While many farmers store distillers grains in a variety of ways, Hubbard Feeds' Dr. Simone Holt says some ways are better than others.

"What type of product you purchase and the number of cattle you're feeding will be the biggest indicators of how and where you store the distillers," Holt notes.

There are three basic types of distillers. Dry distillers grains have 90% dry matter. Modified distillers grains have 50% dry matter; and wet distillers grains have 35% dry matter.

"Spoilage can happen quite quickly as we get into the wetter products," Dr. Holt says.

There are three main storage methods that have proven effective for the various distiller products.
1. Storing dry product in a bin
2. Storing wet product in a bunker, commodity shed or on the ground in a pile
3. Ag bags, which are a method of sealed feed storage in a high quality polyethylene bag

Dry distillers or dry gluten can be relatively easy to store in a bin or in a commodity building that has some protection from the weather. Holt says the distillers will store well for a long period of time without any type of preservatives because of its low moisture content.

Modified and Wet distillers grains can be more of a challenge to store, especially in the summer, because of their higher moisture content.

"The shelf life of these products will run somewhere between three and five days piled on the ground without any molding occurring," Holt explains. "After that time we generally see some mold or spoilage starting to occur. In the winter these high moisture products will last a little longer; you can go out two weeks without problems with spoilage."

Holt recommends ag bags as another solution to long-term storage of co-products. There are a couple of ways to go about this. The modified distillers grain (50% DM) product can be stored in an ag bag quite easily. However, it does tend to flatten out a little because of the higher moisture content. You can expect to see 3% to 6% storage loss associated with using the ag bags.

"When storing Wet distillers grains (35%DM), we are seeing producers mixing this product with dry hay or straw and then bagging, because the wet product doesn't store very well by itself in an ag bag," Holt adds. "Wet distillers grains tend to break the bag because of the pressure from the bagging machines and the additional weight from the moisture. Mixing 10% to 15% straw or hay to make it a more substantial product to push into the bag helps. This combination will store fairly well for an indefinite amount of time. Once the bag is open you should take about a foot per-day off the face of the product. If not, you could encounter some spoilage around the face."

Long Term vs. Short Term Strategies

The best strategy for storage will again depend on the type of distillers grain to be stored.

"For the high moisture distillers products, ag bags and covered bunker silos are working very well for long-term storage," Holt says. "Short-term storage is going to be on the ground, or on a cement pad in a commodity building. You should get from five days to two weeks storage on the ground. That is compared to several months storage in bags or covered bunkers."

Holt says that producers have to take storage loss into account when calculating how much co-product to purchase and how much a distillers feeding program will cost.

Hold concludes, "You can estimate around 3% to 15% loss. Storage losses of up to 15% for wet distillers grains (35%DM) and 10% for modified distillers grains (50% DM). In an ag bag shrinkage will be around 3% to 6%."