Having eaten a couple of meals with baked beans in over the weekend, my poor husband has tummy ache and of course wind.
I am led to believe that ‘wind’ is a large part of the global warming problem, but where does the methane come from? Maybe it’s in the beans? but…
cows, for instance, only eat grass, and then produce methane,
Is it in the grass?
Please keep it clean I don’t want to have my knuckles rapped. 
It’s a byproduct of digestion. Our systems
break down food into smaller components.
Some of these are useful to us (vitamins,
water, protein, etc.) and these are sent
to our cells. Some are not (insoluble fiber,
methane, etc.) and these are excreted.
I don’t know about people, but in cows
the methane is produced by the bacteria
in the cow’s stomach that help with the
cow’s digestion.
http://animals.howstuffworks.com/mammals/methane-cow.htm
If we could just get rid of all the termites and wetlands than methane production could be greatly reduced. That’s why Monsanto should be given license to run the world. Benjamin Franklin’s “notorious” essay to the Royal Academy on Farting Proudly is worth a read. Some said it was “scarcely worth a Fart-hing.”
The exact details of the process are still being studied, and more information may allow scientists to reduce cows’ methane output.
I, and obviously the scientists, don’t know exactly where the methane comes from. It can’t just be magic’d into existence. Alchemy or what?
I believe an adequate answer was put forward. Here’s something from the USEPA,
Methane (CH4) is emitted from a variety of both human-related (anthropogenic) and natural sources. Human-related activities include fossil fuel production, animal husbandry (enteric fermentation in livestock and manure management), rice cultivation, biomass burning, and waste management. These activities release significant quantities of methane to the atmosphere. It is estimated that more than 60 percent of global methane emissions are related to human-related activities (IPCC, 2007:a ). Natural sources of methane include wetlands, gas hydrates, permafrost, termites, oceans, freshwater bodies, non-wetland soils, and other sources such as wildfires.
These activities release significant quantities of methane
Yes but from where?
Take the cow thing as their diet is pretty straightforward.
The cow is born - does it contain methane? It eats grass - does that contain methane? It uses bacteria to break down the grass - does the bacteria contain methane?
Does the cow absorb methane through it’s skin?
Where does so much methane come from? It can’t just appear, it must be mixed with something somewhere and then released by “these activities”
In cows it is a by product of digestion just like your own Farts. My very own ancient puppy is resting on my feet as I write this, every few seconds I hear a toot. I’m lucky I’m conscious.
Cows use gastrointestinal bacteria to digest the otherwise indigestible cellulose of their plant food cell walls. This particular process yields methane. We eat plants too, but humans don’t digest the cellulose cell walls-- we only get nutritive value from the plant materials released by chewing.
Now in the case of beans and some other vegetables, our methane comes from the breakdown of certain compounds called oligosaccharides. These are short chains of simple sugars such as fructose. We can only partially digest oligosaccharides, and the undigested portions serve as food for our gastrointestinal flora and one product of this process is methane.
In other words, methane is bacteria poo.
Well some of that poo is eaten by other bacteria that produce poo that in turn is eaten by other bacteria that produce poo that in turn… The English have used poo gas for street lighting like since forever.
It’s rather disconcerting to realise I’m a toilet.
Garbage in garbage out.
Bacterium: “What is this? It tastes like crap.”
Other bacterium: “Well, duh. Just shut up and eat, already. We’ve the neighbors to feed, you know.”
Better watch out, Methane has carbon in it! 
Blushing is a telltale sign of flushing.
I’m still trying to figure out why I gotta worry about the carbon.
It’s Chemistry’d into existence. “Methane” is
the name we give the molecule CH4, which
means there is one carbon atom bonded to
four Hydrogen atoms. Carbon and Hydrogen
atoms are in us and the food we eat and the
bacteria in our digestive systems, but those
atoms are bound up in other molecules, like
glucose and DNA. So, the methane isn’t in
the grass the cows eat, but the building
blocks to make the methane is.
We (or bacteria) use chemical reactions to
break down the large molecules in food into
other, smaller molecules that cells can use.
As a result of these chemical reactions, less
useful small molecules, like methane, are
created. Since we don’t have a use for those,
we have to excrete them.
It’s like saying “Is a bookcase in a tree?”
No, but the stuff to make a bookcase is in
the tree.
Good point. Or: “Hey. This isn’t a cake! It’s just sugar, flour, oil, baking powder and eggs! Where do cakes come from?”
Methane is an odourless, colourless, non-toxic gas, which is produced mostly as a result of anaerobic decay of organic matter. It is formed on or below the earth’s surface (and in the guts of animals) - it’s a constituent of natural gas, found with oil deposits - and once it’s released into the atmosphere it gets into the upper regions by convection, mostly at the tropics. It is a very potent greenhouse gas, each molecule having many times the heat-trapping potential of that of a carbon dioxide molecule. Oxygen and water vapour are the enemies of methane, and the gas gradually breaks down in the atmosphere by oxidation processes. The amount of methane in the atmosphere has risen dramatically in the last couple of hundred years. Human contributions are mostly to blame, landfill sites and the proliferation of herbivorous farm animals being significant culprits. Any other process of decay that excludes oxygen is also likely to produce methane, even your compost heap, so things such as slurry lagoons, silage heaps and manure dumps will contribute significantly. The odour of a nice ripe fart is nothing to do with the methane present. You need to look in the direction of various sulphurous compounds to explain that. And I should add that methane cannot be regarded as an excretory product of humans or farm animals, any more than dietary fibre can, as it is not produced by metabolic processes within cells.
I remember seeing in Science, probably about 15 years ago, that some people (and presumably other mammals) have gut flora that produce hydrogen instead of methane. IIRC, these folks had lower rates of some types of cancer due to the extreme anti-oxidant properties of hydrogen. There was also some talk about trying to introduce those microbes into cows to reduce the amount of methane produced by ranching. I haven’t heard anything since.