How Temperature Variation Affects Your Stored Grain

Alt-Text: A grain silo base

One of the most critical and challenging post-harvest tasks is the proper storage of harvested grains to maintain quantity and quality. Keeping the grains dry and in moderate temperature conditions is essential through aeration or regular turning.

While this may sound simple, it’s relatively not that simple. Farmers are faced with the challenges of keeping track of grain temperature data, which helps them know when to aerate and when not to. This means that a simple act of forgetfulness could cost them a significant loss. 

This article aims to explain how variable temperature affects your stored grain and how you can proactively protect your grain.

Temperature and Moisture

Understanding how temperature affects your grain will help you decide efficiently how to aerate.

Grains are known to be good insulators, i.e., they can retain heat when undisturbed. Convection currents occur, leading to moisture and condensation when the grains are left undisturbed for a given period.

The differences between the stored grain temperature and the outside temperature would determine the moisture level and condensation within the grain. For instance, the higher the grain and outside temperature differences, the higher the convection current, and the more condensation and moisture occurs.

Check Grain Moisture Content

Fungi and insect infestation occurs when the moisture content of the grain goes beyond standard requirements because it creates a conducive environment for them to thrive. When the grain temperature is not checked regularly and managed, convection currents may lead to grain surface condensation.

One way to test the moisture of stored grain is to collect grain samples from random sections of the grain bin every three to four weeks. The grains are then placed in a sealed plastic container before testing.

But this method is not very effective due to the inefficiencies that might arise during the sample collection process. Another way to manage the stored grain is to test grain temperature using temperature monitoring devices.

Check Grain Temperature

Two common ways to check grain bin temperature are, either by  installing permanent temperature sensing cables or using a more advanced method such as electronic temperature sensor probing devices.

You may also check the temperature of the grain through other methods, such as using a metal rod if electronic devices or permanent sensing cables are not available.

How does Grain Aeration Work?

Aerating your grain on time can save you from a significant loss

Aeration preserves your grain by keeping them dry. It cools the grain to reduce temperature and moisture migration, thereby preventing the occurrence of condensation and convection current.

Grain aeration is determined by its physical characteristics and class. Grain class and storage configuration impact its static pressure, which also determines the aeration fan requirements. So, when there is an increase in storage height or a change in grain class, the time it takes for efficient aeration also changes.

Ways to Use Aeration Systems

  • Aerate harvested stored grains as soon as possible to reduce the temperature below 18°C
  • Aerate when the ambient temperature falls below grain temperature
  • Know the static pressure of the grain to choose the right fan and motor

Alternative Cooling Methods

  • Turn the grain outside the bin when the ambient temperature falls below 15°C
  • Until the grain temperature reaches 15°C, turn the grain every two to four weeks (this mostly require you to remove one-third of the grain from the bin and put them back again)
  • Use grain chillers to reduce grain temperature when the ambient temperature is above 20°C. Grain chillers keep the grain cool for an extended period because of its insulating characteristics.
  • Use grain mixing and stirring equipment to maintain uniform temperature and moisture.
  • Stirring equipment moves grains from the lower and central part of the storage to the top to avoid temperature concentration and moisture caused by convection current. This method can be used alongside the aeration method.

Keeping your grain secured requires constant and efficient grain temperature monitoring. To avoid insect infestation or mold, it’s essential to invest in grain security systems. And the most efficient systems currently being used in the industry are the temperature electronic sensing devices. Visit here to learn more.