It is really a question of preparation. You would be foolish to drink endless coffee when on Q or pre-flight. We were encouraged to eat low fat, no beans food before flight. In-flight sarnies were supposed to be bite size.
Of course some catering units, unused to aircrew rations could cock up in spades. In particular, bottles of undiluted squash, hard boiled eggs in shells, oranges, bananas (not much better), cups of tinned mixed fruit.