Simply put, orange tomatoes are tomatoes which are orange, rather than the more conventional red. When people talk about orange tomatoes, they are either referring to certain heirloom tomato varieties which are orange in color, or to a specially bred tomato varietal which has very high amounts of beta-carotene. In either case, the tomato might look a bit weird and certainly distinctive, with a bright orange exterior and an orange interior. However, orange tomatoes taste just like regular tomatoes, although they will of course produce orange ketchup, tomato sauce, and juice blends.
In the world of heirloom tomatoes, tomatoes come in a lot of colors. In addition to classic red, heirlooms also come in orange, yellow, green, and purple. It is also not uncommon to see tomato varietals which are streaked with multiple colors. Some famous heirloom orange tomatoes include: Dad's Sunset, Golden Jubilee, Orange King, Sweet Orange, Patio Orange, Dr. Wyche's Yellow, and Yellow Brandywines. Each of these varieties has a distinctive appearance, texture, and flavor.
Orange tomatoes in the heirloom garden come in a range of sizes, from tiny cherry tomatoes to big, juicy beefsteaks. Many people like to grow heirloom tomatoes because they look unusual, and also because they tend to be packed with flavor, and the flavor is more complex and interesting than that of an ordinary red supermarket tomato. Orange tomatoes can be used in salads, juices, pizzas, sauces, and so forth, adding flavor and color. They also tend to be lower in acid than red tomatoes, which can be appealing for people who have been told to eat a low acid diet.
Orange tomatoes illustrate the incredible diversity of heirloom tomato varieties. If you think of tomatoes as insipid red vegetables piled up in the produce section or stuffed into cans, you haven't had an opportunity to see the range of colors, shapes, sizes, and flavors in the tomato world. A farmers' market or greengrocer is a good place to start when searching for new tomato varieties, and you can also try your hand at growing them at home, using seeds or sprouts which can be obtained from garden stores or heirloom tomato suppliers.
John R. Stommel, an agricultural researcher in Maryland, has produced a very special orange tomato varietal. His orange tomatoes are orange because they have an extremely high percentage of beta-carotene, the same substance which turns carrots and pumpkins orange. This substance is incredibly valuable in the human diet; Stommel hoped to make beta-carotene consumption easier with his orange tomatoes, which had not been released on the open market as of 2008, although they are likely to appear soon.