Which nuts and seeds need to be stored in the fridge/freezer?
So I've always heard that the freezer or fridge is the best place to store nuts so they don't go rancid or stale. I've learned this the hard way with flax seeds, but I keep all of my other nuts and seeds in airtight mason jars in a cabinet, and haven't had much of a problem. I generally use most of them within a few months, and I like my current method because I have a very small fridge and freezer, so the space is at a premium. That said, I realize there are probably certain nuts/seeds that go stale or rancid more quickly and I'm thinking I should selectively leave some in the cabinet and others store in the fridge/freezer. Looking for advice as to which ones would be best kept in the fridge/freezer vs. the cabinet. Thoughts?
Nuts/seeds I typically have are: walnuts, almonds, pecans, pepitas, sunflower seeds, pistachios, hazelnuts, peanuts, cashews.
Several factors contribute to the shelf life of nuts & seeds:
The less saturated a fat, the more perishable it is - so nuts that are high in PUFAs (e.g. walnuts & pecans) will turn rancid most quickly.
Shelled nuts or seeds have a shorter shelf life than those still in the shell.
Heat accelerates spoilage via oxidation, so roasted nuts and seeds turn rancid more quickly than raw ones do. Exposure to light also causes oxidation - the darker the storage space and container, the better.
Humid conditions or excess moisture will encourage spoilage, so dry storage is best. If you keep them in the fridge, use one of the produce drawers set at the lowest humidity level.
Of everything you listed the walnuts, pecans and sunflower seeds are the most perishable. And FYI, *whole* flax seed won't spoil nearly as quickly as pre-ground flax meal, so always buy the seeds and grind them yourself as needed.
My experience with nuts in a hot, humid climate -
Anything ground or flaked needs to go in the freezer immediately - it goes moldy really quickly, and is hard to tell by looking at it. Almonds and shelled pumpkin seeds last pretty well, but not indefinitely. Cashews, walnuts and pine nuts go in the freezer.