Altitudes effect on taste Over dinner, some vegan friends of mine discussing plans to open a 5 star organic restaurant inside the cabin of an airbus A380. 

Exactly what I thought too! But they raised an interesting point: apparently the taste of certain foods changes depending on the altitude you consume it at. 

I looked into it a little and discovered lots of interesting facts about Heston Blumenthal cooking salmon and whatnot for astronauts, but not must hard-chemistry behind why our sense of taste depletes the higher in the atmosphere we go.   

So what causes such a taste discrepancy? Is it compounds within the food that "lose" their flavour, or it just our perception of taste that changes?
The difference in perception of taste is altered both by the lower air humidity as well by the lowered cabin pressure while on flight, the later typically kept to what corresponds to an altitude of about 2'400 m above sea level (source).

Regarding the actual changes in taste, BBC Future once nicely shed light on context, causes and outcome; in probably more accessible words than ongoing research articles like this about it.