The Tomato is a food in all of the installments of the Creatures series of games.
In Creatures 1 the tomato is classed as a herb, and though it's not very satisfying nutritionally, it has aphrodisiac qualities, having the following effects:
Compare with Ugly Tomato.
In Creatures 2, the Tomato Plant bears fruit which do not have any reproductive effects.
Tomatoes are available for C3/DS through several third party agents, including the Albian Fruit Basket and the Terra metaroom. These Tomatoes are almost identical in appearance and effect to the C2 versions they are based on.