Just a random craving? Not necessarily, says Robin Dando, Cornell University assistant professor of food science. The high decibel level in the cabin interferes with how people perceive taste. The palate registers sweets such as soft drinks less intensely, while the taste known as umami is heightened. Thirsty passengers may find they yearn specifically for something rich and savory, and they frequently choose tomato juice. In fact, the German airline Lufthansa estimates people consume about as much tomato juice as beer aboard its flights.