Glass jars for freezing pellets?

[MaxStout]

The other reason I don’t like plastic alone is that the O2 permeability is not zero. According to the analysis in the FoodSaver Mylar roll Amazon link, the “leading” plastic bags (Which are presumably FoodSaver) range from 34-55 cc/m^2 per day, at one atmosphere and 100% oxygen. For a 10”x12” bag that works out to over 5 cc/day. Of course, air is not 100% O2 and the pressure differential isn’t one atmosphere, but I’m guessing it’s closer to 1 cc/day than not. In any case, I’m confident that you get more much O2 ingress in a plastic bag than in a properly sealed mason jar. There will be a crossover point where the mason jar is better. The only question is how many days it actually is and how frequently do you open the bag/jar?

Maybe somebody on that Amazon "calculation" misplaced a decimal place or two. The sealed bag I have pictured above was last sealed about 3 months ago. At 5cc/day, that thing should look like a pillow.

I have a 1lb pkg of pellet hops I vac sealed in 2020, and it's still stiff as a brick, sitting in my deep freeze.

In contrast, a mason jar evacuated 80% by a Foodsaver will have 20% air, or about 3psi. The partial pressure of the O2 will be ~0.6psi. Put another way, if there's, say 500ml of space inside a typical quart jar full of hops (low packing density), you have the equivalent of 20cc of O2 at 1 atm from the beginning.

The jar method could work if you use a pump that pulls a higher vacuum.

 

[day_trippr]

At 5cc/day, that thing should look like a pillow.

Permeability works both ways. If O2 is crossing barriers in one direction it's also crossing in the other.

Cheers!

 

[kohalajohn]

Hmm. This might satisfy my constraints: FoodSaver® Reusable Gallon Vacuum Zipper Bags https://a.co/d/foRRpHL

Reusable. Put the YVH Mylar bag inside. I will check this out.

That product probably works great, but they won't create the same vacuum as a vacuum machine channel bag does. The bags normally used in. FoodSaver machines and their kind have a back sheet that feels pebbled. They are called channel bags because the pebbled side creates a one way channel for air to be sucked out for that tight crinkled look. With freezing food, you can't just suck out the top as the food might become compressed and block the vacuum, leaving a pocket of air behind it.

Perhaps there is some air ingress into even the vacuum channel freezer bags, and of course after enough time there would be, as it is plastic and not glass or mylar. But in light of the fact that the bags still look tight and crinkled after years in the freezer, suggests that it is a trivial amount for the periods of time we are dealing with.

And while glass and mylar are 100% impermeable, you have to open the top. Its a bank vault with three concrete walls but an open door in the front wall.

If you put a mylar bag, with an open top, inside a plastic vacuum bag for purging, then I think why not just use the plastic bag and drop the mylar. Again, the mylar is a bank vault with three impermeable walls and an open front door in the fourth.

Maybe it doesn't matter. Maybe five years protection is more than is needed.

I surely will be using my hops in a year or two. And all of the above systems seem good enough for that. Nobody is complaining about hop spoilage as an issue. Probably just using a glass jar in a freezer would be good enough. This is not about stopping degradation, it's about slowing down degradation to a period less than our usage time.

Use the method you like. I like the vacuum bag machine. I pack meat and salmon a lot and its invaluable for that. I also vacuum pack meat for sous vide in my Brewzilla gen 4 and it's great for that.

For me, for my wishes, I just received this baby:

https://www.amazon.ca/dp/B0BRJ3X2C1?ref=ppx_yo2ov_dt_b_fed_asin_title&th=1

 

[mac_1103]

Perhaps there is some air ingress into even the vacuum channel freezer bags

The issue raised was oxygen permeability not loss of vacuum. Oxygen molecules can diffuse across the bag (in both directions as already mentioned). Since the vacuum that a food saver pulls is far from complete, there's still some oxygen inside the bag. Those oxygen molecules will do oxidative damage to whatever is inside the bag. And as they are consumed in oxidation reactions, they will be replaced by more oxygen molecules diffusing into the bag, leading to more damage, etc.

This is all theoretical, of course. In practice the storage method seems to be more than adequate to preserve all sorts of things for quite a long time.

 

[mac_1103]

That product probably works great, but they won't create the same vacuum as a vacuum machine channel bag does. The bags normally used in. FoodSaver machines and their kind have a back sheet that feels pebbled.

Hard to say for sure, but the bags pictured at that link appear to have a pebbled surface.