Author Topic: How long do opened cans last?  (Read 880 times)

Offline Gamer

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How long do opened cans last?
« on: March 28, 2020, 02:47:37 PM »
I've been buying various kinds of tinned food (minced beef/ irish stew/ corned beef/ veg soup/ stewed steak/ ham/ fruit etc) and am impressed to see that their "best before" dates are up to 2 years or more in the future.
Question- Suppose I open a can now and only eat half of it, how long will the other half keep, or will it start to go bad within days now that the tin has been opened? 

Offline mountainmoma

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Re: How long do opened cans last?
« Reply #1 on: March 28, 2020, 04:21:23 PM »
once a can or pouch of wet food or a "brick" aseptic package of milk or juice is opened, it then needs to be treated the same as any other non-packaged food of its type.  The food does not have preservatives in it ( well, not usually) so once it is opened, its protection from germs and oxygen has been breached.

So, if it is a meat product, treat it like you would any other cooked meat product.  Which means a short time unrefrigerated. 

Canned beans are treated like any beans you have cooked from dried beans on the stove.  If you bring beans to a boil, with a lid on, and then leave untouched with the lid on, you can do without refrigeration by bringing it back to a boil each day before leaving it there safely lidded.  Other products may be similar, but personally I dont mess with things that could grow botulism ( meat, vegetables) A vegetarian bean chili with just beans, tomatoes and spices, for example, cannot grow botulism. 

I would use aseptic ( brick) packed milk that day if I did not have refrigeration, or make yogurt with it, etc...

If you have a refrigerator, store leftovers out of the can in a different container.  Usualy use within half a week, sometimes a week.  Again, beans get weird, so heat those up after 2 or 3 days, to a boil, then put back in the refrigerator. Canned peaches can keep all week in the refrigerator.  Canned meats, I dont know, spam should be the same as bologna or lunch meat or left over meat, so go by your experience with those.

Offline Gamer

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Re: How long do opened cans last?
« Reply #2 on: March 28, 2020, 05:36:49 PM »
......If you have a refrigerator, store leftovers out of the can in a different container.  Usualy use within half a week, sometimes a week....


Thanks moma, reason I asked is because as a single dood living alone I usually find there's too much for me in a standard 6-inch can, as half is quite sufficient, so I wish manufacturers would put their stuff in smaller cans..:)

Offline Greekman

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Re: How long do opened cans last?
« Reply #3 on: March 29, 2020, 01:32:24 AM »
I trick we do with canned tomato paste is to level the paste mass and add a thin layer of oil on top. that will hinder fungi growth.
I guess you can try the same if you like your food a bit fatty/oily

Offline Gamer

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Re: How long do opened cans last?
« Reply #4 on: March 30, 2020, 07:57:31 AM »
Thanks people, and incidentally will unopened canned food last longer if we keep the cans in the fridge?

Offline mountainmoma

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Re: How long do opened cans last?
« Reply #5 on: March 30, 2020, 10:19:29 AM »
Thanks people, and incidentally will unopened canned food last longer if we keep the cans in the fridge?

no.  dont do that, the moisture could rust them.  Unopened cans can just be kept at room temperature. But, if you have a cooler place ( not cold like your refrigerator) that is even better. 

Offline richardr

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Re: How long do opened cans last?
« Reply #6 on: April 06, 2020, 05:24:53 PM »
most canned goods, 12-160z cans are about 220-280cals. Ought to be easy to hit that twice to use it up, in less than a week. Waste not, want not.

Offline Stwood

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Re: How long do opened cans last?
« Reply #7 on: April 11, 2020, 08:50:53 AM »
most canned goods, 12-160z cans are about 220-280cals. Ought to be easy to hit that twice to use it up, in less than a week. Waste not, want not.

I agree. We try and use it up within a couple of days.
If it happens to get shoved to the back and hidden..............well......

Offline Gamer

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Re: How long do opened cans last?
« Reply #8 on: April 11, 2020, 12:17:35 PM »
Thanks everybody, and another thing- Would powdered milk (or whatever it's called) be a good substitute if proper liquid milk becomes unavailable for whatever reason?
I mean, our bodies are supposed to need the calcium in milk, so is there calcium in the powdered stuff?
And what's the shelf life of cans of powdered milk, weeks, months, years?

Offline Stwood

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Re: How long do opened cans last?
« Reply #9 on: April 11, 2020, 12:28:50 PM »
Augason Farms country fresh milk (LT) has a 20 year shelf life.

I would say grocery store powdered is probably a couple years. We do not buy the grocery variety so don't really know.

Powdered is not going to taste like your regular milk, but will do as it's supposed to. It is good for using in baking.

Offline mountainmoma

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Re: How long do opened cans last?
« Reply #10 on: April 11, 2020, 01:57:11 PM »
Thanks everybody, and another thing- Would powdered milk (or whatever it's called) be a good substitute if proper liquid milk becomes unavailable for whatever reason?
I mean, our bodies are supposed to need the calcium in milk, so is there calcium in the powdered stuff?
And what's the shelf life of cans of powdered milk, weeks, months, years?

The powdered stuff has calcium, but so does kale.  The high nutrition, dark green veggies like kale are good sources.

I like to keep a small amount of good, full fat powdered milk on hand for short term disruptions, as milk for my tea is very important to my state of mind. This type of powdered milk does not last that long, about 2 years.  I forget.  You can go a few months after its date if you store in a place that deosnt get very warm, like anything else.  This milk tastes very close to regular milk.  When it hits its due date, I put it where I can remember to just start using it, for tea, on cereal, etc.... or I take it camping or make hot chocolate mix, nothing like full-fat dry milk for a great hot cocoa mix, you do not need much sugar with full fat milk, the dry milk then cocoa powder, pre mix in a quart jar in the kitchen in the winter time, that is my usual method to rotate it.  I only have a few cans of the milk in the pantry, every winter one or two are rotated into hot cocoa mix.  I have given hot cocoa mix as part of Christmas surprises for my neices, so it is easy lets say, have 4 cans, every December rotate 2 out to hot cocoa, buy 2 more, so there is always 4 in the pantry.

Peak milk is one of the good, full fat ones that is instant and mixes easy.  Nestle also makes one.
If you want to keep alot of milk, and not rotate, you need to get what Stwood talks about, the non-fat milk packed for 30 years.

Offline LvsChant

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Re: How long do opened cans last?
« Reply #11 on: April 11, 2020, 02:27:42 PM »
The nonfat powdered milk will keep a bit longer that the full-fat dry milk and will certainly be a good substitute if you cannot get fresh milk.

I'd also recommend storing the Parmalat (box milk) on the shelf. Doesn't require refrigeration and lasts a good long while... I have several cartons of that (whole milk is what we prefer) on the shelf.

There are various types of powdered milk and they do have varying storage life... I bought some from the LDS warehouse and canned it up in the #10 cans and it has a 20 year shelf life. I think you would get a similar life in mylar and buckets. Even the plain old powdered milk in the store should store for quite awhile. And if you use it as a part of your normal cooking, you can rotate the stock easily.

I use powdered milk in the winter to make my own hot cocoa mix and also have several bread recipes that call for powdered milk, so even without ever reconstituting it, I can use quite a bit.

Offline borderbill

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Re: How long do opened cans last?
« Reply #12 on: April 20, 2020, 02:36:52 PM »
I started dippin' into my stored goods. Had some SPAM (who doesn't) with best by date of 2015.  Admit it-you do also.  Mine was delightful- without any annoying unusual fragrances.  I give "old" goods the suspicious eye and aroma test- if it's OK, I devour it.  I am the suspicious sort, (had dysentery in the RVN)  but find that if there's no container rust, swelling, or other problems it's probbly OK.  Others here have made useful comments in re" best by" dates.  As in life- yer mileage may (and will) vary.

Offline LvsChant

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Re: How long do opened cans last?
« Reply #13 on: April 21, 2020, 05:52:00 PM »
Glad to hear it, borderbill. We actually have not been in the habit of storing spam over the years, but have bought some in the last few months. I'm thinking it may be a nice source of protein in a convenient shelf-stable can for the coming months. I loved spam as a kid... got to crack into a can soon.

I also typically consider those "best by" dates as a suggestion -- not an absolute :)