Empty the grain product into a large bowl as soon as you arrive home from the store.
Dig through the product with a spoon to check for evidence of grain moth infestation. Look for anything that doesn’t resemble the product itself, especially tiny clumps that may have bits of web stuck to them. You might also see odd lumps or tiny pieces of your grain product that look like they’ve been finely ground up.
Seal newly purchased material in a plastic food storage bag and return it to your retailer if you find signs of infestation. Discard the original packaging.
Portion product that isn't infested into plastic food storage bags. Press as much air as possible out of the bags and seal them tightly.
Put the sealed bags into a plastic container. Cap it tightly.
Freeze the plastic container for at least 72 hours.