Stop the rot: moisture balance in grain storage
- September 26, 2019
Safe grain storage requires the right moisture level. Temperature also plays a part, but biological contamination thrives in overly moist environments. Whether it’s mites, fungi, or bacteria, each can destroy a crop, leaving it unsellable.
Just how important is moisture level?
Reducing moisture content of stored grains to under 13% for soy beans and under 15% for corn will inhibit the growth of fungi, bacteria and insect infestations. Those figures drop to 11% for soy beans and 13% for corn if they are to be stored for a year or more. But if the grain becomes too dry there’s another problem—damage in handling or transport. There’s little point protecting a crop from all the threats of contamination only for a supplier to deliver broken grains that are more vulnerable to mould and insect infestation from that point onwards. Shrinkage is another problem when grain gets too dry.
Getting moisture content “just right” for maximising profits
Maintaining a healthy equilibrium in the moisture content of stored grains requires consistent monitoring, best done by using a moisture sensor, and appropriate aeration. That’s assuming that the grains have been dried sufficiently before storage. They can dry in the bins but only if they’ve been pre-dried to close to the optimum initial storage moisture content of 15%. Clearly there’s an interplay between temperature and airflow in attaining optimal conditions. Grains will naturally lose moisture as they cool. But weather conditions vary and over winter, the cold air causes moisture uptake. Aeration needs to be strictly controlled. Igrain aeration solutions include fans that can be switched on as needed to regulate temperature and moisture levels and more advanced systems can include automation to achieve a target condition and use of an advanced system that takes into account climate and seasonal variation provides the most efficient solution.