Husked walnuts can be stored where temps or mosture are moderate.
Question: Could you please tell me if walnuts are still good after being left in the clean shell for a year. We picked them last year, husked them and left to dry for two weeks in the shell but have left them all year. We need to know if we should throw them out or shell them and use them. Your answer will make a big difference and be a great help. - Pam K.
Answer: Funny you asked that. I just threw away a bucket of walnuts that had been in my storage room since last season.
I was thinking that very same thing. Here was how I made my decision: my walnuts were stored in an outside shed exposed to both freezing, high temps and potential insect and disease infestation. I didn't even sample one and tossed the whole batch (along with the work I put into removing the husks).
You will probably be ok if you had them stored in a secure climate-controlled environment or had them frozen after they dried. Storage conditions and the time the nuts spends in that environment is important. A quick test would be to crack one and test by taste and smell. Any off flavors will be immediately noticed and the nuts should be discarded.
Husked Walnuts - Steve Nix Photo