Key points
- Moisture is the commercial parameter that matters most: every extra point of water is water bought at grain prices and a storage risk.
- Mycotoxin risk in grains is origin-, season- and storage-dependent, and must be tested per lot rather than assumed.
- Energy value differs by species — the same maize has a different metabolisable energy for poultry, swine and ruminants.
- Fats and oils are traded on free fatty acid, peroxide and impurity content as much as on energy.
- Bulk density, test weight and broken-kernel percentage predict handling losses and mill performance.
In depth
What sits inside this category
Cereal grains (maize, wheat, barley, sorghum, oats), starch roots (cassava chips and pellets), milling and processing by-products (wheat bran, wheat middlings, rice bran, corn gluten feed, DDGS), liquid energy (molasses, vegetable oils, animal fats, acid oils) and starch-rich bakery or food-industry co-products. The category is defined by function — supplying energy — rather than by botanical origin, so substitutions across it are normal and formulation-driven.
How energy is measured and why numbers differ
Gross energy is a laboratory combustion value with little practical use. Feed formulation works with metabolisable energy for poultry and swine and net energy for ruminants and modern swine models, both of which are species-specific derived values, not measurements on the certificate of analysis. That is why two suppliers can quote different energy values for identical maize: they are applying different equations. Specify the calculation basis, or contract the proximate parameters (starch, fat, fibre, ash, moisture) and let the formulation system derive the energy.
Storage condition is a specification, not a courtesy
Grain arriving above its safe storage moisture will heat, mould and lose energy in the silo regardless of how good the origin was. Safe moisture depends on ambient temperature and humidity at destination, so a specification written for a temperate importer is wrong for a tropical one. Broken kernels, insect damage and dust all accelerate deterioration and should be limited in the contract alongside moisture.
By-products need tighter specifications than whole grains
DDGS, rice bran, corn gluten feed and bakery meal vary far more between plants and production runs than whole cereals do. Their nutrient profile depends on the parent process — ethanol yield, degree of oil extraction, milling fraction — and mycotoxins concentrate in by-products relative to the original grain. Buy them plant-by-plant with a specification band, not as generic commodities.
Reference table
| Material | Key energy driver | Critical parameters | Common contract limits |
|---|---|---|---|
| Maize | Starch | Moisture, aflatoxin, fumonisin, broken kernels | Moisture max 14%; toxin limits by destination |
| Wheat (feed) | Starch | Moisture, test weight, DON | Test weight min; DON limit by species |
| Barley | Starch, beta-glucans | Moisture, screenings | Moisture max; foreign matter max |
| Sorghum | Starch | Tannin level, moisture | Low-tannin varieties specified |
| DDGS | Starch residue, fat | Fat, fibre, mycotoxins, colour | Fat min/max; toxin panel per lot |
| Feed fats & oils | Lipid | FFA, peroxide value, MIU, impurities | FFA max; PV max; MIU max |
How to buy this category
- 1Set the destination safe-storage moisture before writing the specification, based on climate and silo type.
- 2Define the mycotoxin panel and limits that match the raw material, origin and destination regulation.
- 3Agree the basis for energy — declared proximate parameters or a named calculation system.
- 4Contract physical parameters: test weight, broken kernels, foreign matter, insect damage.
- 5Apply an independent survey at loading and discharge for bulk cargoes.
- 6Test on arrival and record the result against the retained sample before the lot enters the mill.
What to verify
- Moisture measured at discharge, not only at origin loading.
- Mycotoxin certificate covers the toxins relevant to the crop and origin, with limits of detection stated.
- Physical condition report — heating, caking, insect activity, odour — from an independent surveyor.
- For fats and oils: free fatty acid, peroxide value and impurity results from a recent, lot-linked analysis.
- Weight and quality certificates issued by an accepted independent party, not by the seller alone.
Typical risks
- Moisture gain in transit turning a compliant cargo into a spoilage case at discharge.
- Mycotoxin levels concentrating in by-product streams beyond the parent grain's level.
- Rancidity and oxidation in high-fat energy sources during warm-weather storage.
- Substitution or blending of by-products with lower-value fractions between contract and shipment.
- Silo self-heating causing energy loss and creating a fire and safety exposure.
Common mistakes
- Buying on price per tonne without adjusting for moisture and energy density.
- Applying a single mycotoxin limit across all species and all destinations.
- Treating DDGS or rice bran as interchangeable commodities regardless of the producing plant.
- Ignoring discharge-port storage capacity, which converts a good purchase into demurrage and spoilage.
Key terms
- Metabolisable energy
- Feed energy available to the animal after faecal and urinary losses; species-specific and calculated, not measured.
- Test weight
- Bulk density of grain, used as a rapid proxy for kernel soundness and milling yield.
- MIU
- Moisture, impurities and unsaponifiables — the standard impurity metric for feed fats and oils.
Frequently asked questions
Why do suppliers quote different energy values for the same grain?
Because metabolisable and net energy are calculated, not measured. Different equations and species assumptions give different results from identical laboratory data. Contract the proximate composition and state the calculation basis if energy is commercially relevant.
What moisture level should I specify for maize?
It depends on destination climate and storage duration. A common contract maximum is 14%, but humid tropical storage often needs 13% or lower, while short-turnaround temperate storage can tolerate the standard limit. Set the number from your storage reality, not from the offer.
Are grain by-products cheaper per unit of energy?
Sometimes, but not reliably. Higher fibre lowers digestible energy for monogastrics, variability increases formulation safety margins, and mycotoxin concentration raises testing costs. Compare on delivered cost per unit of usable energy for the species being fed.
How should feed fats and oils be specified?
By free fatty acid content, peroxide and anisidine values, moisture-impurities-unsaponifiables, fatty acid profile and an explicit statement excluding waste or recycled streams not permitted in feed at the destination.
Ingredients in this category
Related specification parameters
Related procurement checks
Other ingredient categories
Turn this into a specification
Build a structured RFQ with the parameters, tolerances and verification steps written in — free for buyers.
Start an RFQEducational reference. FeedMatch Group does not rank, recommend or promote manufacturers.