Rancid Raw Nuts
Sometimes they are stored in the grocery store bulk bins for a long time. They may go rancid and moldy after a few months of sitting there.
After eating fresh nuts for a while, you will be able to pick out rancid nuts by their taste, texture, and appearance. I buy them from a local health food store and they usually look good.
Always store them in the refrigerator to keep them fresh and prevent mold.
Brazil nuts are harder to find fresh. I often find them rancid in the store. You can usually tell the difference in taste between fresh and rancid brazil nuts.
You could buy nuts / seeds on-line and they will usually be good. A couple years ago I purchased macadamia nuts on-line from a reputable store and they were all rancid. They had bugs and spider webs in the shells. I sent them back and received a full refund.
Another thing to consider is that nuts / seeds stored in bulk bins for a long time may have mold and yeast growing on them. This is usually the case with walnuts.
The mold can be killed by soaking the nuts / seeds in food grade hydrogen peroxide. Put one teaspoon of hydrogen peroxide in a bowl of fresh water. soak the walnuts in this for 10 to 15 minutes. Drain and rinse then continue soaking the walnuts in fresh water for the required time, 6 to 12 hours.
For on-line ordering, this is a great source of seeds:
(Gabriel Cousens says the golden flax and slightly more nutritious than the brown flax)
Green Pumpkin seeds
Raw Almond Butter