How Long Do Whole-Leaf Hops Last?

I know that how long a given hop lasts depends on its stability and how it is stored. For example, I've read that centennials have poor stability, meaning that , they will not last as long as other types. I also know that if I expose them to light, air, warmer temps they will go bad faster.

However, just how long will my whole-leaf centennials last? Weeks? Months?

They are in a vacuum sealed pack from freshops.com, and they are in my freezer in the box they were shipped in.

I'd love it if anyone has a link to just how long centennials, in whole-leaf form stay good for. They are from this year's crop, btw. I also bought some chinook and some amarillo. I wonder how long those will last as well.

Final Question: How do you re-seal a vacuum sealed bag?

Some of my hops were shipped in a six ounce bag. I obviously do not want to use all six ounces at once. However, in the past, I've opened up a vacuum-sealed bag of simcoe and used it in the boil. I then sealed it as best I could, but couldn't figure out how to return it to a vacuum sealed environment. When I took them out after two weeks to dry hop, they had gone bad--I got that Parmesan cheese smell and they looked brown.

Simple answer...Not very long at my house.

They should be frozen and kept air tight bag

Reseal a vacuum sealed bag with a vacuum sealer.

Properly vacuum sealed and frozen, they should easily last a year or two. I've never kept hops longer than that, but they should last even longer than that.

I was thinking about this the other day. I have an ounce of Simcoe plugs from 2006 that have been in my fridge for a few years and I looked at them the other day and they seemed fine. I think I might use them for bittering...I think if kept in a vacuum sealed bag in the fridge/freezer they will last indefinitely. I don't think I'd use them for aroma though.