# Beer: Is Guiness by the keg nitrogenated? **URL:** \ **Category:** Factual Questions\ **Created:** [September 19, 2001, 5:29pm UTC](https://boards.straightdope.com/t/beer-is-guiness-by-the-keg-nitrogenated/82629 "2001-09-19T17:29:53Z")\ **Posts on this page:** 16\ **Page:** 1
**Author:** ![CaelNCSU](https://avatars.discourse-cdn.com/v4/letter/c/c89c15/32.png) [@CaelNCSU](https://boards.straightdope.com/u/CaelNCSU)\ **Post date:** [September 19, 2001, 5:29pm UTC](https://boards.straightdope.com/t/beer-is-guiness-by-the-keg-nitrogenated/82629/1 "2001-09-19T17:29:53Z")
Just curious. I know that is how they retain the frothiness in the can and now bottle. ---
**Author:** ![Ferrous](https://avatars.discourse-cdn.com/v4/letter/f/8e7dd6/32.png) [@Ferrous](https://boards.straightdope.com/u/Ferrous)\ **Post date:** [September 19, 2001, 5:44pm UTC](https://boards.straightdope.com/t/beer-is-guiness-by-the-keg-nitrogenated/82629/2 "2001-09-19T17:44:17Z")
Yes, it is. The first time I had Guinness on tap, I thought “WTF? Did this keg go stale or something?” Personal preference, I know. There are other “nitrogenated” stouts out now in various microbrew pubs. I personally don’t care for them. I dislike the texture, and feel it detracts from the flavor. I only drink Guinness in the bottled, carbonated form.(Guinness Extra Stout–Export) Just MHO. ---
**Author:** ![CaelNCSU](https://avatars.discourse-cdn.com/v4/letter/c/c89c15/32.png) [@CaelNCSU](https://boards.straightdope.com/u/CaelNCSU)\ **Post date:** [September 19, 2001, 6:07pm UTC](https://boards.straightdope.com/t/beer-is-guiness-by-the-keg-nitrogenated/82629/3 "2001-09-19T18:07:53Z")
I know one other person that prefers it bottled. I love the creamy texture… ---
**Author:** ![Omniscient](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/omniscient/32/3290_2.png) [@Omniscient](https://boards.straightdope.com/u/Omniscient)\ **Post date:** [September 19, 2001, 8:29pm UTC](https://boards.straightdope.com/t/beer-is-guiness-by-the-keg-nitrogenated/82629/4 "2001-09-19T20:29:52Z")
Just keep in mind that the nitrogen isn’t added to the keg, its added to the beer as it flows from the tap at the bar. Similar to the widgets in the bottles and cans which aerate the beer when it is poured. Frankly, I can’t imagine how anyone would prefer the original carbonated bottle brews…eww. ---
**Author:** ![CaelNCSU](https://avatars.discourse-cdn.com/v4/letter/c/c89c15/32.png) [@CaelNCSU](https://boards.straightdope.com/u/CaelNCSU)\ **Post date:** [September 19, 2001, 9:08pm UTC](https://boards.straightdope.com/t/beer-is-guiness-by-the-keg-nitrogenated/82629/5 "2001-09-19T21:08:27Z")
When the brew ferments in bottle that is how it is carbonated. How do they stop that from happening when the keg is priming? Another beer question: What specifically happens when beer sours? ---
**Author:** ![Ferrous](https://avatars.discourse-cdn.com/v4/letter/f/8e7dd6/32.png) [@Ferrous](https://boards.straightdope.com/u/Ferrous)\ **Post date:** [September 19, 2001, 10:16pm UTC](https://boards.straightdope.com/t/beer-is-guiness-by-the-keg-nitrogenated/82629/6 "2001-09-19T22:16:53Z")
**CaelINCSU** , That is not the only method of carbonation, just the one us “beer snobs” prefer, and consider more natural. It’s called “bottle conditioning”. It happens in beer that is not filtered prior to bottling (so that it still contains yeast). A small amount of fermentable sugar (primer) is added during bottling, and the beer is carbonated in the bottle by the action of the yeast (converts sugar to alcohol and carbon dioxide). Most large breweries filter and/or pasteurize (_shudder_) their beer and then use artificial methods to add carbonation. (Not sure of the details). So to answer your 1st question: beer will not carbonate in the keg if no yeast is present, or if all the fermentable sugar has already been consumed. As to your second question, IANAMicrobiologist, but it involves bacterial infection producing yucky things like lactic acid. ---
**Author:** ![barbitu8](https://avatars.discourse-cdn.com/v4/letter/b/839c29/32.png) [@barbitu8](https://boards.straightdope.com/u/barbitu8)\ **Post date:** [September 19, 2001, 10:21pm UTC](https://boards.straightdope.com/t/beer-is-guiness-by-the-keg-nitrogenated/82629/7 "2001-09-19T22:21:43Z")
The best beer mortals can drink is Guinness on tap. Far better than any of the bottled Guinness. How anyone would prefer the bottled is beyond me. BTW, I thought all bottled beer in the USA has to be pasteurized. ---
**Author:** ![CaelNCSU](https://avatars.discourse-cdn.com/v4/letter/c/c89c15/32.png) [@CaelNCSU](https://boards.straightdope.com/u/CaelNCSU)\ **Post date:** [September 19, 2001, 10:25pm UTC](https://boards.straightdope.com/t/beer-is-guiness-by-the-keg-nitrogenated/82629/8 "2001-09-19T22:25:18Z")
Do large microbrews do that? How then do they carbonate it? ---
**Author:** ![Moe](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/moe/32/2972_2.png) [@Moe](https://boards.straightdope.com/u/Moe)\ **Post date:** [September 19, 2001, 10:31pm UTC](https://boards.straightdope.com/t/beer-is-guiness-by-the-keg-nitrogenated/82629/9 "2001-09-19T22:31:11Z")
> [@](#): > > \*Originally posted by Tapswiller \* > \*\*Yes, it is. > > The first time I had Guinness on tap, I thought “WTF? Did this keg go stale or something?” > Personal preference, I know. There are other “nitrogenated” stouts out now in various microbrew pubs. I personally don’t care for them. I dislike the texture, and feel it detracts from the flavor. > I only drink Guinness in the bottled, carbonated form.(Guinness Extra Stout–Export) > Just MHO. \*\* Everyone is, of course, entitled to his or her own opinion but may I just say :eek: 🙂 ---
**Author:** ![Ferrous](https://avatars.discourse-cdn.com/v4/letter/f/8e7dd6/32.png) [@Ferrous](https://boards.straightdope.com/u/Ferrous)\ **Post date:** [September 19, 2001, 11:10pm UTC](https://boards.straightdope.com/t/beer-is-guiness-by-the-keg-nitrogenated/82629/10 "2001-09-19T23:10:29Z")
**barbitu8** No, pasteurization (heat treatment) is neither required nor necessary. As you know, milk and other such products are pasteurized to kill off any dangerous microorganisms. In beer, the alcohol does that job. Many large breweries (Coors being a notable exception) pasteurize anyway because it simplifies the removal of yeast and increases shelf life. If you don’t pasteurize, the filtering process is more complicated (therefore expensive). But most beer connoisseurs (in which category I would count my humble self, even if I don’t like nitro brews) hold that it detracts from the character of the brew. Why is it so important to remove the yeast? Well, bottle-conditioning leaves a fine layer of yeast at the bottom of the bottle, which some find disconcerting. Even though it’s harmless, healthy, and (to some) tasty. BTW, the best beer mortals can drink is Sierra Nevada Celebration Ale. **CaeINCSU** , Most microbreweries I know of use bottle conditioning. Those that don’t just pump in the CO2 like the big boys. **Moe** , Here’s to ya, mate! ---
**Author:** ![escapol](https://avatars.discourse-cdn.com/v4/letter/e/90ced4/32.png) [@escapol](https://boards.straightdope.com/u/escapol)\ **Post date:** [September 20, 2001, 1:46am UTC](https://boards.straightdope.com/t/beer-is-guiness-by-the-keg-nitrogenated/82629/11 "2001-09-20T01:46:52Z")
So what is the ‘real’ Guiness? The stuff they serve in pubs in Ireland is different than that served anywhere else (even the UK…well, I’m not sure about Northern Ireland). Or maybe it’s just the atmosphere in an Irish pub that makes it taste better. ---
**Author:** ![CnoteChris](https://avatars.discourse-cdn.com/v4/letter/c/278dde/32.png) [@CnoteChris](https://boards.straightdope.com/u/CnoteChris)\ **Post date:** [September 20, 2001, 2:24am UTC](https://boards.straightdope.com/t/beer-is-guiness-by-the-keg-nitrogenated/82629/12 "2001-09-20T02:24:01Z")
Shoot, most of this has already been answered. But… **Omniscent** is partly correct. In the format I used, we had a special guy come in and set up the Guinness system. He was certified in some oddball thing and somehow knew the ins and outs of keg technology. He had a patch and a scientist looking jacket, so he must have known something. In the bar that I worked, it wasn’t added at the tap, it was added _immediately after_ it left the keg. Out of the keg, it immediately went into the weirdo looking doohickey that mixes it all up and pumps it to the tap. Maybe there are other ways to do it and **Omniscent** is dead on. Which could also explain your aversion to keg Guinness, **Tapswiller**. Maybe the bar your were at, or wherever it was you had the funky Guinness, the tap system wasn’t up to par? Or, it wasn’t up to the standards of the special guy we had come in and setup the bar where I had worked? Because I never had a sole complain about our Guinness on tap. And we sold a bunch of it too, outside of the sixty-five other tapped beers. ---
**Author:** ![CaelNCSU](https://avatars.discourse-cdn.com/v4/letter/c/c89c15/32.png) [@CaelNCSU](https://boards.straightdope.com/u/CaelNCSU)\ **Post date:** [September 20, 2001, 8:00am UTC](https://boards.straightdope.com/t/beer-is-guiness-by-the-keg-nitrogenated/82629/13 "2001-09-20T08:00:44Z")
So why doesn’t it carbonate in the keg during priming? ---
**Author:** ![pulykamell](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pulykamell/32/3166_2.png) [@pulykamell](https://boards.straightdope.com/u/pulykamell)\ **Post date:** [September 20, 2001, 1:15pm UTC](https://boards.straightdope.com/t/beer-is-guiness-by-the-keg-nitrogenated/82629/14 "2001-09-20T13:15:40Z")
According to the Guiness Website, the Draught Guiness in Ireland should be the same as the Draught Guiness in England and elsewhere in the world. I’m not sure I buy that, as I’m fairly certain the Guinesses around Europe taste different, but according to the site a blind taste test was done with beer snobs, and nobody could tell the difference. ---
**Author:** ![Ferrous](https://avatars.discourse-cdn.com/v4/letter/f/8e7dd6/32.png) [@Ferrous](https://boards.straightdope.com/u/Ferrous)\ **Post date:** [September 20, 2001, 3:49pm UTC](https://boards.straightdope.com/t/beer-is-guiness-by-the-keg-nitrogenated/82629/15 "2001-09-20T15:49:27Z")
Glad to see no one called me on this while I was away… > [@](#): > > Many large breweries (Coors being a notable exception) pasteurize anyway because it simplifies the removal of yeast and increases shelf life. If you don’t pasteurize, the filtering process is more complicated (therefore expensive). Turns out this is not correct. I was right about the shelf-life factor, but pasteurization has nothing to do with yeast removal. Y’see, I post at the office (beats working, right?), and so don’t have access to my books. When I got home and looked it up, I discovered my mistake. FTR, the process goes:filter, carbonate, pasteurize. > [@](#): > > _Originally posted by CnoteChris_ > Which could also explain your aversion to keg Guinness, **Tapswiller**. Maybe the bar your were at, or wherever it was you had the funky Guinness, the tap system wasn’t up to par? Or, it wasn’t up to the standards of the special guy we had come in and setup the bar where I had worked? Could be. I’d certainly be willing to give it another chance. Wouldn’t want to neglect a perfectly good beer. **escapol** and **pulykamell** , I don’t know if there is any difference between Guinness in the UK and in Ireland, but I have read that the Guinness that is exported outside GB is different. Specifically, it is higher in alcohol. Apparently the Brits have some weird graduated tax structure that taxes more for more alcohol content. Supposedly the local stuff is made to fall in a lower tax bracket. ---
**Author:** ![Omniscient](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/omniscient/32/3290_2.png) [@Omniscient](https://boards.straightdope.com/u/Omniscient)\ **Post date:** [September 20, 2001, 5:20pm UTC](https://boards.straightdope.com/t/beer-is-guiness-by-the-keg-nitrogenated/82629/16 "2001-09-20T17:20:42Z")
Having drank my share of Guinness in hundreds of US bars of varying quality, dozens of Irish pubs in Dublin, and straight from the source at the St Johns Gate Brewery, I’d say there is very little discernable difference between the tapped versions. Any major difference is likely a matter of legend and placebo, but the tax policy Tapswiller mentioned seems plausible, it however might be a thing of the past as well. This is not to say that all Guinness tastes the same, it certainly does not. If you beleive Guinness at the Dubliner on Temple Bar tastes better than at the local TGIFridays, its probably because it fresher. The effect being even more noticable at pubs which don’t sell much Guinness. > [@](#): > > Out of the keg, it immediately went into the weirdo looking doohickey that mixes it all up and pumps it to the tap. This is true, and while I’m not a brewmeister or tap building technician, its not the ideal method. The reason it is better to inject the nitogen at the tap is because there is usually a half pitcher or so of beer resting in the lines between the cooler and the tap. Presuming you’re in a bar where Guinness is served only occasionally, the odds are that a given pour will be somewhat flat due to the fact that the nitrogen was injected minutes, hours or even days between this and the last pour. If you’re in a pub running a Guinness promotion, or which just happens to sell alot of Guinness the point is moot. > [@](#): > > So why doesn’t it carbonate in the keg during priming? Guiness is filtered before it is kegged just like most other macrobrews. Since it’s filtered there is no yeastin the beer to digest the remaining sugars. The yeast’s digesting is what creates the carbonation. Most macrobrews use the same process but simply pump mechanically CO2 into the kegs after they are kegged. Guinness simply omits this step leaving it to the bars to do. this is why Guinness isn’t servered as commonly as most other beers of its popularity, its expensive of the bars to set up the nitrogen tap system. And to keep your defintions straight, priming is when they add a bit of sugar to the beer before bottling to give the remaining yeast something to digest into CO2, presuming that most of the malt has been consumed. You generally will never prime a beer which has been filtered. In short, if you filter a beer, it won’t carbonate any longer except by purely mechanical means.