Desert-grown grain is an item obtained by searching the sack next to the Bank Camel in the Tombs of Amascut raid lobby. According to her, the grain is specially grown in the Kharidian Desert and goes through a preparation process of several years, and as a result doesn't taste too salty with "just a hint of sweetness".
Though the camel will commonly catch the player in the act while searching the sack, players who manage to obtain one can feed it to her for some humorous dialogue if wearing a camulet.