The popular phrase, "I have nipples, Greg, could you milk me?" from the 2000 movie "Meet the Parents", is similar to the widely held belief that tomatoes, because of their seeds, are really fruits instead of vegetables.

Botanically, tomatoes are fruits but cucumbers, zucchini, pumpkins, nuts, corn, peppers, peas, and other vegetation that may not seem like it also fit into this fruity category.

Botanists define fruit as any part of a plant that contains both its seed and the ovary that produce that seed. However, of all the botanically fruity plant pieces we commonly call 'vegetables', tomatoes are one food with an especially controversial history of classification.

The 1893 United States Supreme Court Case Nix v. Hedden addressed the Tariff Act of March 3, 1883 requiring a tax on imported vegetables but not fruit. Tomato growers argued strongly that tomatoes should not be taxed. The court used definitions of fruit from Webster's Dictionary, Worchester's Dictionary and the Imperial Dictionary to narrow down a label for the tomato.

In the present day, tomatoes are utilized in dishes on the sweeter tasting side like the recent recipe highlighted in the New York Times for tomato preserve ice cream by Maria Hines, owner of the Seattle based Tilth restaurant. Thanks to chefs like Hines tomatoes are now living up to their fructificative label.

In Nix v. Hedden, however, the battle was not so sweet. In addition to definitions for the word tomato, the court looked up definitions for pea, egg plant, squash, cucumber, pepper, potato, turnip, parsnip, cauliflower, cabbage, carrot and bean.

As a result, the court ruled in favor of the tomato's vegetable classification, despite its seeds.

Justice Horace Gray wrote the statement for the court. "These definitions have no tendency to show that tomatoes are 'fruit,' as distinguished from 'vegetables,' in common speech, or within the meaning of the tariff act."

Steve Toso, Sous Chef at the Italian food oriented Biba Restaurant in Sacramento, doesn't hesitate to call tomatoes a fruit. Toso, who has been with the restaurant for over a year and a half estimates his tomato use during peak season—especially in the summer months—averages about fifteen pounds per day.

Though Toso says he does not use fresh tomatoes when they are out of season he does cook with a similar canned item he labels a vegetable, more commonly known as canned Roma tomatoes. The difference, he says, between fresh, mildly sweet tomatoes he buys from farms in the Yolo County area and canned ones from Italy is flavor.

According to the Director of the Tomato Genetics Research Center at U.C. Davis, Roger Chetelat, the different references to tomatoes regarding its fruit or vegetable status are insignificant in the big picture.

Chetelat, who has worked for Campbell's Soup, says tomatoes are interesting because just as they are not just fruits or vegetables they are also just not one plant. "Tomatoes have 9-13 species which are a window into a fascinating group of plants."

At the moment, the big breakthrough in the tomato world, at least at the U.C. Davis research center has to do with crossing tomato species. In the past the 9-13 cross compatible varieties were bred to create disease and insect resistance as well as nutritional properties.

The challenge in making new cross varieties, Chetelat says does not have a complicated explanation. Biologically, he says, some species simply can't be expected to cross. "Our overall theme is to increase accessibility of wild species and decide what crosses you can make and what you can cross and can't cross."

All the cross breeding and cross references can get confusing. The veggie-fruit has also been grafted to a potato. The tomato-potato described as growing tomatoes on top and potatoes on the bottom is listed for $6.98 on the Gardeners' Choice website based out of Hartford, MI.

The classification and modification of tomatoes, as with the tomato-potato, may leave tomato-sauce loving, ketchup addicted, tomato bisque ordering individuals with some food for thought and a side of confusion.