Can Grain Be Cleaned? What Grain Cleaning Can (and Can't) Fix
By Loraas Custom Sorting
One of the first questions we hear on the phone is also one of the hardest to answer.
"Can you clean this grain?"
It's a fair question—but before we can answer it, we usually have to ask a few questions of our own.
What crop is it?
What's in the grain?
How much grain are we talking about?
What market is it going to?
Those questions matter because no two grain lots are exactly alike.
A load of wheat with ergot is a completely different challenge than soybeans with volunteer corn. Corn containing excess fines requires a different solution than sunflowers contaminated with fertilizer. A food-grade processor may have much tighter quality specifications than a local feed mill.
That's why grain cleaning isn't about running grain through one machine and hoping for the best. It's about understanding the problem first, then choosing the right combination of equipment to solve it.
After years of working with producers, elevators, seed companies, and processors throughout the Midwest, we've learned one simple truth:
Grain cleaning doesn't create quality—it reveals it.
It removes material you don't want so the grain you do want has a chance to meet the market you're selling into.
The Biggest Misconception About Grain Cleaning
Let's clear up the biggest misconception right away.
Grain cleaning does not repair grain.
It doesn't heal cracked kernels.
It doesn't reverse mold damage.
It doesn't increase protein.
It doesn't add test weight to an individual kernel.
It doesn't improve germination in damaged seed.
Instead, grain cleaning separates.
Think about cleaning grain like sorting apples.
If you have a basket with 100 apples and 10 are rotten, you can't make the rotten apples fresh again.
What you can do is remove the bad apples so the remaining 90 are cleaner, more uniform, and better suited for the customer buying them.
That's exactly what grain conditioning equipment is designed to do.
Every Grain Problem Is Different
One of the reasons we ask so many questions before quoting a job is because contamination comes in many forms.
We've received calls about:
Excess foreign material after harvest.
Fertilizer contamination from hopper-bottom trailers.
Wheat containing ergot.
Corn with excessive broken kernels.
Soybeans mixed with volunteer corn.
Food-grade crops that failed buyer specifications.
Seed lots requiring additional conditioning.
Weather-damaged grain.
Grain contaminated with plastic or other foreign objects.
Each of those situations requires a different approach.
Sometimes a simple screen cleaner solves the problem.
Other times, gravity separation or optical color sorting is necessary.
And occasionally, we have to tell a customer something they weren't hoping to hear:
Grain cleaning isn't going to solve this one.
Honesty matters, especially when you're dealing with someone's crop.
What Can a Screen Cleaner Remove?
Screen cleaners are the foundation of nearly every grain conditioning system.
They separate material based primarily on size.
If something is larger or smaller than the grain you're trying to keep, there's a good chance a properly selected screen can remove it.
Screen cleaners commonly remove:
Weed seeds
Stalks and stems
Chaff
Corn cobs
Pod material
Dirt
Small stones
Excess fines
Broken kernels
Oversized foreign material
Think of screens as the first line of defense.
They quickly remove a large percentage of unwanted material before grain moves to more specialized equipment.
Choosing the right screen is critical. A screen that's too aggressive may remove good grain along with the trash. A screen that's too large may leave contaminants behind. Experience makes a difference.
What Does Aspiration Remove?
If you've ever watched grain being cleaned and seen dust swirling through the air, you've seen aspiration at work.
Aspiration uses carefully controlled airflow instead of screens.
As grain falls through an air column, lighter materials are carried away while heavier grain continues through the system.
An aspirator can remove:
Dust
Chaff
Empty hulls
Light plant material
Fine debris
Lightweight contaminants
This not only improves grain quality but also helps reduce dust around the worksite and improves the efficiency of equipment farther down the processing line.
What Can a Gravity Table Do?
Here's something many people don't realize.
Not all kernels weigh the same.
Even kernels that look almost identical can have very different densities.
A gravity table separates grain by weight and density, allowing operators to remove:
Immature kernels
Lightweight grain
Weather-damaged kernels
Some insect-damaged grain
Low-vigor seed
Poorly filled kernels
Gravity tables are widely used in seed conditioning because denser seed is often associated with stronger planting performance. They're also valuable in food-grade applications where a more uniform product is required.
What Makes Optical Color Sorting Different?
This is where modern grain conditioning takes a big leap forward.
A screen can't see color.
A gravity table can't recognize mold.
An aspirator doesn't know the difference between a healthy kernel and one that's discolored.
An optical color sorter can.
High-speed cameras inspect every individual kernel as it passes through the machine. The system compares each kernel to programmed quality standards and, if necessary, uses a precise burst of compressed air to remove it from the product stream.
Depending on the crop and the application, optical sorting may help remove:
Ergot
Mold-damaged kernels
Sprouted grain
Stained kernels
Off-color seed
Foreign crop seed
Plastic fragments
Glass fragments
Insect-damaged kernels
Burned or dark kernels
No two grain lots are alike, so machine settings are adjusted for the specific quality goals of each project.
One of the Most Common Calls We Receive: Fertilizer in Grain
Not every contamination problem starts in the field.
One of the most common emergency calls we receive sounds something like this:
"We accidentally got fertilizer mixed into our wheat. Can you help?"
Sometimes the source is a hopper-bottom trailer that hauled fertilizer in the spring before hauling grain in the fall.
Other times it's a grain cart, portable auger, conveyor, or even a grain bin that was used to temporarily store fertilizer.
The equipment may look clean.
Unfortunately, fertilizer has a habit of hiding in places you can't easily see.
A few prills tucked into a corner, under a cross member, or inside a trap door can end up in the very first truckload of grain.
That small amount of contamination can create a big problem.
We've helped customers work through situations like these, but they're also a reminder that prevention is almost always easier than cleanup.
Before switching any equipment back to grain, take the time to inspect corners, seams, clean-out doors, trap doors, unload systems, and structural ledges where fertilizer can collect.
Those extra few minutes may save thousands of dollars later.
What Grain Cleaning Cannot Fix
This is probably the most important section in this entire article.
No matter how advanced the equipment is, there are some things that simply cannot be repaired after harvest.
Grain cleaning cannot:
Increase protein content.
Increase oil content.
Repair cracked kernels.
Reverse heat damage.
Restore frost-damaged grain.
Improve germination in dead seed.
Remove internal disease that cannot be physically separated.
Undo weather damage that affects every kernel.
If every kernel in the grain lot has the same problem, there may be nothing for the equipment to separate.
That's why understanding the nature of the problem comes first.
When Does Grain Cleaning Make Financial Sense?
This is one of the first conversations we have with customers.
Just because grain can be cleaned doesn't always mean it should be.
Let's say an elevator is discounting grain by $0.04 per bushel.
If cleaning costs more than the value recovered, it probably doesn't make economic sense.
On the other hand, imagine a food-grade wheat contract where the grain narrowly misses the buyer's specifications because of ergot or foreign material. If conditioning allows that grain to qualify for the premium market, the value gained may far exceed the cost of cleaning.
Every situation is different.
That's why we encourage customers to evaluate the economics before moving forward. Our goal isn't simply to clean grain—it's to help customers make informed decisions that improve their bottom line.
The Right Equipment for the Right Problem
One of the biggest mistakes people make is assuming one machine can solve every issue.
In reality, successful grain conditioning often involves several pieces of equipment working together.
Screens remove oversized and undersized material.
Aspiration removes lightweight debris.
Gravity tables separate by density.
Optical sorters remove visual defects.
Each machine has a purpose, and understanding those differences is the key to producing the highest-quality grain possible.
Good Grain In. Better Grain Out.
Every grain lot tells a story.
Sometimes it's the story of a difficult growing season. Sometimes it's a story of an unexpected contamination problem. Sometimes it's simply the challenge of meeting a buyer's specifications in an increasingly demanding marketplace.
At Loraas Custom Sorting, we've learned that the best results come from asking questions first, understanding the grain, and recommending the right solution—not the most expensive one.
Sometimes that solution is a simple screen cleaner.
Sometimes it's optical color sorting.
Sometimes it's a combination of multiple conditioning steps.
And sometimes, the most honest answer we can give is that grain cleaning isn't the right answer.
We believe that's what a good partner should do.
If you're unsure whether your grain can be cleaned, give us a call. We'll ask the right questions, explain your options, and help you determine the most practical path forward.
Because every bushel has a story—and every bushel deserves the opportunity to reach its highest value.