From watching ‘Inside The Factory’ on BBC they pressure-cook the can with its contents sealed inside, effectively sterilising the food. I presume that’s a difficult thing to do domestically.
You have to pressure can to get rid of spore forming bacteria like B. cereus and C. botulinum. By increasing the pressure you can get to higher temperatures than 100C/212F for long enough to sufficiently kill off the spores. You probably could do this at home if you had the right equipment and know what you’re doing, people pressure can at home all the time. You just have to ensure the contents are hot enough for long enough to be shelf stable.
For pastas and rices (high-starch items in general), it’s not as much a “safety” issue, it’s more of a structural integrity issue. With most home canners and the like, you’d have to pressure cook the grains for a lot longer than their appropriate cook time. It all turns to mush.
On an industrial level they can (presumably) seal and cook the insides much faster. This is why SpaghettiO’s on the stove taste better than microwaved in my opinion.
You can pretty much can anything but somethings are.more difficult than others. Grains may require pressure canning which most.canners don’t bother with.
The main concern with canning is the acidity. Acid mitigates/prevents bacteria growth (particularly botulism which is a risk because it can survive relatively high temperatures). If you are canning grain by itself there is no acid to inhibit the bacteria.
SpaghettiO’s come in a tomato sauce which is highly acidic. And in general a prepared food item can be acid and/or salt adjusted or otherwise include preservatives to protect the food.
“Canned at home” usually refers to a water bath canner. In one of those, the contents of the can do not get above 212F/100C. That is not hot enough to kill the spores of certain nasty bacteria. If the food is acidic, those bacteria can’t grow well, and the canning “works” fine.
Industrial operations are not restricted to a water bath canner. They use a pressure canner, which is like a tougher pressure cooker. The sealed vessel increases the air pressure in the canner, which increases the boiling point of water in the pressure canner. So the contents of the can gets to more like 250F/130C, which is hot enough to kill the spores.
It is possible to get a home pressure-canner. But it’s much more expensive and harder to use than a “normal” canner.
Hi I’m a food scientist. Commercial canned foods are retorted, which is like pasteurization for canned foods. The sealed cans are exposed to high pressure and high heat to kill spoilage organisms and pathogens. These machines are big and expensive so they are only used at commerical scale. In a personal kitchen, it’s often not possible to control the temperature and pressure of canned foods enough to ensure pathogens are killed.
The chemistry of the food also affects how safe it is to can. Pasta is high in water, not very acidic and too low in sugar/salt to stay preserved for long without further processing.
It is often illegal to sell homemade canned goods without special permits, but there are usually exceptions for things like pickles (high acid content acts as a natural preservative) and jam (high sugar content acts as a natural preservative).
I’m confused at this thread as home pressure canning has been a thing for a very long time.
My parents pressure can stuff every season. Mostly green beans, but still. Same pressure canner setups for that would work for pasta wouldn’t it? The difference would just be how long you leave it under pressure I think….?
Spaghetti-O’s have tomato sauce, which is acidic. If the pH is below 4.6, it’s easier to can something safely. You can do it with a water bath canner. If the pH is not below 4.6, you need a pressure canner that can reach 15 psi.
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The sealed cans are subjected to very high temperatures to insure any bacteria is killed.
From watching ‘Inside The Factory’ on BBC they pressure-cook the can with its contents sealed inside, effectively sterilising the food. I presume that’s a difficult thing to do domestically.
You have to pressure can to get rid of spore forming bacteria like B. cereus and C. botulinum. By increasing the pressure you can get to higher temperatures than 100C/212F for long enough to sufficiently kill off the spores. You probably could do this at home if you had the right equipment and know what you’re doing, people pressure can at home all the time. You just have to ensure the contents are hot enough for long enough to be shelf stable.
For pastas and rices (high-starch items in general), it’s not as much a “safety” issue, it’s more of a structural integrity issue. With most home canners and the like, you’d have to pressure cook the grains for a lot longer than their appropriate cook time. It all turns to mush.
On an industrial level they can (presumably) seal and cook the insides much faster. This is why SpaghettiO’s on the stove taste better than microwaved in my opinion.
You can pretty much can anything but somethings are.more difficult than others. Grains may require pressure canning which most.canners don’t bother with.
The main concern with canning is the acidity. Acid mitigates/prevents bacteria growth (particularly botulism which is a risk because it can survive relatively high temperatures). If you are canning grain by itself there is no acid to inhibit the bacteria.
SpaghettiO’s come in a tomato sauce which is highly acidic. And in general a prepared food item can be acid and/or salt adjusted or otherwise include preservatives to protect the food.
They have hugely expensive food processing equipment to do it safely.
“Canned at home” usually refers to a water bath canner. In one of those, the contents of the can do not get above 212F/100C. That is not hot enough to kill the spores of certain nasty bacteria. If the food is acidic, those bacteria can’t grow well, and the canning “works” fine.
Industrial operations are not restricted to a water bath canner. They use a pressure canner, which is like a tougher pressure cooker. The sealed vessel increases the air pressure in the canner, which increases the boiling point of water in the pressure canner. So the contents of the can gets to more like 250F/130C, which is hot enough to kill the spores.
It is possible to get a home pressure-canner. But it’s much more expensive and harder to use than a “normal” canner.
Hi I’m a food scientist. Commercial canned foods are retorted, which is like pasteurization for canned foods. The sealed cans are exposed to high pressure and high heat to kill spoilage organisms and pathogens. These machines are big and expensive so they are only used at commerical scale. In a personal kitchen, it’s often not possible to control the temperature and pressure of canned foods enough to ensure pathogens are killed.
The chemistry of the food also affects how safe it is to can. Pasta is high in water, not very acidic and too low in sugar/salt to stay preserved for long without further processing.
It is often illegal to sell homemade canned goods without special permits, but there are usually exceptions for things like pickles (high acid content acts as a natural preservative) and jam (high sugar content acts as a natural preservative).
Edited for grammar
I’m confused at this thread as home pressure canning has been a thing for a very long time.
My parents pressure can stuff every season. Mostly green beans, but still. Same pressure canner setups for that would work for pasta wouldn’t it? The difference would just be how long you leave it under pressure I think….?
Spaghetti-O’s have tomato sauce, which is acidic. If the pH is below 4.6, it’s easier to can something safely. You can do it with a water bath canner. If the pH is not below 4.6, you need a pressure canner that can reach 15 psi.
Why are people home-canning stuff? It’s objectively the worst kind of food even when commercially done.
(Apart from Heinz baked beans)