Safe Grain Storage
In the agri-food industry, guaranteeing the correct conservation of the cereal for long periods of time is very important to avoid its deterioration or loss of quality.
What should you keep in mind?
The increase in temperature is directly related to both the development of insects and the biological activity of the cereal.
Insects and moulds
Insects and moulds are the main contributors to grain spoilage and quality loss. High levels of temperature and humidity stimulate their growth. To prevent this, it is very important to keep the grain cool and dry.
The safe storage conditions are different depending on the grain type, but overall, a temperature below 10 ºC and moisture content below 14% provide optimal conditions for a long-term safe storage.
Monitoring temperature and moisture
Achieving good conditions for a safe storage requires limiting the grain temperature and maximum moisture content at grain reception. The recommended moisture content for grain storage depends on the grain type but shouldn’t be higher than 14%.
During the storage period, surveillance, observation and monitoring tasks of the grain are essential. The GESCASER temperature and moisture probes allow to accurately monitor the grain evolution and are an indispensable tool to assure a safe storage.
The temperature increase is directly related both to insect growth and biological activity of the grain. Furthermore, the moisture increase might also be linked to the insects’ presence, biological activity of the grain or external agents such as leaks or condensation.
In order to prevent condensation, particularly in metal silos, the installation of GESCASER anti-condensation probes and roof exhaust fans are recommended.
A helpful tool to achieve safe grain storage is grain ventilation. If this is properly dimensioned, it will be possible to cool the grain and keep it within safe conditions during the storage period, thus avoiding spoilage and the quality loss.
In general, the ventilation is used to cool the grain or to keep it within safe storage conditions. In addition to cooling, the ventilation causes a slight grain drying which can be used to correct small moisture content deviations.
- Ventilate when the ambient conditions are fresh and humid, in order to avoid weight losses due to the associated drying.
- Try to have the cereal temperature below ambient temperature. The ambient relative humidity should be around, or slightly above, the interstitial air humidity of the stored cereal (~ 65%).
- When drying your cereal is your goal, ventilate if the environment is warm and dry, since in these conditions the process is more efficient. It is recommended that the ambient temperature is higher than 10 ºC and the relative humidity lower than 65%.
The CTC + software developed by GESCASER allows three types of ventilation control:
ON / OFF: forces ON or OFF
AUTO: ventilation will work if the conditions inside the silo require it and adequate environmental conditions are met.
Psychometric: uses psychrometrics to improve ventilation performance. Ventilation is controlled based on the equilibrium moisture content of the cereal (EMG), and the ambient temperature and relative humidity; provided that conditions programmed by the user are met.