tinned food

[bekikia]

does tinned food ever go off and if so why is there a best before date on them??

[ursula62]

The food would eventually deteriorate, even though it is protected from oxygen, although this would take a long time.  "Best before dates" are there to ensure you eat the food in its optimum condition, unlike "use by dates" which have a legal standing.  

Some canned goods react with the metal can lining, particularly fruits in juice and items with acidic sauces, e.g. tomatoes. Also, these days they use plastic linings in some cans, and scientists believe that the plastics leach synthetic oestrogenic substances into the food. So over a long period of time the quality of the food will deteriorate, although even a use by date has to be well inside the time period before reaction with the can lining or plastic could become toxic. 

The basic rule of thumb is that the fresher a food is the better. Tinned foods are a good storecupboard standby but should not be relied upon as the only source of fruit and vegetables.

[cassimer]

Ursulas answer is great. Bear in mind that you should never buy or store dented tins as this can damage the internal linings which can make the food go off and be poisonous. Am always surprised how many supermarkets are willing to sell off dented tins cheaply.

[netibiza]

In Spain the dented tins are sold are normal - and they think you're strange if you ask for a non-dented one!

[dmsjps]

I don't know the answer to the question, but I do know that my mum-in-law used to have tins in her larder that were years old and in the days those tinned foods were manufactured (or even when I was young in the 60s and 70s) they didn't put a 'best before' date on them. She's a war child though, and they were taught never to throw anything away. We don't know what they went through. I could well see 'best before' dates being extended or even being made redundant if the same thing happens again.

 

I think the manufacturers just make the shelf life so short to cover themselves and minimise risks of anyone contracting food poisoning or whatever. After all, despite what the media says about us all being so healthy and strong these days compared to years ago, we seem to be a nation of allergy sufferers and people with weak immunity systems!

[GMH]

I would guess that tinned food would have an average lifespan of about two years.