For some reason, we are conditioned not to eat blue food - which is why plasters for kitchen personal are blue - they would stand out if they appeared in a dish, because nothing else on the plate would be blue.
I remember reading about a chef who cooked for the team on a weather station at the North Pole. They were cut off for months at a time, so he baked bread for the team, and one day, for a change, be added some blue vegetable dye to the dough, and produced blue bread.
Despite his assurances that the bread would taste exactly the same, none of the crew would touch it.