Why is grain cleaning before storage a must?

Imagine an elevator where silos are filled with a mixture of different-sized grains, dirt impurities, ear fragments, and even mold spores. It doesn’t create any positive impression—although the batch may still look marketable from the outside, inside, processes of self-heating, microorganism growth, and mechanical friction between grains have already begun. Be sure that within just a few weeks, this mixture will turn into losses for your farm.

The reason is that high moisture will create thermal «pockets», mold will produce mycotoxins, and fine seeds and debris will block ventilation channels. How can this be avoided? The only practical solution is to clean the harvest before it reaches the silo.

First Line of Defense: Physiological Dormancy of Grain

Remember that grain is a living organism that breathes and emits heat. The more damaged or immature kernels in the batch, the more intense the respiration—and thus, the faster the temperature rises inside the mass, which has a devastating effect on grain quality.

Furthermore, the entry of green impurities only accelerates this process, as cellular sap activates bacteria that release additional moisture. Cleaning and calibrating the grain remove a significant amount of «stress material», allowing the commodity mass to transition into a state of physiological dormancy. This way, you can store grain without heating for up to a year in some cases.

The Importance of Minimizing Weight and Quality Losses

During long-term storage, grain naturally loses part of its weight through moisture evaporation and various respiration processes. However, uncleaned mixtures «lose weight» faster because organic debris and dust absorb and retain moisture, stimulating fungal growth.

Once mycelium starts growing, the batch not only loses weight but also its appeal to buyers: acidity rises, a musty smell appears, and visible spots form. After primary aerodynamic cleaning, the share of impurities drops below one percent, minimizing losses and directly improving product value.

How to Block Mycotoxins at the Start

Aflatoxin, vomitoxin, ergot, and other poisons do not form spontaneously—they require infected kernels and high humidity.

Aerodynamic cleaning operates on the principle of density differences: light, porous, or fungus-damaged grains separate along with husks and dust.

Experience in North Dakota showed that after such treatment, vomitoxin levels halved, allowing durum wheat to be sold at double the price. Thus, cleaning becomes the cheapest way to prevent mycotoxin contamination and protect your reputation as a high-quality agricultural supplier.

Energy Savings During Drying

It’s no secret that even the most modern gas or biofuel dryers cannot work efficiently if air moves through layers of dust and husks. Impurities create thermal resistance, forcing the operator to raise the temperature, burn more fuel, and risk «roasting» the top grain layers.

The cleaner the grain, the more evenly heat passes through, meaning lower temperatures and shorter drying cycles.

Ultimately, farmers save up to 20% of energy resources per ton and produce grain free from scorched embryos.

Not sure which grain cleaner is right for you?

Contact us now for expert advice and find out how you can improve your grain quality and market value with Metra.

Safe Operation of Elevator Equipment

Screw conveyors, elevators, and aeration fans are designed for specific density and granularity.

When straw or clods of soil are abundant in the flow, mechanisms wear out much faster: belts slip, bearings overheat, and fan blades clog with dust.

Timely cleaning of grain mass doubles equipment lifespan and reduces emergency downtimes during the critical shipping season when every hour affects company profits.

Additional Margin from International Sales

The basic price difference between feed and food-grade grain is about 20–40%, and the premium for seed fractions can reach up to 60%.

If your farm has its own grain cleaning line, you’ll not only raise the grain’s grade but also divide it into several commodity fractions—seed, food, and feed.

This segmentation increases stock liquidity, allowing you to sell one part immediately and hold the rest for a more profitable time.

The Role of Aerodynamic Grain Dryers in This System

Aerodynamic grain dryers combine two critical stages—final drying and finishing cleaning — in a single cycle.

A warm air stream lifts the grain, separates light impurities, partially «washes» the dust away, and simultaneously reduces moisture to a safe level for storage.

The absence of sieves and moving grates guarantees that the equipment won’t fail at the most crucial moment.

Among the key advantages of such equipment, the following stand out:

• Energy Efficiency. For example, the ADS-200 model consumes less than 1 horsepower and processes 200 bushels/hour, which is 25–30% lower energy consumption than traditional tower dryers.
• Crop Versatility. Switching from corn to rye or from millet to lentils takes only a few minutes.
• High Payback. In years of wet autumns, the price difference between raw and conditioned grain can offset the investment within just two or three days of continuous operation.
• Reliability. The average service life of an aerodynamic dryer exceeds 30 years.
• Thus, grain cleaning before storage and the use of aerodynamic dryers work in tandem: the first prevents losses, while the second brings the grain to perfect condition with minimal energy and time expenditures.