Grain aerator - the guardian of grain quality
Good harvests are the foundation of agricultural success - there is no doubt about it. It is a truism to say that practically the entire development of agrarian technology can be reduced to the issue of maximizing yields while limiting labor input.
However, harvesting is not the end of a farmer's work. Proper storage of harvested crops can also be quite a challenge. This is due to the fact that the fruits of farmers' labor are never lacking in eager guests, of course, referring to all kinds of parasites and pests.
As evidence that the problem of unwelcome guests in granaries is as old as agriculture itself, we can consider, for example, the domestication of cats. It is no coincidence that our mouse-hunting pets appeared in human dwellings just when prehistoric farmers began growing wheat and oats.
Today, we know that for the crops gathered by humans, much more dangerous than rodents with a bad reputation can be significantly smaller, but ubiquitous pests - fungi and bacteria.
In the fight against their proliferation, technology supports us, including our hero for today - an aerator.
Grain aerator - what is it and how does it work?
Grain aerator is a device used to aerate grain, which improves its quality by increasing enzyme activity and improving the grain's "breathing." The aeration process prevents grain spoilage, mold growth, and loss of quality, which is particularly important for storage.
Aerators are commonly used in grain silos and warehouses, as well as in the milling industry. Electric grain aerators became popular in the 1960s. The latest models, in addition to their preserving function, are also equipped with systems for monitoring grain composition parameters, such as humidity and temperature.
How does an aerator work?
A grain aerator is a longitudinal device that resembles a large, sharply pointed screw in appearance.
The key components of the aerator construction are: an electric drive motor, a fan, and an air duct pipe, also known as a lance.
The length of the lance varies depending on the aerator model and is usually in the range of 1m - 6m.
The large size of the pipe is because it is a part of the device that is "submerged" in the grain pile to a depth of several meters, while the air suction mechanism and motor remain above the surface of the grains.
The several-meter-long lance introduces air sucked in by the aerator to the lower layers of grains that do not have natural "access" to air. To fulfill this function, the walls of the lance are perforated - allowing air to escape evenly to the sides through small holes. The size of the aerator pipe holes should be small enough to prevent grains from the aerated pile from entering the inside of the air duct.
The lance also serves to move grains. For this purpose, it is equipped with a spiral, gutter-like thread. The electric drive motor rotates the lance inside the grain pile. This works similarly to the popular construction industry mixer. The rotation of the lance is fast; for example, for models like KOZAK, available on our website, it can reach 3000 rpm, which is 50 rotations per second. This keeps the grain in continuous motion, ensuring even drying.
Why it's worth using grain aerators
Using grain aerators is crucial because the aeration process improves grain quality, preventing the development of pathogenic microorganisms. Grain moisture above 14.5% favors the proliferation of mold, fungi, and bacteria, such as Aspergillus (Aflatoxin) and Fusarium, which can cause the formation of mycotoxins - substances harmful to both animals and humans.
In the years 1942-1943 in the USSR, hundreds of people died from consuming flour contaminated with mycotoxins. The toxic flour came from grains that remained in the fields over the winter, absorbing moisture and molding before harvest. The cause of this disaster was the Fusarium fungus and its production of trichothecenes. In a more recent past, it is worth mentioning a study carried out in Great Britain in 1982, where, responsible for the deaths of many Russians four decades earlier, trichothecenes were detected in over half of the sampled breakfast cereal.
It must also be noted that poisoning from mycotoxins resulting from improperly stored grain is not just a thing of the distant past. Cases of local epidemics are still recorded today, especially in less developed regions of the world.
Feed made from fungus-infected grains affects the fertility of farm animals and their overall health. This can directly impact the productivity of livestock.
Thanks to continuous ventilation using an aerator, the air delivered to the grain changes the microbiological conditions, limiting the development of these harmful microorganisms.
Aeration also affects the activity of enzymes in the grain, such as amylases and proteases, which are responsible for breaking down starch and proteins. As a result of aeration, these enzymes become more active, improving the nutritional properties of the grain and accelerating its metabolic processes. This action also aids the storage of grain because it improves its chemical stability and reduces the risk of deterioration in quality due to unwanted enzymatic reactions.
It is also worth emphasizing that the aeration process reduces the level of carbon dioxide, which in excess can promote the growth of anaerobic bacteria. These can cause fermentation and spoilage of the grain. Thanks to aerators, a stable oxygen level is maintained in the mass of the grain, allowing the health and quality of the crops to be preserved.
If you are interested in balanced feeding of farm animals and increasing the nutritional properties of feed, check out our article on feed production.
Summing up:
A grain aerator is a device that, despite its relatively low price, can prevent losses many times exceeding its cost. In this context, purchasing a high-quality aerator is a worthwhile investment. As I hope I have shown, fungi and bacteria developing in granaries are invisible saboteurs of our crops and a threat to the health of humans and animals.
Preventive use of aerators is a better way to combat fungi and bacteria than using chemical agents once they have developed.
(source: Mycotoxins - an invisible threat, Joanna Kurek, April 2022)
