On 01/06/2020 11:20, Tim Streater wrote:
On 01 Jun 2020 at 10:23:35 BST, Scott wrote:

In the old days we used to keep opened tins in the fridge. I think
you could even buy a plastic lid to fit on the tin. Now we are told
to transfer the contents to another container.

Has the construction of tins changed, or is this another example of
excess caution? I have never known a tin to start rusting in the
timescale involved and even if it did, the rust would be at the top
not were the food is.
The unopened tin contents will be sterile. The moment the tin is opened, the
decay process starts which produces some acid as a result, which will start
attacking the tin lining. The deay process is slowed by refridgeration, but
not stopped. I dunno what tins are lined with, but I wouldn't want to be
ingesting it, probably. So transfer it, unless you know that the contents will
be used later today or tomorrow.

I seem to recall that tins for naturally acidic stuff such as pineapple are
lined with something else, but I can't remember what. It prolly puts the cost
up slightly. Still, I expect Greg will be along soon to correct me.

some are lined with plastic, some with a metal compound.