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Old 10-15-2009, 05:53 PM
StarGaiz StarGaiz is offline
Join Date: Oct 2009
How long are canned Black Beans good (unopened)?

I have 2 cans of black beans purchased in 2007, and they have no expiration date printed on them, but I want to make some with our tacos tonight...anybody know if they should last this long? I didn't want to open them before I knew...and I wouldn't know the signs anyway.

Thanks for your time and help, replies as soon as possible would be awesome!
Happy Thursday night!
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Old 10-15-2009, 07:04 PM
HongKongFooey HongKongFooey is offline
Join Date: Mar 2008
2-5 years.
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Old 10-15-2009, 08:12 PM
raindrop raindrop is offline
Join Date: Oct 2008
One problem with cans that don't have an expiration date is you don't know how old they were before you bought them. IOW don't just go by how long you've had them. Still examine the cans for any signs of bulging, rust, or leaking. The top and bottom should be very flat, or even slightly indented, to indicate the vacuum seal is still good. Pay special attention to the seams at top, side, and bottom. I've had some cans that looked fine, but on closer inspection were showing very minuscule amounts of rust on seams. I threw them out.

Last edited by raindrop; 10-15-2009 at 08:14 PM..
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Old 10-16-2009, 10:56 AM
janeslogin janeslogin is offline
Join Date: Aug 2008
We ate some this week about 72 hours ago that were purchased sometime before 1994 and have not gotten sick yet.

Last edited by janeslogin; 10-16-2009 at 10:57 AM..
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Old 10-16-2009, 03:51 PM
raindrop raindrop is offline
Join Date: Oct 2008
Janeslogin, so those cans of beans were more than 15 years old??? Yikes!!

I absolutely lurve black beans, but I have an EXTREMELY sensitive digestive system. There's just no way I would ever attempt something that. (And that's also why I'm hesitant to eat at other peoples' houses. [shudder]) Even if my cans don't show any signs of compromise they still get tossed after 2 years.

Coincidentally I simmered a pot of black bean soup yesterday even before reading this thread, (and had the leftovers for breakfast this morning, yum). After cooking my own from the dried form the beans from the can just don't seem to measure up. But I still do keep a couple of cans as emergency backup.
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Old 10-17-2009, 03:43 PM
Markxxx Markxxx is offline
Join Date: Apr 1999
Location: Chicago,IL
Posts: 14,962
I had a whole bunch of canned goods, I put away after 9-11 and the government said to make a stock. I had forgotten about it, but last summer I found them and ate them. So they were at least 7 years old. No problems at all. None of the cans looked deformed and the canned goods (veggies and beans and fruit) all tasted fine.

Heck I had sealed boxes of cornbread mix, I mixed it up and ate it. It tasted fine. Of course now I have nothing in my food reserve
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Old 10-17-2009, 04:08 PM
Spoke Spoke is offline
Join Date: Dec 1999
Yeah, you'd be amazed how long canned goods will keep. I once ate some 15-year-old green beans with no ill effect. (And they were delicious!)
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Old 10-17-2009, 04:39 PM
Staale Nordlie Staale Nordlie is offline
Join Date: May 2003
Properly canned food is supposed to last pretty much indefinitely as long as the can isn't damaged.

Example :
The steamboat Bertrand was heavily laden with provisions when it set out on
the Missouri River in 1865, destined for the gold mining camps in Fort
Benton, Mont. The boat snagged and swamped under the weight, sinking to the
bottom of the river. It was found a century later, under 30 feet of silt a
little north of Omaha, Neb.

Among the canned food items retrieved from the Bertrand in 1968 were brandied
peaches, oysters, plum tomatoes, honey, and mixed vegetables. In 1974,
chemists at the National Food Processors Association (NFPA) analyzed the
products for bacterial contamination and nutrient value. Although the food
had lost its fresh smell and appearance, the NFPA chemists detected no
microbial growth and determined that the foods were as safe to eat as they
had been when canned more than 100 years earlier
More on old food: .
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Old 10-18-2009, 03:23 AM
The Second Stone The Second Stone is offline
Join Date: May 2008
Location: Antioch
Posts: 11,459
Canned goods in undamaged cans should be good indefinitely. As in many, many years. I have noticed that years old tuna fish in cans gives me diarrhea, and I've heard that acidic stuff like tomato juice will go flat. Black beans I'd be fine with for at least 5 years.
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Old 10-19-2009, 08:14 PM
raindrop raindrop is offline
Join Date: Oct 2008
That's an interesting article about the canned goods from the sunken steamboat. Also interesting is that further down in that same link it mentions that the seams of cans used to be soldered with lead. But nowadays most seams are welded, sans the lead.
In the traditional three-piece cans, a welded side seam has replaced the lead-soldered side seam in all but 3.7 percent of American cans, says NFPA official Roger Coleman. The welding process uses electrodes that apply pressure and electric current to overlapping edges at the side seam. These new seams eliminate concern about lead leaching into metal canned foods. In the 3.7 percent of U.S. cans where lead still is used, it is often for dry foods (such as coffee) packaged in cans, according to Coleman. Leaching is not a concern here.
So I wonder if the scientists who checked the cans from the sunken ship also tested for lead? And I also wonder when did lead soldered seams stop being widely used in the U.S.? 10 years? 20 or 30 years? When you use the very old cans how likely are you to encounter lead seams?

Also interesting to note that...
Many imported cans, however, still bear lead-soldered side seams. To tell whether a can has been soldered with lead, first peel back the label to expose the seam. The edges along the joint of a lead-soldered seam will be folded over. Silver-gray metal will be smeared on the outside of the seam. A welded seam is flat, with a thin, dark, sharply defined line along the joint.
Since I often shop at an "international" store, I find this helpful.

Also, cans are definitely NOT good for indefinite periods, especially those which contain acidic foods, e.g. tomato sauce, fruit juices, etc. Perhaps there's something about being at the bottom of a river that helps maintain the vacuum seal, but I've personally thrown out many old cans that were visibly leaking and bulging, so I can't accept that they are okay for indefinite periods.

Foods with a naturally high acid content--such as tomatoes, citrus juices, pears, and other fruits--will not support the growth of food poisoning bacteria.
Interestingly the article mentions that acidic foods don't support bacterial growth, but it's also interesting that IME canned acidic foods are often the first ones to go bad in other ways. I think acid eats away at soldered seams?

I've also had glass jars of fruit juices whose metal lids had lost their vacuum seal, bulging at the lid. Ever notice that warning on the lid to alert you if the button is popped up? Yes, I've had a few "pop" up while sitting too-long (i.e. 2 years) in my basement. And out of curiosity I opened them and took a whiff. Not good.

I also know from personal experience that the new plastic containers, including some with those peel-off seals, have a much shorter shelf life than the traditional metal cans. That same article mentioned food in plastic containers are also "canned goods" so I thought that was relevant.

Even the tin can is changing. For years, the three-piece can (made from a top, a bottom, and a body formed from a plate soldered into a cylinder) was the only can around. Now there are two-piece cans, which eliminate the side seam and one seamed end. These cans are made by feeding metal into a press that forms the can body and one end into a single piece.
Incidentally I just bought a can of salmon made without bottom or side seams. It's stamped to expire in 2015. That's a long time (for me), but I'll still trust it for that time, because I've long been impressed by the quality of cans from this particular manufacturer.

And lastly, from that same article is a list of problems to look for when determining if a container has been compromised...
How to Recognize Can Defects

"Never eat food from a tin can with bulging ends" was a maxim many grew up with. Bulging was one of several clues that might indicate contamination of food packaged in metal cans. Guidelines have been adapted for recognizing defects in cans made of plastic and other materials, as well. The guidelines are:

Metal Cans

* an obvious opening underneath the double seam on the top or bottom of the can
* a can with bulging ends
* a fracture in the double seam
* a pinhole or puncture in the body of the can
* an unwelded portion of the side seam
* a leak from anywhere in the can

Plastic Cans

* any opening or non-bonding in the seal
* a break in the plastic
* a fractured lid
* a swollen package

Paperboard Cans

* a patch in the seal where bonding or adhesive is missing
* a slash or slice in the package
* a leak in a corner of the package
* a swollen package

Glass Jars

* a pop-top that does not pop when opened (indicating loss of the vacuum)
* a damaged seal
* a crack in the glass of the jar

Flexible Pouches

* a break in the adhesive across the width of the seal
* a slash or break in the package
* a leak at a manufactured notch used for easy opening
* a swollen package
I've personally seen many of these. Good stuff to know. I was particularly annoyed to find a swollen flexible pouch of tuna. According to the expiration dates they seem to have a shorter shelf life. So I opted for the tuna in the metal can on my next purchase. Always consider that you don't know how strict was the canning and manufacturing processes. You also don't know how the can was handled on its way to you, whether its viability and/or integrity has been compromised along the way, or how long it's been on its way to you (i.e. in the case of no expiration dates).
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Old 10-20-2009, 12:06 AM
Spoke Spoke is offline
Join Date: Dec 1999
Originally Posted by raindrop View Post
Also, cans are definitely NOT good for indefinite periods, especially those which contain acidic foods, e.g. tomato sauce, fruit juices, etc. Perhaps there's something about being at the bottom of a river that helps maintain the vacuum seal, but I've personally thrown out many old cans that were visibly leaking and bulging, so I can't accept that they are okay for indefinite periods.
I have used home-canned tomatoes that were at least 8 years old for chili. They were delicious! With the home-canned stuff, you just have to be sure the lid hasn't popped. (Which is the point of the dimpled lid.) (A couple of the older jars of tomatoes had lost their seals and were no good.)

Home-canned tomato salsa that was ten years old was as good as new.

I have noticed that older jars of squash and okra lose their color and flavor. That doesn't make them dangerous. Just not tasty.

(How do I know all this? I inherited a lot of stuff from an aunt, including her home-canned vegetables, some of which dated back a decade or more. Didn't see the sense of wasting the veggies, so I ate them!)
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Old 10-20-2009, 07:21 AM
don't ask don't ask is offline
Join Date: May 2001
Location: Sydney, Australia
Posts: 17,602
I have used various old, old cans of stuff so many times, without ill effect, that it wouldn't cross my mind to question how old canned food is. Some of the places I have gone shooting have had cans of stuff so old that none of us recognized the labels. After all you get to check out the contents before you eat them.
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