Ground flaxseed (flaxmeal): Ground flax is subject to spoilage from light and heat, due to its oil being released from its protective coating during the grinding process. Therefore it is ideal to grind just the amount you need at the time it is needed. If you grind more than that, store the unused portion in a covered container in the freezer.
Packaged ground flax (flaxmeal): To maintain high quality and freshness, store ground flax in the refrigerator or freezer. Some packages will have a “best before” date to help guide you. In these cases, follow the food manufacturer’s suggested guidelines for safe storage.