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Key Spoilage Indicators – why temperature isn’t the best sign of hotspots

We’re coming into the time of year when the risk of spoilage in stored grain continues to rise along with the temperatures.

This winter’s above-average trends plus roller coaster temperatures and warm days followed by cool nights mean we need to be more aware than ever of what’s happening in our bins.

Temperature changes like this increase the possibility of condensation forming in the headspace. When that happens, the grain at the top will absorb that moisture, and that’s when mold can develop, especially the more your ambient temperature rises.

Sometimes the mold is visible. Other times, you’ll see the effects of condensation in sprouting and crusting. But remember, you don’t want to actually SEE that – you want to have grain monitors installed so you don’t ever have to enter the bin.

Instead of entering the bin, be aware of your key spoilage indicators and know they need to be addressed immediately.

While we often hear that increasing grain temperature is the first sign of spoilage, the earliest sign of grain spoilage is actually an increase of carbon dioxide (CO2) rates. Why? Air currents move CO2 faster than the grain conducts heat. Temperature cables won’t detect it, but CO2 sensors will, and that’s a real-time sign that your grain is spoiling. You can get these types of notifications with OPI’s Grain Quality Sensor, specifically developed to monitor CO2.

After CO2, temperature is your next best sign of spoilage. Specifically, we say that if grain temperature is rising about 50F/week without aeration, it’s time to take action and mitigate that hot spot. Start with aeration, and if that doesn’t control it, you may need to unload the affected section of grain.

If you have a fan in the bin, turn it on and cool the grain as fast as you can. Remember, do not run fans below freezing. (We all know even with a warmer spring we’re going to get some rogue cold snaps.) If you have a bin without aeration, turning the grain is the best way to cool.

Hopefully you’re running an OPI Blue system with automated fan control, so the fans automatically turn on when it detects ambient air with cooling potential, and you minimize shrink, not to mention reduce your energy consumption. If not, you’ll want to be careful not to over dry the grain while you’re cooling. Again, this is where moisture cables come in handy.

Our best recommendation for knowing when spoilage is imminent is the OPI BLUE system with temperature and moisture cables plus CO2 sensing. You’ll get the grain monitoring capability, and you can also set Rate of Rise alarms for CO2 and temperature levels to give you early awareness. It’s the difference between chasing a problem and stopping it before it starts and preventing grain loss.

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