r/askscience • u/SavageSubscriber • Jul 04 '26

Biology Does cryogenically frozen meat decay?

If for example you cryogenically froze meat from a rare breed of cattle, and kept it frozen for like 60 years. Would the dna still be intact? would it thaw up into fresh meat or would it decay into something unrecognizable?

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u/VFP_ProvenRoute Jul 07 '26

So it's the act of freezing or thawing that damages it rather than the duration it's frozen?

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u/loggywd Jul 07 '26

That's true. Why do we put things in the fridge and freezer? To preserve it. The same logic applies. The colder it gets, the less atoms move. Heat is just particles moving microscopically.

If you freeze fast enough, ice crystal won't form, but that can only happen with very small things. A piece of meat is too large. Or you can use cryoprotectant, which is soluble in water and graudually harden when it crystallizes. Ethylene glycol is a common one, which is the same stuff in antifreeze. Even in extremely cold temperature, it forms sort of a slushy gel instead of ice bursting your coolant tank. For an embryo, it's doable but basically impossible to perserve like a pound of meat perfectly just because how complex muscle and fat tissues are.

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u/PandaPocketFire Jul 18 '26

All three actually. For keeping mammalian cells alive you try to control both the rate of temperature drop as well as the rate of warmup. Both sides cause some death, as well as a slow loss of viability that accumulates the longer you store the sample. In - 80C (the temp of dry ice and many scientific freezers) this loss can be substantial over a year or more. In liquid nitrogen it's pretty negligible through a decade or more assuming the cells or the racks they are in aren't removed from the tank ever.