How to know if my walnuts are fresh enough to be good to eat?

I have some walnuts which were picked up from under a local tree, left to dry for a while, and shelled. They look moderately old, but haven't become shriveled or gone moldy. Some have a kind of bitter after taste when eaten raw (unpeeled). Does this mean they are too old, or is it normal?

Will they have the same flavour when cooked?

I'm not sure whether I should cook something with them, or whether I should discard them.

storage-lifetime nuts

Best Answer

Your best methods are to use the tools nature gave you:

Visually inspect the nutmeats; you should not see signs of mold or discoloration
Smell the nuts; they should not have that rancid odor, nor (according to Eat by Date) smell like paint
Feel their weight; they should not feel light or dried out, nor slimy or wet (although the latter is very unlikely unless they have been stored in wet or very humid conditions)

None of these are absolute, but together they give you the best indication that you can probably get at home.

I found several anecdotal accounts that the float test, also described by MaxS (the nuts should float in water) will help separate bad nuts, but I could not find credible documentation.