# What's the Straight Dope on beer smoke? **URL:** \ **Category:** Factual Questions\ **Created:** [May 8, 2015, 6:23am UTC](https://boards.straightdope.com/t/whats-the-straight-dope-on-beer-smoke/719535 "2015-05-08T06:23:17Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![pkbites](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pkbites/32/204_2.png) [@pkbites](https://boards.straightdope.com/u/pkbites)\ **Post date:** [May 8, 2015, 6:23am UTC](https://boards.straightdope.com/t/whats-the-straight-dope-on-beer-smoke/719535/1 "2015-05-08T06:23:17Z")
When you open a bottle of beer sometimes what appears to be “smoke” comes out the bottle lip. I’ve tried quite a few [beers](http://www.ratebeer.com/user/4000/ratings/) and always figured it was just water vapor and it had to do with the temperature of the beer and not the beer itself. Honestly, I never really thought about it at all, really. And the wee bit I did think about it I never thought it was anything important or that it had anything to do with the beer itself. But if you’ve ever watched any of the Louisiana Beer [Reviews](https://www.youtube.com/user/ronaldtheriot) you’ll see that many times Ron Theriot points out how much a beer is smoking after being opened. Why? 😕 Is there something I’ve missed. is there actually something important about this? Or is Ron just full of it? Ron seems like a rather pleasant guy, someone I’d like to hang out with. But I don’t know why he rates beer. He likes freaking everything almost. Why rate when you like it all? Rarely does he give a brew a bad rating. So for now I’m thinking it’s he that’s blowing smoke. Or is he? Fight my ignorance. ---
**Author:** ![Saturn\_Dreams](https://avatars.discourse-cdn.com/v4/letter/s/dc4da7/32.png) [@Saturn\_Dreams](https://boards.straightdope.com/u/Saturn_Dreams)\ **Post date:** [May 8, 2015, 7:47am UTC](https://boards.straightdope.com/t/whats-the-straight-dope-on-beer-smoke/719535/2 "2015-05-08T07:47:33Z")
The “smoke” coming out of beer is nothing but air condensing into visible water vapour when the cold air in the bottle is pushed out by the pressurized CO2. This effect has nothing to do with how good or bad a beer is and can be seen with soda or any other cold beverage under pressure. Why does he mention the smoke? You’ll have to ask him. ---
**Author:** ![August\_West](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/august_west/32/18069_2.png) [@August\_West](https://boards.straightdope.com/u/August_West)\ **Post date:** [May 8, 2015, 4:07pm UTC](https://boards.straightdope.com/t/whats-the-straight-dope-on-beer-smoke/719535/3 "2015-05-08T16:07:14Z")
I’ve never watched Ron Theriot (and don’t plan to after reading that he apparently includes "bottle smoke’ in his reviews) but **Saturn Dreams’** explanation is correct. As someone who has been a professional taster of beer, and judged in numerous local, state, and national beer competitions, I will add that if his bottles are producing a large amount of water vapor upon opening, he is probably drinking the beer at too cold a temperature to make a meaningful judgement of it. ---
**Author:** ![bizzwire](https://avatars.discourse-cdn.com/v4/letter/b/958977/32.png) [@bizzwire](https://boards.straightdope.com/u/bizzwire)\ **Post date:** [May 8, 2015, 4:34pm UTC](https://boards.straightdope.com/t/whats-the-straight-dope-on-beer-smoke/719535/4 "2015-05-08T16:34:54Z")
As expressed earlier, this is the adiabatic expansion of the CO2 in the headspace. As it expands upon popping the cap, it cools, resulting in the condensation of water vapor into small, “smoke-like” droplets. ---
**Author:** ![doorhinge](https://avatars.discourse-cdn.com/v4/letter/d/a5b964/32.png) [@doorhinge](https://boards.straightdope.com/u/doorhinge)\ **Post date:** [May 8, 2015, 5:07pm UTC](https://boards.straightdope.com/t/whats-the-straight-dope-on-beer-smoke/719535/5 "2015-05-08T17:07:04Z")
> [@pkbites](#): > > …Ron seems like a rather pleasant guy, someone I’d like to hang out with. But I don’t know why he rates beer. He likes freaking everything almost. Why rate when you like it all? Rarely does he give a brew a bad rating. So for now I’m thinking it’s he that’s blowing smoke. (post shortened, underline added) Follow the money. As a television personality (not a professional taster of beer like **August West** ), if Ron only professes to like two, or three, beers, he’d be limiting the possibility of future show, and personal appearances, sponsorship. If he likes something about most beers, the beer’s marketing team will more likely hire or promote him. ---
**Author:** ![pkbites](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pkbites/32/204_2.png) [@pkbites](https://boards.straightdope.com/u/pkbites)\ **Post date:** [May 8, 2015, 5:33pm UTC](https://boards.straightdope.com/t/whats-the-straight-dope-on-beer-smoke/719535/6 "2015-05-08T17:33:50Z")
> [@doorhinge](#): > > (post shortened, underline added) > > Follow the money. As a television personality (not a professional taster of beer like **August West** ), if Ron only professes to like two, or three, beers, he’d be limiting the possibility of future show, and personal appearances, sponsorship. If he likes something about most beers, the beer’s marketing team will more likely hire or promote him. 😕 He’s just a guy with a camera and a backyard, I think. But he does do a lot of ratings.