What exactly happens to a Titan's body after it is killed? I just started watching the anime and I haven't read much of the manga so I don't know if it is explained further on.

We all know a Titan's body gives off extreme heat, from an encounter Eren had with the Colossal Titan and an episode where they learned this in class.

In episode 6, when Mikasa killed a Titan, we saw the body still giving off heat..



..and a few minutes later it was pretty badly burnt, unrecognizable in fact.



Later in episode 7 when Eren in his Titan form attacks another and beats it to a pulp, we see that the process has somewhat accelerated? At first I thought the body eventually burned away but this one was different than the first. All of the Titan's flesh was gone.





So, what exactly happens to a Titan's body structure after it is killed? Does the heat burn it up now that it cannot regenerate or what?
In episode 15, "Special Operations Squad: Prelude to the Counterattack, Part 2" where Zoe Hange has those 2 captured titans (which she named "Sawney" and "Bean"), she mentions that the Titans seem unusually light for how large they are, and that a severed arm of one of the titans weighed nothing, which allows such large bodies to move so quickly with great agility.

Though, at least so far in the anime and manga, there's no explanation to their physiology or what exactly happens after they die, it's probably the case that their solid state is being maintained by their mysterious "power source" and that once the source of power is gone (and thus cannot regenerate), their physical bodies (sans skeleton) return to the form of some type of gas.

So, to summarize this completely unsubstantiated speculation:


Titan's bodies are actually made up of some type of gaseous substance that weighs nothing
While alive, with its "power source", the gaseous substance takes on the form of solid flesh-like material, but still incredibly light
Without this "power source", the flesh returns to the gaseous state and evaporates.
This may or may not have to do with the extremely high body temperature that the titans have.