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How do freezing food/expiration dates work? Answered

There's a supermarket right next to my apartment, so I usually go there once a week to buy groceries for the next 7 days or so. I notice that a lot of food has an expiration date that is not far off, so it feels like I have to hurry and eat all of my meat and fruits in vegetables and then if I'm trying to stretch food for another week, all I have left is rice and some odds and ends. I don't know much about freezing/thawing and what you can and can't freeze. My question is, how can I learn about the proper ways to freeze things to extend their usability and not have to buy food again every week. Any pointers


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1 year ago

Freezing slows or stops most baterial growth. It will not kill all baterias, so they just start up again after heting it up again. Think of freezing as "Pause" for the bacterias.
See https://ecampusontario.pressbooks.pub/microbio/ch... for how different groups of bact are affected. Basically, the stuff to worry for our food are Mesophiles, Pyschrotophs and Psychrophiles.
fungis also are slowed but normly not killed my cold. Also there: They will continue after the warming-up.

if you have cells with lots of water in them, the ice cristal which grows inside the cell normally pierce the cellwall.
There are a few foods which have sort of a freece-modifier in them: The ice grows more uniform and less cristal-like.
Thats why a piece of meat will have a lot of juice coming out if you thaw it out as many of the cells are punctured and leak water...
Thats also why freezing kills some % of baterials and fungi: The ice-spikes growing int heir cells puncture and damage cells. If this damage is sufficient, a cell dies. Thats why freezing does nothing against Virus: A virus is no functional cell but DNA-fragment with delivery-methods.

But basically you can freeze almost everything. The less water it has the better / the same it will be if you thaw it out afterwards.
If you freeze stuff like berries, be aware that they will be a little bit smushy after the cold... Perfect for jam and softice-topping and such stuff.

I can only secondf the inputs from Downunder:
- dont refreeze
- freeze with as less air as possible

If you dont have and dont want to buy a vacuum-sealer, there is a quite simple trick:
- Fill a container with water
- Put your stuff in a airtight ziplock suitable for freezing
- insert the bag into the water with its top above the water-line.
- the weight of the water pushes evently onto the bag and forces air out surprisingly well (The deeper you insert the better it works, so deeper bags are of an advantage here)
See Time 00:46 @

refer to the FDA-Chart for times you can store foods:

And yes: Ask the old folks! They often grew up without proper fridge and preserved food themselves with various methods. Heat-sterilisation (Jams and stuff), Drying (Beef jerky for the win!), pickling, ...
... and they survived the trip of preserving food and are here to tell the tale. Thats a "success"-Tag in my book. ;)


1 year ago

Not all things are really suitable for freezing if you want to preserve best quality.
Take soft and loose fruit like blackberries.
Even in a vacuum container they usually come out more like mashed berries.
This is due to the breaking of cell membranes when the water in the berries freeze.
Other things, like cheese and milk simply can't tolerate freezing very well as it changes/seperates their contents.
Milk is a lot of water, some fat and other organics, the fat and water freeze at different temperatures.

In general you can freeze everything you find in the supermarket freezer and then some.
Meat, fish, brad, soup, sauce and so on.
There is two things you should never do though.
Firstly: Never, ever freeze something that was frozen and thawed up.
Just promotes bacteria growth and most will survive freezing...
Secondly: Always try to freeze without air in the packing.
Having air in a bag with meat for example promotes freezer burn and dries the meat out.
Most freezers these days come with a nice chart to tell you how long stuff can be kept frozen without loosing too much quality.
Going a bit over, if properly packed is no big deal but as said, quality suffers first, if you go overboard taste as well.

If you are after saving a buck and some time for shopping then consider buying and cooking in bulk.
Invest in a vaccum sealer - the bags are actually washable and reusable within limits.
Meat you use what you need for the day you bought it, the rest cut into portion sizes, bad and freeze - don't forget to write on the bag what is in it and you put it in the freezer ;)
FIFO is not just a computer terms;)
First IN, First OUT.
For liquid stuff like sauces and soups I found two good working ways to freeze them.
Either in a bag standing up in the freezer until frozen, then vacuum seal.
Or by using a freezer container where you first place a sheet of plastic foil onto the surface - cling wrap, breakkie wrap or whatever that clear sticky foil is called in your area.
It seals the surface, prevents freezer burns and makes a noticable difference in quality when it thaws up again.
Certain foods should not be freezed, like everything that goes bad quickly after cooking.
Pasta and egg dishes are prime candidates to avoid here as it is not worth risking bacteria growth over freezing it.

If you want some really hands on tips and tricks I suggest to have some talks with the old folks around you.
My grandparents used to fill big shelves with jars of things like pickeles, fruits and things I never dared to eat.
But they also kept two freezer filled at all times.
It is one thing to learn to cook for more than just one meal, doing it with the idea of freezing most of it is much easier with real world input and ideas.