Before Flavour Comes Function
Wheat functionality is the ability of a grain to perform through cultivation, milling and its intended final use. For pasta, that means more than high protein. Gluten quality, grain density, enzyme activity, milling behaviour, extrusion, drying and cooking performance all matter too.
Every August, once the combines have finished and the grain is in, farmers and millers start using a word that sounds simple but carries a lot of weight behind it.
Functionality.
It is the word Oscar Harding, who farms and mills at Duchess Farms, comes back to more than any other when he talks about his trial plots.
"Function before form", he says.
Before anyone asks whether a wheat tastes good, smells good or has a nice story behind it, there is a quieter and much less romantic question that has to be answered first.
Can it actually do its job?
Functionality changes meaning as a grain moves down the chain. In the field, it means surviving and producing a harvest. At the mill, it means yielding useful, consistent flour. In the pasta room, it means forming, extruding and drying reliably. In the pan, it means holding together and eating well.
This year, that question has mattered more than usual. Much of the country experienced one of the driest summers in recent memory, and at Duchess Farms Oscar spent most of it waiting for a little humidity that never really arrived.
A dry summer does not just mean a smaller harvest. It can change what a wheat is actually capable of once it is milled and turned into flour.
It helps to understand functionality not as a single verdict but as a series of gates.
In this year’s development field at Duchess Farms, around twenty wheats were growing side by side, and only a handful stood out strongly enough to merit further testing. Fewer still will make it through milling. Fewer again will make it as far as an actual batch of dough.
What follows are three of the first measurements commonly available on a UK grain sample sheet: the ones that help decide which wheats deserve to be investigated properly.
Protein, and the part protein does not tell you
Protein is usually the first number anyone looks at, and for good reason. It has a real hand in how a dough behaves and how much bite pasta keeps once it is cooked.
But protein on its own is only the starting point.
Gluten is not one uniform substance. Its behaviour depends partly on two broad families of storage protein, glutenins and gliadins, their individual composition, and the network they form once flour is hydrated and worked.
Two wheats can both measure fifteen per cent protein and behave quite differently once they meet water and a mixer: one turning into a dough with real strength and elasticity, the other falling short despite the number on the label looking identical.
Modern durum cultivars have been intensively selected for milling and pasta-making performance. Heritage and less-commercialised wheats often have long histories of cultivation behind them, sometimes centuries, but they have rarely been selected as systematically for modern pasta manufacture.
That is exactly why Oscar’s trial plots exist.
Specific weight, or hectolitre weight
Specific weight, also known as hectolitre weight, measures how densely packed a sample of grain is. It is calculated by weighing a fixed volume of it.
A high specific weight is often a sign of well-filled, sound grain, although kernel shape, size distribution and how efficiently the grains pack together also influence the result. It is usually associated with a better milling outcome, though it is not a guarantee of one.
This is where the strangeness of this year’s harvest really shows itself.
A drought severe enough to shrink a grain can also lower specific weight, because the kernel never quite fills to the size it might reach in a wetter year.
What has been genuinely encouraging at Duchess Farms is that varieties such as rivet and krivet appear to have held their density better than expected under the conditions, among the other wheats growing around them this season.
Hagberg falling number
The Hagberg falling number sounds the most technical of the three measures, and in a narrow sense it is, although the idea behind it is fairly intuitive.
It is an indirect indication of alpha-amylase activity, based on how quickly a heated flour-and-water slurry loses its viscosity.
Alpha-amylase begins breaking down starch if a grain starts to sprout while it is still standing in the field, something that is more likely to happen after heavy rain shortly before harvest.
A sufficiently high falling number generally indicates low alpha-amylase activity and little pre-harvest sprouting. A low one is a warning sign, because flour milled from that grain may behave unpredictably in a dough.
This year’s dry conditions have made pre-harvest sprouting less likely, so Hagberg may prove one of the easier boxes to tick.
The sample results will tell us whether that expectation was right.
What the numbers do not cover
Protein, specific weight and Hagberg are three of the measures that tend to appear on a UK grain sample sheet, but they are not the whole of what Oscar means by functionality.
Moisture at harvest matters enormously in its own right. Wetter grain costs more to dry, stores less safely and carries a higher risk of mould. A wheat can score well on every other measure and still be a headache if it comes off the field too wet to store.
Agronomic performance sits alongside all of this.
Before a wheat is worth testing for end use, it must first perform reliably in the field, standing up to yellow rust, brown rust, septoria and mildew without needing constant intervention.
Height brings its own trade-off. A tall wheat tends to shade out weeds well, which matters enormously on an organic farm where herbicides are not available and crop architecture has to do much more of the weed-control work.
But a wheat that grows too tall can lodge, falling over before harvest. That makes it harder to combine cleanly and can damage the quality of the grain itself.
Growers are constantly balancing a plant’s height against its ability to stay standing.
For Oscar, the ability to outcompete a weed is itself a form of functionality, not a side benefit. It is one of the ways his approach differs from more conventional growing, where weed control is assumed to come mainly from a sprayer rather than from the plant itself.
Where conventional pasta and wholegrain pasta part company
Almost everything discussed so far belongs to the language of grain trading and roller milling, and for good reason.
Most cereal science behind pasta quality has been developed around durum wheat and industrial semolina, where the objective is to separate the endosperm from the bran and germ as cleanly as possible.
In that world, a trait called vitreousness matters a great deal.
A vitreous kernel is hard and glassy when cut open rather than soft and chalky. It can provide a useful clue to denser endosperm, milling behaviour and the internal structure of the grain: qualities that help predict how efficiently it can be separated into clean semolina.
We do not separate the grain that way.
At Carleschi, we stone mill the wheat and sieve it only lightly, keeping almost everything the grain grew with.
The flour is sifted at approximately 500 microns, not to produce a refined flour or maximise conventional extraction, but because there is a practical limit to how much coarse bran a pasta dough can tolerate before extrusion becomes inconsistent.
Smaller particles are not separated and discarded. They remain in the flour and become part of the pasta.
Vitreousness is still a useful clue, but it stops being the destination it is for a conventional durum miller. We are not trying to isolate what the industry considers the best part of the grain.
We are trying to make the whole grain work.
Wholegrain functionality
That shift changes the questions worth asking.
We think of this as wholegrain functionality: the ability of a wheat to perform when the bran, germ and endosperm remain together, rather than being separated during milling.
Instead of asking how efficiently a wheat can be turned into semolina, we ask how the whole grain behaves as flour.
How much water does it absorb?
How does the bran affect the way the dough comes together? Does it interrupt or interfere with the gluten network as it forms?
Does the wheat mill cleanly on a stone without overheating or producing too many fine particles?
What particle-size distribution produces the best wholegrain pasta, rather than the highest semolina extraction?
How readily do the flour proteins hydrate and form enough structure during mixing and extrusion?
Does the dough pass consistently through a bronze die?
Does it dry without cracking or warping?
Once cooked, how much solid material escapes into the water as cooking loss? How firm does the pasta remain, and does it hold its texture through to al dente?
The wheat has not changed.
The questions have.
Those are the questions we are beginning to ask of rivet, krivet and the other wheats in Oscar’s trial field.
They are not questions the conventional pasta industry has had much reason to ask, because it is not usually working with the whole grain in the first place.
But if wholegrain pasta is going to fulfil its potential, they are questions worth answering properly.
A note on end use. There is no single definition of a good wheat. A bread miller, a biscuit maker, a pasta maker and a farmer may each need different, and sometimes conflicting, traits from the same grain. The measurements in this article are screening tools, not universal grades of quality. A wheat is more or less suited to a purpose, not simply high quality or low quality in the abstract.
The first gate, not the finish line
None of these measurements tells you whether a wheat will make exceptional pasta.
They tell you whether it is worth finding out.
Most wheats in a trial field are rejected before anyone tastes them. Some fail agronomically, some mill poorly, and others reveal their weaknesses only during mixing, extrusion, drying or cooking.
Oscar describes the process less as selection than elimination.
Function before form is not a slogan so much as a filter, applied at every stage.
This year, rivet and krivet have emerged from the field as two wheats worth putting through the next one.
Whether they earn a permanent place at Duchess Farms, and eventually in more of our pasta, will depend on what happens at the mill, in the pasta room and finally in the pan.
For now, they have earned the right to be asked the next question.
Frequently asked questions
What makes wheat suitable for pasta?
It needs to perform at several stages: in the field, through milling, during mixing and extrusion, through drying and finally during cooking. Protein content is relevant, but gluten quality, flour behaviour, processing conditions and cooking performance all have to be tested together.
Is high-protein wheat always better for pasta?
No. Total protein matters, but protein composition and gluten strength mean two wheats with the same protein percentage can behave very differently once made into dough.
What is the difference between wholegrain pasta and semolina pasta?
Semolina pasta starts by separating the endosperm from the bran and germ as cleanly as possible, and most cereal science around pasta quality has been built for that system.
Wholegrain pasta such as ours keeps the bran and germ in the flour. That changes which measurements matter most and asks different questions of the same wheat.
What is a good Hagberg falling number?
There is no universal pasta threshold. In UK bread milling, 250 seconds is a common contractual minimum for some breadmaking wheats, although end-use requirements and buyer contracts vary. Pasta wheat is assessed differently from bread wheat.
What is specific weight?
It is the mass of a fixed volume of grain, normally expressed in kilograms per hectolitre, which is why it is also called hectolitre weight. It is one indicator of how well a grain filled out during ripening.
Further reading
If you would like to explore the science behind wheat quality, milling and pasta making in more detail, these are useful places to start.
- AHDB: Highly Heritable Wheat Quality Traits — An accessible introduction to grain characteristics influenced strongly by genetics, including protein content, specific weight and Hagberg falling number, and how weather and crop management affect them.
- AHDB: End-use Groups and Specifications for Milling Wheat — A practical guide to how UK wheat is classified for different markets, with typical specifications for protein, moisture, specific weight and Hagberg falling number.
- AHDB: Assessment of Milling Wheat Varieties — An explanation of how Recommended List trials evaluate milling wheats and why grain quality is assessed alongside agronomic performance.
- AHDB: Annual Cereal Quality Survey — A yearly snapshot of grain quality across Great Britain, showing how weather can alter protein content, specific weight and Hagberg falling number from one season to another.
- International Journal of Food Science and Technology: Durum Wheat Quality — A Multidisciplinary Concept — A detailed review of what makes durum wheat suitable for pasta, including vitreousness, protein quality, milling performance and end use.
- UK Flour Millers — Background on flour milling, wheat quality and the UK milling industry.
- Cereal Chemistry — A scientific journal covering wheat chemistry, dough rheology, milling, cereal processing and end-use quality.
Continue reading in Pasta Journal
- Meet Oscar Harding: growing wheats worth milling
- What is rivet wheat?
- Krivet: from trial field to pasta
- What wholegrain really means
- Why we make slow-dried pasta
- Fibre is not something you add: it is how wheat is built
Notes
This article reflects our practical experience working with British-grown grain, stone milling and wholegrain pasta production, alongside published information about wheat quality and cereal science.
The 2026 Duchess Farms trial results discussed here are preliminary. Laboratory analysis, milling trials and pasta-making tests will determine which wheats progress further.