I found this. I didn't know it should be refrigerated:

Nut and Alternative Flours

Like whole grain flours, nut and these alternative flours have high levels of oils, making them more subject to oxidation and rancidity.

• Types: Nut meals and flours (such as almond or hazelnut), coconut flour, wheat germ, rice bran, flaxseed meal, hemp seeds
• Storage: Refrigerator or freezer, preferably the freezer.
• Shelf Life: 6 months in the refrigerator, 12 months in the freezer
• Is It Still Good? The flour should smell sweet and nutty. If it tastes bitter, it's gone bad.