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Home Forums General Discussion comercial vacume packers and retort bags

This topic contains 7 replies, has 3 voices, and was last updated by  promethious 3 years, 4 months ago.

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  • #36905

    caverdude
    Participant

    http://www.officialvacupack.com/index.php?cPath=70_75

    Check this out… anyone used these larger vacume packers and these retort bags? the retort bags are like the mre bags from what I understand. so you are actually canning in a bag.

    http://larrydgray.net

    http://larrydgray.wordpress.com

    #41768

    elnav
    Member

    We recently acquired one of the big units in anticipation of going off grid soon.

    Reading the manual I find them warning the vacuum bag process is not a substitute for canning. BUT fter a bit of thinking I realized what the distinction is. Canning puts the food at an elevated temp for a period of time ( at least 30 min) even when using a pressure cookerf.

    This heat step is crucial for pasturizing the food and killling any pathogens. Short duration heat is not sufficient to kill some stubborn bacteria. This is what is behind the food industry regulations forbidding sale and distribution of non pasturized milk.

    After reading the instructions carefully, I have come to the conclusion that vacuum packing is safe if you pasturize and chill the food first. If you vacuum pac hot foods expect weird results due to the temperature changes as the food cools in the bag whether you freeze it or not.

    The manual gives a long list of foods and how long their shelf life is extended. Fresh foods have the shortest storage life. Especially if they are stored at room temp. This is when bacteria trapped in a vacuum is still likely to be active. Some bacteria is anaerobic and will thrive when deprived of oxygen.

    Despite the above comments I think these vacuum bags are great!

    Right now its too early to have results from our own experiments.

    We currently have 24 dozen quart canning jars ready to use and the pinks are beginning to run. We are looking for a large pressure cooker that can handle at least half a dozen quart jars at a time or preferrably a full dozen.

    #41769

    caverdude
    Participant

    Well I assumed after vacume packing that canning procedures would be next. Such as boiling or simmering for a half hour or more. The contents might expand during this but won’t rupture the bags I think. And cooling creates more vacume in the bags as it would in jars. Do you have the retort bags? Have you canned in them? Will you try and tell us how it works out?

    http://larrydgray.net

    http://larrydgray.wordpress.com

    #41772

    elnav
    Member

    Boiling or simmering after vacuum bagging. That I have a bit of a problem with. Pasturizng requires high heat and time duration. The heat sealing bags are thermoplastic not thermoset. The heat and time required for pasturizing wiil cause the bagged food to outgass meaning some expansion and internal pressue will develop inside the vacuum bag. Just how much this might weaken the bag is a variable no one can accurately determine.

    With conventional glass jar canning you can tell if the vacuum seal is intact by the pop and ring of the metal lid. Bagging has no such positive indicator. I used to work in a place wher we used vacuum pumps so I am aware of the limitations of the light duty consumer products we are currently discussing. A buddy has been a supervisor of a canning plant for 20 some years. He told me a bit about the process of food preservation.

    I will be reporting on our experiment as it progresses.

    #41773

    elnav
    Member

    Boiling or simmering after vacuum bagging. That I have a bit of a problem with. Pasturizng requires high heat and time duration. The heat sealing bags are thermoplastic not thermoset. The heat and time required for pasturizing wiil cause the bagged food to outgass meaning some expansion and internal pressue will develop inside the vacuum bag. Just how much this might weaken the bag is a variable no one can accurately determine.

    With conventional glass jar canning you can tell if the vacuum seal is intact by the pop and ring of the metal lid. Bagging has no such positive indicator. I used to work in a place wher we used vacuum pumps so I am aware of the limitations of the light duty consumer products we are currently discussing. A buddy has been a supervisor of a canning plant for 20 some years. He told me a bit about the process of food preservation.

    I will be reporting on our experiment as it progresses.

    #41775

    caverdude
    Participant

    Well, thats how MRE’s are done. They are heated after packaging to kill bacteria. If done in a presure cooker it might not boil at 212 right? so maybe one must use a presure cooker.

    http://larrydgray.wordpress.com

    http://larrydgray.net

    #41776

    elnav
    Member

    I am not familiar with US MRE cooking facilities but from what I remember of the Canadian military these are not packaged exactly the same as the consumer vac bagging units that we are discussing.

    The advertising people have a bad habit of exaggerating their hype to make people think their stuff is more than it really is.

    #49374

    promethious
    Participant

    caverdude.. although this is an old thread, i just came across it today.. even joined so i could reply to this thread… you are correct.. MRE’s (IMP’s in canada) are done in retort bags.. some, usually in the case of military rations, the food is pre-prepared and cooked before packaging.. this isnt “always ” the case, but it is for the most part, and as u stated, reheated viz a heater pack or water and boiled.. usually 5.3mil thickness bags.. they come generally in silver and/or white for commercial usage, olive drab/green exclusively for military usage, and then for general use.. it is in gold..

    the bonus is that you “CAN” cook in these bags.. as opposed to mylar which isnt safe.. the retort bags essentially become the can… or in the case of canning, the mason jar.. just…easier to pack, easier to store, easier to ship… but they have the increased protection because of their (depending on specific model) 3 and 4 layers of materials.. it increases protection from gas’s…oxygen and light (which is the killer for food storage)

    and elnav.. this is the same process used for canadian rations.. the process is the same completly

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