific product guidance scarce; no public funder touches the wing |
| Koji & grown enzymes | Two thousand years of practice on rice, a deep Japanese literature, and two sorghum studies carried to finished lager | Sorghum is the gap, not commercialisation: the sorghum-koji work is one research group's, at bench scale, and our own position is documented, not adopted |
Fermentation
| Directory | What the field has | Where it runs out |
|---|---|---|
| Yeast & Fermentation | Two US groups working different halves of the subject; the aroma gap measured | Strain attenuation on gluten-free wort unpublished by anyone ; five of nine grains have no controlled fermentation data ; the aroma gap has a candidate explanation and no test |
| Traditional Fermentation | Fifty-two traditions listed; the prior art for every grain in the family | The Nigerian conversion not mined as evidence; quality described but not quantified; the starter cultures of Northeast India essentially unexamined; the mycotoxin question unresolved at scale |
Process and proof
| Directory | What the field has | Where it runs out |
|---|---|---|
| Process & Equipment | The brewhouse itself and the physical problems these grains create in it | The low-temperature mash untested at commercial scale ; no protein-structure specification ; no mash filter in a gluten-free brewery we have found ; equipment claims untested independently ; the academic literature thin, and the page says so |
| Testing & Certification | The methods, the laboratories, the schemes; the suppression finding and the 2020 rule that answered it | Three analytical routes and none has displaced the reference; no gluten-free brewing sampling standard; the certification schemes' internal methods are not public |
| Flavor & Sensory | Volatile chemistry across grain literatures; trained panels used on these beers | The blind-versus-informed gap not quantified for US drinkers ; nobody has published a FAN supplementation with the volatiles re-measured ; no gluten-free lexicon ; texture discussed and rarely measured |
Context and practice
| Directory | What the field has | Where it runs out |
|---|---|---|
| Celiac & Health Research | The clinical literature that sets the thresholds everything else is measured against | The patient study is small with no follow-up we have found; antibody binding is not a clinical outcome; our archive carries the field's mail, not its literature |
| Homebrew & Home Malting | Where the category's real experimentation happens; what it has written down and where it buys | Home malting has materials but no home; the experimental record is unmeasured; no recipe database carries provenance; no competition category, so no aggregated sensory record |
Adjunct
| Directory | What the field has | Where it runs out |
|---|---|---|
| Distilling | Neighbours who run enzyme-assisted conversion as routine industrial practice, with doses and yields reported more openly than brewing's | The peer-reviewed literature has not measured gluten in a distilled spirit ; the brewing-versus-distilling comparison has never been run ; the baijiu literature unread on this side of the language barrier; whether the page belongs in the family is still open |
The notebook
Open Notebook has no coverage line, because it maps nothing. It records connections between separate studies that no single study makes, filed under the same six headings as this page, each with the papers it came from linked underneath. Where a line above says "no test," the notebook is often where the candidate test is written down.
What this map does not cover
The non-English literatures. The Nigerian sorghum-beer record, the Chinese starter and baijiu literatures, the Ethiopian and Indian fermentation traditions all appear above as gaps. They are gaps in our reading; those literatures exist, and a reader who works in those languages could close several lines on this page.
How this page changes
A directory's line changes when its Research gaps section changes: a gap closed by a search or a paper, or a new one opened. A new directory adds a line. Each change is dated below.
Changes.
- 2026-09-07 — Page created from the nineteen directories' Research gaps sections and the grain lines on the Grains landing page.
Corrections welcome — see Contact.