Opened a tin of tuna last night. Tuna as I'm sure we all know is fish and fish is well known for going off very quickly. So why are the tins labelled "best before 2010"? I am well aware of the benefits of canning, but what other things do you have to do to give a bit of tuna a lifespan measured in years? well, it tastes good, so there can't be to much of a problem with whatever they do to the poor fish so I'll just have to carry on enjoying it.