Common misconceptions about Vacu-vin (Don't use one for beer!)

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domtronzero

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I posted this on BA some time ago.

I don't think anybody ever put much thought into this, but I was hoping to help clear the air for future beer drinkers (only those that'll actually read this though, I guess).

Prerequisite knowledge:
CO2 in solution is a function of the partial pressure of CO2 above the solution - Henry's Law - not a function of the partial pressure of any other gas above it. Earth's atmosphere is only a tiny fraction of CO2 (0.039%) and therefore, the partial pressure of CO2 in air in the bottle is negligibly reduced when using a vacuum sealer. Therefore, it doesn't actually "pull" any CO2 out of suspension. It does, however, remove a good portion of oxygen out of the headspace, reducing the amount of oxidation that happens in the bottle.

The real issue is this:
The vacuum sealers are a one-way check valve. They allow a pressure to be reduced on one side of the apparatus (within the bottle). However, with carbonated beverages, once the CO2 starts coming out of suspension to fill the headspace, the pressure inside the bottle increases to a level slightly over atmospheric conditions, the check-valve allows that pressure to be purged through the valve, and out of the bottle. I made this dandy little pic using AutoCAD to explain (you'll probably have to open it in a new tab to read the small text below the bottles):

scaled.php


A simple stopper keeps the pressure inside and does not allow the beer to become flat just like a vacuum stopper, but since there is no check valve, the simple stopper will keep the carbonation in suspension until there is enough pressure to blow the stopper out of the neck (which has happened to me a few times). The vacuum sealer will simply open and purge the excess pressure, and reduce the amount of CO2 in suspension in your beer.

tl;dr: vacuum stoppers bad, simple wine stoppers good.

In summation:
1. A vacuum sealer WILL NOT pull a noticeable amount of CO2 out of solution (by means of Henry's Law).
2. A vacuum sealer will still make your beer go flat due to the check-valve mechanical nature.
___________________________________
Another point of interest:

Q: What is the pressure that the check-valve opens at?
A: I don't know exactly, but it really isn't too much. I've played with one and have blown air through it (holding it up to my mouth) and it wasn't difficult to get it to open up. Human lungs can really only exert about 2 psi of pressure (this was an experiment we did a long time ago in college where we blew into a U-tube filled with water and measured the height difference).

With the average beer containing 2-3 volumes of CO2 dissolved in solution, there could be a pressure of at least 1 atmosphere above atmospheric. At serving temperature (38F) I have to keep my kegs at about 12-17 psi to achieve 2.5-3 volumes of CO2 in solution, with 30 psi required to maintain 4.5 volumes for my sours. This is a substantially large amount of pressure exerted in bottles. This is why most sours and Belgian beers are bottled in thick champagne-style bottles that can withstand that amount of pressure.

Therefore, the pressure in your average bottle of beer is much more than enough to open the check-valve on the vacu-vin.
 
This seems like a retarded amount of info/technical data for something that is painfully obvious...
Sorry, you don't have to read it (and I'm assuming you didn't). It's not painfully obvious. Go look on the other sites about how many people rave about Vacu-vin stopper systems. Seriously. People think they're the **** and they're not.
 
Sorry, you don't have to read it (and I'm assuming you didn't). It's not painfully obvious. Go look on the other sites about how many people rave about Vacu-vin stopper systems. Seriously. People think they're the **** and they're not.

I glanced it over, posted my comment and then read it in it's entirety.
I am still facepalming that people think this is a wise investment for beer.

tl;dr - we the people of BT are not the "tools" on the other sites
GOD damnit we are the elite.

'murica
 
The real question is, why on earth would anyone legitimately need to re-seal a beer?
For the most part I bottleshare with one other guy. That's it. A 2-man tasting team. We like to open a ton of bottles and put down a bunch of different beers in a single sitting (we also like blending beers and other **** I'm sure you'll all chastise me for). When we open bottles we typically drink about half of them in one sitting, then revisit them later on in the evening if we're getting drunk and don't want to continue opening bottles.

Oftentimes, my girlfriend works late and can't make it to the shares before all the beer is gone. I will reseal bottles of "special" stuff and put them in the fridge for her to drink when she gets home from work. She appreciates it, and it makes me feel good about myself.

But who am I kidding. Queue the mouth breathers and their battle hymn, "DRINK THE WHOLE DAMN BOTTLE IN ONE SITTING, PANSY!!!"
 
The real question is, why on earth would anyone legitimately need to re-seal a beer?

Real talk

I sometimes like to solo 4 or more bombers on any given week night. Sometimes I like to dabble across the board and drink a glass of one, then another before returning back to #1. Its my way of tricking my palate into thinking im drinking something different even though I drank it 3 glasses ago. I just put the original cap back on the bottle and in the event I backfat the bottle is ready to go when I wake up.
 
For the most part I bottleshare with one other guy. That's it. A 2-man tasting team. We like to open a ton of bottles and put down a bunch of different beers in a single sitting (we also like blending beers and other **** I'm sure you'll all chastise me for). When we open bottles we typically drink about half of them in one sitting, then revisit them later on in the evening if we're getting drunk and don't want to continue opening bottles.

Oftentimes, my girlfriend works late and can't make it to the shares before all the beer is gone. I will reseal bottles of "special" stuff and put them in the fridge for her to drink when she gets home from work. She appreciates it, and it makes me feel good about myself.

But who am I kidding. Queue the mouth breathers and their battle hymn, "DRINK THE WHOLE DAMN BOTTLE IN ONE SITTING, PANSY!!!"
If you use a large opening bottle opener and don't destroy the cap, you can reuse the original cap and the beer will be fine for 6-8 hours.

edit: I use this one all the time and the cap stays perfectly in shape.
1.0x0.jpg
 
If you use a large opening bottle opener and don't destroy the cap, you can reuse the original cap and the beer will be fine for 6-8 hours.
Yah I know. But I have these super cheap plastic wine stoppers that are used for the homebrew competition that I run and it's convenient.

I didn't want this to turn into a thread where everyone bashes each other because they choose to drink beer differently than others. I'm an engineer and I like scientific stuff. I had fun "researching" this topic and learned some great stuff in the process. I wanted to share it with other science-minded people (they're is a surprisingly large population of them that are involved here and involved with beer in general).
 
Yah I know. But I have these super cheap plastic wine stoppers that are used for the homebrew competition that I run and it's convenient.

I didn't want this to turn into a thread where everyone bashes each other because they choose to drink beer differently than others. I'm an engineer and I like scientific stuff. I had fun "researching" this topic and learned some great stuff in the process. I wanted to share it with other science-minded people (they're is a surprisingly large population of them that are involved here and involved with beer in general).
All good. Engineers gonna engineer.
 
Now you are obligated to verify your claims with controlled experiments and quantify how much CO2 is actually lost over time.
 
Can't drink the whole beer? Drain pour that chit, ya cheapskate!

I prefer this to "drink it, ya pansy" because cheapskate is less derogatory than pansy and I don't like to encourage overconsumption.
 
I continue to wonder if a CO2-additive cap will ever be created for beer. I can hope...
I don't think this would be very hard to do, it's pretty easy to drill a hole in something and shove a Schrader valve in. Finding the appropriate thing would be the biggest challenge, by far. But once you have it, adding a valve should be fairly simple.
 
I continue to wonder if a CO2-additive cap will ever be created for beer. I can hope...

The second someone accidentally overpressurizes a glass bottle and it blows up in their face, that company will be out of business and the owner swinging from the rafters.
 
I've used Vacu Vin on beers for short periods of time with minimal pumping with good results. The way I figured, I was trading carbonation for oxidation - which I was ok with. Maybe that was a bad assumption.

What if you were to plug the holes at the top of the Vacu-Vin after creating the vacuum? Would that fix the issue?
 
The second someone accidentally overpressurizes a glass bottle and it blows up in their face, that company will be out of business and the owner swinging from the rafters.

It shouldn't be too hard to build in a number of simple safety features to prevent that.

First, you'll have some sort of pressure valve between the CO2 storage and the bottle, which can be set to a maximum value a little below what most beer bottles are rated at.
Second, have whatever method you have for keeping the cap on the bottle break its own seal with the bottle's mouth when that same pressure is reached, preventing overpressure in the event of a valve failure.
Last, you can add in a separate relief valve with a blowoff disk to the cap rated just a little higher pressure than the design pressure of the main valve and the cap. That way even if the main valve fails, and the cap has been wedged in weird, or taped on or whatever, the blowoff valve will still break open before the bottle does.
I've also never seen a bottle failure be catastrophic. I know it can happen, but all the failures I've seen appear pretty anticlimactic. I suspect that, combined with a few safety features, could make such a device pretty safe in practice.
 
While I've enjoyed the threadcromancing and post-mortem likes, I must say that this is still an issue that a lot of laymans still don't get.

I'm glad that this has been a valuable resource to many of you, cuz science and stuff.

quinnsi I'll get back to your question in the morning. I'm kinda drunk off mead and autocorrect is getting the best of me right now.
 
The second someone accidentally overpressurizes a glass bottle and it blows up in their face, that company will be out of business and the owner swinging from the rafters.
I've got a homebrew story about this. Thankfully it didn't end in casualties. Seriously.
 
I've used Vacu Vin on beers for short periods of time with minimal pumping with good results. The way I figured, I was trading carbonation for oxidation - which I was ok with. Maybe that was a bad assumption.

What if you were to plug the holes at the top of the Vacu-Vin after creating the vacuum? Would that fix the issue?
Short answer: yes.

Long answer: depends on what you use/how you plug the holes.

I would imagine that if you used some sort of rubber stopper inserted into the hole that it would work fairly decently. What are you thinking of using?
 
Link please.
When I was a beginner brewer I thought it would be a good idea to save some wort from a brew in capped 22 oz bottles to use later as starter wort.

I didn't have the cognitive capacity to understand that it needed to be boiled first.

After about 3 days, the bacteria (lactobacillus) had fermented enough, and enough pressure was built up, that 2 of the 4 bottles exploded. They were sitting on a shelf in the hallway near the bathroom. When I got home from work I noticed that my house smelled like vomit and as I was looking around I noticed a 2" shard of glass sticking out of the drywall. And rotten beer everywhere. The walls, the carpet, and the ceiling.

There were tiny shards of glass all over the place, and several pieces of glass sticking out of the drywall. And this was right near the area that my dog slept during the day.

Thankfully nobody was hurt (including the dog), and I put on an apron, a jacket, safety glasses, and gloves to pick up the unexploded bottles. I put them into a plastic tub with a lid and took the entire thing out to the garbage.

It took a week for that area of my house to air-out and for the stink to go away.
 
When I was a beginner brewer I thought it would be a good idea to save some wort from a brew in capped 22 oz bottles to use later as starter wort.

I didn't have the cognitive capacity to understand that it needed to be boiled first.

After about 3 days, the bacteria (lactobacillus) had fermented enough, and enough pressure was built up, that 2 of the 4 bottles exploded. They were sitting on a shelf in the hallway near the bathroom. When I got home from work I noticed that my house smelled like vomit and as I was looking around I noticed a 2" shard of glass sticking out of the drywall. And rotten beer everywhere. The walls, the carpet, and the ceiling.

There were tiny shards of glass all over the place, and several pieces of glass sticking out of the drywall. And this was right near the area that my dog slept during the day.

Thankfully nobody was hurt (including the dog), and I put on an apron, a jacket, safety glasses, and gloves to pick up the unexploded bottles. I put them into a plastic tub with a lid and took the entire thing out to the garbage.

It took a week for that area of my house to air-out and for the stink to go away.
Can you put that in a handy link for me please?
 
Short answer: yes.

Long answer: depends on what you use/how you plug the holes.

I would imagine that if you used some sort of rubber stopper inserted into the hole that it would work fairly decently. What are you thinking of using?

I used tooth picks and it seemed to work OK.
 
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