Spoilage of freeze-dried food

Factual Questions
1

Chuck Palahniuk’s most recent book involves as a major plot point some form of freeze-dried food. He doesn’t mention a brand (natch), so it’s probably easier to describe by just quoting the book

So, here’s my question (and hopefully this won’t give anything away): if you opened the bag of such food, how long would it take for the contents to spoil? I mean, sure it wouldn’t last as long as it was originally supposed to, but this sounds pretty similar to cup-o-noodles and that seems to last months without going bad. Would it depend how long the stuff had been in the bag so far?

2

It would depend a lot on the ambient mositure I’m assuming. Freeze dried foods are preserved because theyre dry. Once they soak up enough water from the air to start turning moist, then they’ll start to decompose.

Then again, conventionally dried foods like jerky keep perfectly fine in the open. Perhaps the water affinity of the food would also be a factor.

3

Yes, it all depends on how dry the food remains.

If it gets thoroughly wet, it goes bad as quickly as any other soup, stew, or similar food.

If it gets damp, it gets moldly. Or full of mildew.

But if opened and kept dry it should remain OK for several days, maybe a week. Dry and cold will last longer than hot and humid.

There there is the vermin problem - once it’s opened you have to worry about rats, mice, bugs, raccoons…

4

Huh. I’m surprised that cup-o-noodles cups are well enough sealed that they push the time from a week to months. At least, I’ve eaten some I’m sure were kicking around in the pantry for that long with no ill effects.

5

As long as the seal is sufficient to keep moisture and vermin out, it greatly extends the life of the food inside. I’m sure you could open a cup o’ noodles type package and, if kept in a truly dry and bug-free, rodent-free place it would continue to remain edible for long periods of time. Or if you poured it into a ziplock baggie and sealed that. The uncertainty comes in when you can’t be sure of moisture exposure or what may have been nibbling on it or lay eggs in it.

6

When I was young, I learned a lesson in ambient humidity. Having grown up in Michigan (humid in the summer), it was always important to seal up the Doritos, 'tater chip, or Cheetos bag really, really well or they’d go stale really, really fast. They wouldn’t get soggy or anything, but just go stale. One time in Reno (dry, arid place) we’d left the car in valet parking at the Circus Circus for a week. We’d had a bag of Doritos in the car for the trip from Vegas. My dad was pleased to see the bag for the trip bag to Vegas. I remarked that they’d certainly be stale, but he gave me one and it was absolutely perfect, due to the lack of humidity.

May seem perfectly obvious now, but I grew up, too, right?

7

Broomstick

"There there is the vermin problem - once it’s opened you have to worry about rats, mice, bugs, raccoons… "

Bwahaha, erm hahaha. ahem erm ok.

I don’t know how much camping you’ve done, but I can assure you, rats and their brethern can smell food through a mylar bag.

8

I don’t know about the cup kind, but I’ve had packets of Ramen that I’ve found small holes[sup]*[/sup] in, that still tasted fine, after probably being in my cupboard for a month or two. Montana is pretty dry, though, so that may be a factor.

And there are some freeze-dried foods that taste bad enough that I don’t think spoiling could make them any worse… I still occasionally have nightmares about freeze-dried enchiladas.
*not vermin-chewed type holes, just the seam coming apart a bit

9

Yeah, but they can smell it better when there’s a hole in the bag. And a hole in the bag can frequently indicate critters have been at the food.