# If you can light a fart, can you light a burp? **URL:** \ **Category:** Factual Questions\ **Created:** [June 21, 2013, 4:50am UTC](https://boards.straightdope.com/t/if-you-can-light-a-fart-can-you-light-a-burp/661537 "2013-06-21T04:50:27Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![Patch](https://avatars.discourse-cdn.com/v4/letter/p/a183cd/32.png) [@Patch](https://boards.straightdope.com/u/Patch)\ **Post date:** [June 21, 2013, 4:50am UTC](https://boards.straightdope.com/t/if-you-can-light-a-fart-can-you-light-a-burp/661537/1 "2013-06-21T04:50:27Z")
Thinking about it today, if the methane in bovine burps are contributing to global warming, is there enough methane in the Bessie’s belch to ignite? If you’re wondering how one goes about this, imagine Bessie is a bored college student with lots of peer pressure. ---
**Author:** ![Isilder](https://avatars.discourse-cdn.com/v4/letter/i/cc9497/32.png) [@Isilder](https://boards.straightdope.com/u/Isilder)\ **Post date:** [June 21, 2013, 9:20am UTC](https://boards.straightdope.com/t/if-you-can-light-a-fart-can-you-light-a-burp/661537/2 "2013-06-21T09:20:30Z")
No. Burps are air swallowed, or CO2 (eg from soda , or perhaps from HCl + carbonate reaction.) If it was methane, it would be as smelly as a fart… Since a burp is never as smelly as a fart, its not the product of 24 hours stewing at body temperature… There’s two sphincters (at each end of the stomach) preventing gas coming back the wrong way, and peristalsis is one way … if there is gas you get sore where the peristalsis is going into overdrive. ---
**Author:** ![Iggy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/iggy/32/3364_2.png) [@Iggy](https://boards.straightdope.com/u/Iggy)\ **Post date:** [June 21, 2013, 10:58am UTC](https://boards.straightdope.com/t/if-you-can-light-a-fart-can-you-light-a-burp/661537/3 "2013-06-21T10:58:24Z")
While humans may not have much methane in a eructation, [cows certainly do](http://en.wikipedia.org/wiki/Belching#In_other_animals) producing upwards [250 to 500 liters](http://www.ncbi.nlm.nih.gov/pubmed/8567486) of methane per cow per day. But methane is [only flammable at certain concentrations](http://boards.straightdope.com/sdmb/showthread.php?t=694404), about 5-15%, in air. Too little and there is not enough fuel. Too much and not enough oxygen in the mix. It might be difficult to get the right mix to light a cow burp on fire, but [no problem setting cow farts on fire](http://www.youtube.com/watch?v=5XYiC6n0CCk). ---
**Author:** ![Exapno\_Mapcase](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/exapno_mapcase/32/1051_2.png) [@Exapno\_Mapcase](https://boards.straightdope.com/u/Exapno_Mapcase)\ **Post date:** [June 21, 2013, 11:54am UTC](https://boards.straightdope.com/t/if-you-can-light-a-fart-can-you-light-a-burp/661537/4 "2013-06-21T11:54:06Z")
> [@Isilder](#): > > If it was methane, it would be as smelly as a fart… For the one millionth time, methane is odorless. ---
**Author:** ![CookingWithGas](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cookingwithgas/32/485_2.png) [@CookingWithGas](https://boards.straightdope.com/u/CookingWithGas)\ **Post date:** [June 21, 2013, 1:29pm UTC](https://boards.straightdope.com/t/if-you-can-light-a-fart-can-you-light-a-burp/661537/5 "2013-06-21T13:29:20Z")
> [@Isilder](#): > > If it was methane, it would be as smelly as a fart… Since a burp is never as smelly as a fart, its not the product of 24 hours stewing at body temperature.. The smell is caused by [sulfur compounds](http://www.salon.com/2013/04/07/passing_gas_a_modern_scientific_history/). > [@Mary Roach in "Gulp: Adventures on the Alimentary Canal"](#): > > Curious as to which olfactory notes the different sulfur gases contributed to the overall bouquet of flatus, Levitt purchased samples of the three gases from a chemical supply house. The judges agreed on the following descriptors: “rotten eggs” for hydrogen sulfide, the gas with the strongest correlation to stink; “decomposing vegetables” for methanethiol; and “sweet” for dimethyl sulfide. ---
**Author:** ![Patch](https://avatars.discourse-cdn.com/v4/letter/p/a183cd/32.png) [@Patch](https://boards.straightdope.com/u/Patch)\ **Post date:** [June 21, 2013, 11:13pm UTC](https://boards.straightdope.com/t/if-you-can-light-a-fart-can-you-light-a-burp/661537/6 "2013-06-21T23:13:25Z")
> [@Iggy](#): > > While humans may not have much methane in a eructation, [cows certainly do](http://en.wikipedia.org/wiki/Belching#In_other_animals) producing upwards [250 to 500 liters](http://www.ncbi.nlm.nih.gov/pubmed/8567486) of methane per cow per day. > > But methane is [only flammable at certain concentrations](http://boards.straightdope.com/sdmb/showthread.php?t=694404), about 5-15%, in air. Too little and there is not enough fuel. Too much and not enough oxygen in the mix. So there’s a chance a cow can enjoy a good cigarette without risk of doing a dragon imitation? ---
**Author:** ![Don\_t\_Panic](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/don_t_panic/32/398_2.png) [@Don\_t\_Panic](https://boards.straightdope.com/u/Don_t_Panic)\ **Post date:** [June 21, 2013, 11:42pm UTC](https://boards.straightdope.com/t/if-you-can-light-a-fart-can-you-light-a-burp/661537/7 "2013-06-21T23:42:43Z")
> [@Patch](#): > > So there’s a chance a cow can enjoy a good cigarette without risk of doing a dragon imitation? A bovine flame thrower would have been an \*awesome \*medieval weapon of war, though.