Naked Science Forum
General Science => General Science => Topic started by: Pseudoscience-is-malarkey on 26/02/2022 20:16:35
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Is it better to air seal our food or simply put it in the freezer?
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Is it better to air seal our food or simply put it in the freezer?
Both
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If food is not sealed in a freezer it will normally freeze-dry over time due to water having a vapour pressure at negative temperatures meaning ice in the food can sublime and recondense on the coils. But you can usually freeze it for a few weeks open.
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In order to preserve food, we have invented all kinds of storage methods and technologies. Most of us use fresh storage like the refrigerator and freezer while some use the canning technique. But has anyone of you ever thought of using air sealing machines that have been invented? Air sealing machines are special machines that seal off food by extracting air and sealing it in a can or a jar. This method is supposedly modern and much more efficient than the traditional freezing and canning methods, because supposedly it uses less food and there is less wastage. What do you guys think of this new technology? Is it worth trying?
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If food is not sealed in a freezer it will normally freeze-dry over time
Warburtons still used to pack their bread in waxed paper long after everyone else was using polythene. I once bought a loaf from a garage that was storing them in the freezer, and by the time it had thawed out it was still as solid as it had been when frozen.
You get much the same result if you put thawed and frozen bread together in the same bag before the frozen has thawed.
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But has anyone of you ever thought of using air sealing machines that have been invented? Air sealing machines are special machines that seal off food by extracting air and sealing it in a can or a jar. This method is supposedly modern and much more efficient than the traditional freezing and canning methods, because supposedly it uses less food and there is less wastage. What do you guys think of this new technology? Is it worth trying?
Yes, we use it regularly to extend the keeping of meat when we are away from freezer for a while.
The technique isn’t more modern than freezing and has a disadvantage over canning as the food is not sterilised and any bacteria is sealed in with the meat, including some dangerous anaerobic bacteria.
If we want to store food for more than a few days we would use canned, freeze or dehydrate.
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It's worth remembering that clostridium botulinum- the organism that causes botulism is an obligate anaerobe.
That means it can not grow if there is air present.
Removing air is not a preservative.
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It's worth remembering that clostridium botulinum- the organism that causes botulism is an obligate anaerobe.
That means it can not grow if there is air present.
Oh. Really. I used to believe that vacuum sealing was a good way to preserve food. But why do they continue to use vacuum bags? How does it affect food?
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Vacuum sealing, and heat sterilisation, is very effective to prevent bacterial growth, and if you do not want to go to the heat sterilise method, then you can still vacuum seal and freeze, which will keep the food from bacterial contamination for many months, though the lower the temperature the better, which is why long term frozen storage is at -80C, as pretty much nothing grows at that temperature bacteria and mould wise. If you want even longer storage time then you go to liquid nitrogen temperatures, which is effectively going to last decades, though if you want the longest period you have to put it into a rocket and launch out on solar escape velocity, or at least enough velocity to get out to around the Oort cloud, where the temperature is only around 4K, and it will be there till the sun runs out of Helium and goes into it's red giant phase, when it might get up to 6K for a few million years.