Rye flour is bought for sourdough and rye bread, where the starch and pentosans do the work that gluten does in wheat. That makes falling number and amylogram the decisive parameters, and ergot the contaminant a buyer must control, because rye is the cereal most exposed to it.
At a glance
- Types: light, medium and wholemeal, defined by ash on dry matter
- Key numbers: falling number, amylogram peak viscosity and temperature, ash
- Key contaminant: ergot sclerotia and ergot alkaloids, named in Regulation (EU) 2023/915
- Trade unit: 25 or 50 kg bags, big bags
- Deep dive: mycotoxin and ergot sampling
Grades, cuts and calibration
Rye flour types are set by ash. German Type 997, 1150 and 1370 and wholemeal are the usual reference points for EU buyers; Ukrainian standards name sifted, peeled and wholemeal rye flour. As with wheat, contract an ash band on dry matter rather than a name.
Rye bread depends on controlled starch breakdown. Falling number and the amylogram tell the baker whether the enzymes will degrade the starch during baking. Too much enzyme activity gives a sticky, wet crumb; too little gives a dry, crumbly one. Rye bakers adjust with acidity, which is why sourdough and rye go together.
Seasonality and availability
Rye is harvested in July. Wet harvests raise sprouting, which lowers falling number, and raise ergot risk.
What the buyer checks at intake
- Ash, moisture and falling number on every lot; amylogram where contracted.
- Ergot sclerotia on the grain and ergot alkaloids on the flour, against the contracted position.
- DON and other mycotoxins named in the contract.
- Sifting residue, infestation and bag integrity.
Where it is used
Sourdough and rye bread, mixed rye-wheat bread, crispbread, rye crackers and gingerbread.
Choosing the type for the process
Light rye flour suits mixed rye-wheat bread and pastry where a pale crumb is wanted. Medium types carry more bran and flavour and are the workhorse of sourdough rye loaves. Wholemeal and coarse meal go into dense rye bread and crispbread, where water absorption and fermentation time change noticeably. A bakery switching origin should run a trial bake with its own sourdough before the first full truck, because the same ash band can still behave differently in the oven.
Rye is also milled into flakes and kibbled grain for bread toppings and muesli; those formats follow the same ergot and mycotoxin controls as the flour.
Standards and routes
Bagged by curtainsider or dry container; dry, clean, food-grade equipment only.
Testing, storage and documents
Ask for a certificate of analysis per lot that names the method behind each value: ash to ISO 2171, falling number to ISO 3093 and the amylogram to ISO 7973. Ergot is checked twice: as ergot sclerotia on the grain before milling and as ergot alkaloids on the finished flour, because cleaning removes sclerotia but fragments can pass into the mill stream. DON is the Fusarium toxin most often named alongside it.
Wholemeal rye keeps less well than light flour because the germ and bran carry lipids and enzymes. Store bags off the floor in a dry, cool warehouse, rotate first in, first out, and agree a best-before period with the mill rather than assuming the wheat flour figure.
For bulk planning, see flours and milled grains and the related wheat flour specification.
Common specification mistakes
- Specifying protein instead of falling number and amylogram
- Leaving ergot out of the contract
- Buying a type name without an ash band
How to brief a supplier
- State the bread type and process (sourdough, direct)
- Give the ash band and the falling number range
- Ask for amylogram values if your process depends on them
- State the ergot and mycotoxin position by instrument
- Define packaging and label language