Rendered turkey fat: how long will it keep?

Thanks, ChefOno. I appreciate your thoughtful, informative answers! I'll do the boil like you recommend, and then store the fat in the freezer.

The best answer I can give you is "maybe". It's not like Jewish women haven't been doing the same thing for thousands of years. But there is a small-but-not-zero-chance of trouble lurking at the bottom of the jar. So, to be perfectly safe, bring the fat up above 212F and hold it there for 10 minutes. Any water will boil off and any contaminants will be inactivated.

Or you could add some turkey or chicken skin and some onions and heat until well browned then strain the fat. The remaining bits are known as gribenes which can be served with latkes or a nice potato kugel. Hanukkah is only a week away after all.

In another direction, I think turkey and chicken fat make the best gravies for their respective meats, either straight or mixed 50-50 with butter.

Properly rendered... not sure. I poured all the pan drippings into a large measuring cup, and let it separate for a while (10 mins). Then I poured off the fat into a container and refrigerated it. Is that proper enough?

If the fat was properly rendered it should safe to use. Schmaltz you've got. Latkes maybe? If there's moisture and proteins mixed in with it (as from skimming stock) it's past its USDA-recommended lifespan. (Such a waste, such a waste!)

I used some of the fat to saute the veggies for my Turkey Soup.
The rest, I froze. Hope this helps.