The YLOD on the PS3 is caused by "potato chipping" of the processor. It is a BGA (ball grid array), which is a chip that has rows of small balls on the bottom of the package. When the component overheats the corners start to lift up, which in an extreme case would start to look like a potato chip. When this happens the ball no longer makes an electrical connection between the chip and the PCB. There is no known fix for this other than replacing the BGA. The fixes on the internet, or offered by Sony, heat the chip up in the hopes the package straightens out. This allows it to make a weak electrical connection but it will not create a good solder connection again. Operating the Playstation in a damp enviroment will make the condition worse, or more likely to occur, because the moisture is absorbed into the chip while not running and when it heats up during operation the moisture cooks out and creates a condition known as "popcorning". Any fix other than replacing the BGA with a new one is temporary at best.
And yes,.....we electronics guys do think about food a lot.....