Storing Canola Safely: Moisture, Oil and Heating Risk
Canola stores well when it's dry and cool, and badly when it isn't. Here's why its moisture limit is 8%, why it heats, and how to aerate it.
SiloSense IQ ·
Canola is one of the most valuable crops on many Australian farms — and one of the least forgiving in storage. It can go from sound to heating faster than cereals, and the damage hits both price and oil quality.
Why canola is different
It’s an oilseed. Canola seed is roughly 40% oil or more. Oil doesn’t hold water, so the water in a seed sits in the non-oil part. At the same moisture percentage, canola is effectively wetter than wheat from a mould’s point of view. That’s why the receival limit is 8%, compared with 12.5% for wheat and barley, and why many storers aim for about 7% for long-term storage.
The seed is small. Small seeds pack tightly and resist airflow. The same fan delivers noticeably less air through a silo of canola than through wheat, so cooling takes longer.
Oil quality can deteriorate. Warm, damp canola can develop higher free fatty acids and off-odours, which buyers penalise.
Heating risk
Canola harvested warm, or stored above safe moisture, can start heating within days. Heated canola can cake, darken, and in severe cases become unsaleable. Because the seed is small and tightly packed, a hot spot can be hard to cool once it starts.
Risk factors to watch:
- Seed harvested above 8% moisture or with high green seed content.
- Weed seeds and trash, which carry more moisture and block airflow.
- Warm harvest temperatures with no aeration.
- Condensation at the top of the silo.
Storage tips
- Harvest and store dry. Aim for 8% or below, and lower for long storage.
- Clean the sample. Removing weed seeds and trash improves airflow and reduces moisture pockets.
- Aerate promptly. Cool canola as soon as it’s in, and keep cooling until the top is cool.
- Check your fan capacity for canola. Expect lower airflow than with cereals — check how much air your fan really delivers through canola.
- Watch the top layer. Condensation and migrating moisture collect there.
- Monitor often. Canola changes faster than cereals; weekly checks may be too slow.
Using the right moisture model
Moisture estimated from air temperature and humidity in the grain depends on the crop. Canola’s equilibrium moisture for a given humidity is much lower than wheat’s, so any system that calculates moisture must use a canola-specific model — a wheat model would badly overstate canola moisture.
How SiloSense helps
SiloSense IQ lets you set the commodity for each silo and calculates moisture at every level using that crop’s own model, for 12+ commodities including canola. The dashboard judges each silo against its crop’s limits, and the headspace CO₂ sensor helps flag heating early.
Aeration Manager runs fans only on suitable air, and SiloSense IQ+ uses canola’s 8% and 7% limits to make aeration decisions automatically.
Request a demo to see canola moisture on the dashboard.