Why does some frozen food puff up when defrosting?

I know freezing is supposed to make foods expand but it seems that two pre-packaged sealed food items that I have in my freezer seem a bit puffy (chicken curry and chicken dumplings with cabbage) after taking them out of the freezer.

I don't think they were that way when I bought them but not sure. My freezer seems to working well (although my fridge is a bit variable) and foods always seem well-frozen. And I only left them out less than half an hour.

Can sealed food packages expand when they defrost rather than the other way around? Thanks!

Best Answer

That's just the air in the package expanding, as it goes from freezer temperature to room temperature.

It sounds like you're thinking of the fact that water expands when it freezes (and shrinks when it melts) but that's not what's happening here. The air warms up long before the ice starts melting.

Some freezer packaging has small holes in it (or not so small holes, if you're unlucky), which prevents this from happening.

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What does it mean when frozen food bag puffed up?

Bacteria feed on the contents of the pouch and produce gas. Since this gas cannot escape from the sealed packet, it accumulates inside and causes the pouch to bloat.

Why is my frozen turkey package puffed up?

They told me: \u201cThe puffy appearance in our tray pack items is due to the fact that we use an innovative way of packaging called MAP (modified atmosphere packaging). MAP uses oxygen and nitrogen to help maintain the freshness of the product.\u201d

Which is the incorrect way to defrost frozen food?

Perishable foods should never be thawed on the counter, or in hot water and must not be left at room temperature for more than two hours.

Is it normal for ground turkey package puffed up?

\u201cFrom a visual perspective, if you have a piece of meat that's in a bag or vacuum-sealed pouch (and) if it has blown up like a balloon, it's going to be really rotten, so much so, you should not even open the bag,\u201d butcher James Peisker, co-founder of Porter Road, told TODAY Food.

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Images: Sebastian Coman Photography, Kindel Media, Artem Beliaikin, ROMAN ODINTSOV