Maintaining canola quality in grain bags

Maintaining canola quality in grain bags

Canola acreage is up. Will you need to store some of your harvest in grain bags? Keep the quality high

Researchers from the University of Manitoba have recently published two studies on how canola fares when stored in grain bags for different periods of time. The research was done under Prairie weather conditions, funded by the Canola Council of Canada.

Grain bags, sometimes called silo bags, are marketed as temporary storage solutions for farmers who need extra storage space. Some may not have enough room for a bumper crop in their permanent bins. Others need extra storage to separate one crop from another. A silo bag can do those things, says Dr. Chella Vellaichamy, one of the University of Manitoba researchers that conducted the studies. Another reason farmers use grain bags is for in-field storage, says Vellaichamy, to make fieldwork more efficient.

Vellaichamy says that although the general belief is that grain bags are cheaper than more traditional grain storage, that’s not actually the case. When “you go through the cost-benefit analysis, it’s actually pretty similar in cost, there’s not much savings because these bags are one-use only. Next year you’ll have to buy new bags.” And, as you probably know, it’s not just the bags that you need to buy, it’s also the grain bag loader/unloader.

So what did Vellaichamy and his colleagues find about how well canola keeps in the silo bags? A lot of depends on the grain you’re putting into the bags. Dry canola can be stored for up to 10 months without any quality deterioration, says Vellaichamy. “That’s the maximum storage time for canola on a Canadian Prairie farm in a silo bag.” For canola stored at more than 10 per cent moisture, says Vellaichamy, caking due to moisture condensation can more easily damage grain; that damage can happen more quickly if the moisture content is higher than 12 per cent.

If it’s been a hot and dry summer, and you’re harvesting at the end of the season, the grain might be okay to go into the bag as is; if it’s been a wet season, you may have run your canola through the dryer before putting it in the bag to maintain high quality canola if you’re keep it there for a while.

If you plan to keep the grain in the silo bag for a very short term, three to four weeks maximum before you put it into a more permanent storage, then it’s OK to put it in the silo bag wet.

Generally, if you’re storing dry canola from October through April, it should maintain its quality. But when spring and summer come around and the temperature goes up, a quality issue could arise. Ambient temperature conditions impact grain stored in bags; the warmer it gets, the more deterioration can happen due to moisture migration and condensation.

If your canola is nine per cent moisture or less, you can store it for 10 months (until August). If you’re hovering at around 10 per cent moisture, you can store it for about seven months without deterioration (until April). Wet canola, 12 per cent moisture, should be taken out of the bag before the temperature starts to rise, that is, before winter ends (preferably the end of February).

With very wet canola, 14 per cent moisture, you’ll need to dry it within a month’s time. You’ll probably want to avoid summer storage altogether if the moisture content is high side and you want to maintain a Grade 1 or Grade 2 designation, says Vellaichamy.

Another thing Vellaichamy and his colleagues found over the two years is that the quality of the grain stored depends on the weather during the seasons during the year. “If it’s been a mild winter, not that cold, then you have to unload before the snow starts melting. If it’s been a really cold winter, you can probably unload up to three or four weeks later,” says Vellaichamy.

Continuous monitoring of the bags for damages due to birds, deer, and rodents is another important factor for success of this silo bag storage system.

Silo bag storage is always undergoing review for improvement. Vellaichamy says manufacturers have been testing the bags under different conditions and with different crops. They are also developing new, more airtight techniques to seal the bags, rather than using wooden 2×4’s to close the ends of the bags.

About the author

Dilia Narduzzi's recent articles



Stories from our other publications