Frozen can safety


I have cans (most likely glass cans) stocked in a barn. During winter temperatures may sometimes become negative, leading freezing/thawing.

Since the cans are not altered, it is safe for me to consume the contents ?

I assume that this is not a problem given that, for example during transport, canned goods can undergo the same constraints.


Best Answer

It is possible that expansion of the contents caused by freezing could compromise canning jars' seals. I would expect most jars to break before this happened but a wide-mouth jar with a minimal shoulder might be streamlined enough to allow it if there were very little headspace.

As with all home-canned food, you should check the vacuum seal before opening and consuming. Do not consume cans which are not still under vacuum. Beyond that (and beyond the obvious risk of broken glass), freeze/thaw cycles do not present a safety risk.