Are mason jars air tight?

I've never used jars to brew, but I do use them to can, mix drinks, drink coffee out of, transport and store food.

I would not recommend. Mason jars are made to be hot packed, its a combination of heating the plastic on the lids and the vacuum you produce by filling with hot stuff or processing with boiling water that creates the seal. Having the opposite of a vacuum and no heat seems like a recipe for lid failure, beyond that if the seal did work you could be above the pressure threshold for the glass and explode them.

 

This would be my concern

 

I saw a you tube video and the dude opened a home brew fresh from a canning jar. No fooling. I wanted to know for the novelty of it, and lo it works.

 

I have stored yeast in mason jars and have had lids become bent out & up by the pressure. I'm pretty sure you could get away with it if you primed it lightly but I personally wouldn't risk the exploding jar possibility.

 

You might get a good seal, and, indeed, there's lots of empirical evidence to support that. But keep in mind that the lids were designed to seal under the negative pressure created as the contents cool. It's the vacuum that holds the lid in intimate contact with the jar's rim. The band is there simply to hold the lid in place until that happens (it's generally recommended to remove the band once the lid seals to minimize the dark, damp areas where mold and other uglies might thrive). Also, note that the lids are designed to vent excess pressure (if you've ever done a hot water bath, you've seen bubbles escaping through the lid under the pressure created by the hot contents). That's why you're not supposed to crank the bands down tight.

The bottom line is that it may work. But I wouldn't be surprised if you lost a few beers using this technique.

 

You have any empty soda bottles laying around? I would use these before the mason jars.

 

I've put them in the freezer with liquid before. They broke because the tensile strength is crap. A mess of frozen water and glass to clean up. I wouldn't want to think about how pissed I'd be if I had to clean up bottle bombs.

 

I mean it's possible to can literally anything, however I would not put any beer I deemed of high quality through the process required to create an airtight seal for mason jars. It works great for pickles and things of that nature but boiling potentially live yeasts in beer would be a bad thing, provided that the beer wasn't already pasteurized. If that's the case then can away!

 

How highly have you safely carbonated in mason jars?

 

Wide mouth Mason jars are actually ok to freeze, you just need to leave more headspace to accommodate the expanding frozen whatever. Standard ones will break at the shoulders.

 

I use Mason jars for short term yeast banking. I had the bottom blow out of one because it wasn't quite done fermenting the sugars and I snugged the lid up a bit too much. I would not put anything under pressure in a Mason jar.

 

Ran out of bottles while bottling today, so I put the last bit into a mason jar. I will report back if and only if it explodes.

 

I have stored homemade wine in Mason Jars but never beer. For about the first month I "burped" the jar to let off some pressure from left over active yeast. I've had some wine in those jars for about a year now; so far so good. I don't think I would try with beer though. I care more about my home-brewed beer than my wine.

 

I use mason jars for yeast storage, but it is always aggressively refrigerated and the lids are on loose over sanitized saran wrap. If I was desperate enough to bottle in mason jars, I'd wrap the glass in duct tape and store in a cooler or other container to minimize possible bottle bomb damage. There is potential for future injury if the first batch of mason jar beer doesn't explode and you try it again. Sooner or later...Boom. Old soda bottles are fine if you'll be drinking the beer within a couple months and I endorse them as the safe, sensible choice.

I also encourage you to improve relations with your in-laws...

 

So it didn't explode, but it also didn't carbonate. And it fell over and leaked, so not completely air tight.

 

As I said above, some people report success 'bottling' in Mason jars. While I won't say that they're making it up, the design of the lid suggests that your experience is the more likely result. You can drive a screw with a hammer, but that's a p*ss poor substitute for duct tape... er... I mean a proper screwdriver