What you said is the best way. I would suggest getting a few gama seal lids. For the buckets you are using out of, it makes getting in and out of easier. If it is truly long term, you will not be getting in and out of all 8000 buckets, just a few. Also it is generally accepted that flour does not last too very long.
I would store these long term with desiccant packs and Oxygen absorbers too. You can find lots of videos on Youtube.
Thank you for the reply. To confirm, any new/clean bucket will work correct?
Yes. Any new standard plastic bucket should work fine. A used,clean "food grade" bucket (one that has never held toxic substances) will also work.
Also, are you saying to put the Mylar bag in the bucket, fill up the Mylar bag, and then close the bucket lid (with the oxygen packets in with the flour/sugar/etc)?
Typically, if you are using a full bucket-sized bag (as opposed to multiple smaller bags), you put in the bag in the bucket, fill with food, add 02 absorbers, seal the bag, possibly add some more 02 absorbers in the bucket outside the bag and close the lid.
I guess I’m not following if the Mylar bag can be re-open/closed repeatedly after first going in.
Once you reopen the mylar bag after storage, the 02 seal is broken. It can be folded over to minimize 02 access or possibly can be resealed, but it is generally time to start eating once you open it. I prefer to use multiple 1 gallon bags in a 5 gallon bucket to keep extra food sealed after opening, but it is up to you.
Does vacuum sealing help in anyway?
It greatly reduces the amount of air in the package and also shrinks it somewhat. Makes it easier to ensure the 02 absorbers can get all the oxygen or can theoretically be done with no 02 absorbers.
Answered inline above.
The bucket and mylar bags fill two complementary, but different needs. Long term storage means protecting food from light, oxygen and pests. The bucket will allow for easier storage and to protect from pests (particularly chewing mice). The mylar bag can be sealed air-tight to prevent oxygen from getting in.
Edit: You are also looking to protect food from water vapor in the air. Again, the bucket may provide a good seal, but the mylar provides and excellent one.
Thank you so much for the help. Very helpful!
Do you have specifics foods that are recommended for storing like this? Or foods that should not be seal in Mylar and O2 absorbers?
Am I reading correctly that an O2 absorber should NOT be used with sugar?
Check your buckets every year or so. Some of my recycled food buckets developed cracks (splits) on the bottom.
I keep sugar in buckets with gamma lids without mylar bags, has not clumped after 4 years.
What do you put your sugar in, if you don’t put in Mylar bags? Just it’s original paper packaging?