Many people travel to different places in the world by air.Usually it takes a long time，maybe half a day，for people to stay in the plane.So airlines （航空公司） give people food.But it is common that they feel bad about the food taste.To solve this problem，airlines try hard to improve their food.They would like to do so because they don't want to lose customers （顾客）.
However，according to some researches （调查），part of the reason why plane food tastes bad is that at high altitude （海拔） our body changes in a special way.That's why we cannot taste things as well as we do on the ground.Also，as the plane moves up，the air pressure （压强） inside the plane changes a lot，which makes our taste buds （味蕾） lose part of their feelings.So we think the food in the plane tastes bad.The sad fact，however，is that our noses have no idea.
All of these help to explain why airlines choose to give passengers very salty （咸的） and spicy （辛辣的） food.Without doing so，people inside the plane would find the food terrible.
Though airlines try their best，it is not as easy as they thought.Because they can't deal with the special environment successfully，such as the change in air pressure，making food taste good is still hard for them.
