Over the last hundred years, tomatoes have been bred for hardiness in a variety of climates, and today commercial crops are cultivated in every state. Local growers supply tomatoes to every region of the country in season, mainly summer to fall. Out of season, most tomatoes grown in the US are shipped from Florida or California, or cultivated in a hothouse. Of course, many of the tomatoes Americans eat are home grown. The tomato is the number-one vegetable favored by backyard gardeners.
There are thousands of tomato varieties, but most fall into one of the following categories:
Beefsteak tomatoes: These large tomatoes are up to 6 inches in diameter and are extremely “meaty.” In other words, they have a high flesh-to-seed ratio. Prized by home gardeners, beefsteaks are only seasonally available. A distinguishing characteristic of some beefsteaks is an odd puckering or scarring at the blossom end known as “cat facing.”
Cherry tomatoes: Round and bite-sized, these tomatoes are often served in salads and as garnishes. Their skin may be red or yellow. Varieties of “heirloom” cherry tomatoes are sometimes available at specialty food markets.
Currant tomatoes: The tiniest of the species, these tomatoes grow in clusters and measure only about 3/4 inch in diameter. They are available in both red and yellow varieties and have a sweet, crisp flesh.
Grape tomatoes: Now widely available in supermarkets, these sweet, firm-textured, grape-shaped tomatoes are slightly more elongated than cherry tomatoes. Because they don’t have as much juice as cherry tomatoes do, “squirting” accidents are minimized.
Heirloom tomatoes: About 25 years ago some dedicated individuals began saving what they could of the remaining open-pollinated (without human intervention) seed varieties of tomatoes. These have become known as “heirloom seeds.” An increasing number of growers are now using these seeds to produce an extensive array of heirloom tomatoes. Notable for their intriguing coloration (ranging from white to black, and yellow- or pink-striped to variegated), as well as their often amusing names (Mortgage Lifter, Box Car Willie, White Wonder, to name a few), these tomatoes are also prized for their excellent flavor. Because they are thin-skinned and fragile, they don’t ship well and are therefore not available in most supermarkets. Look for them at specialty food stores and farmers’ markets during tomato season. Use them soon after purchase for the best flavor.
Pear tomatoes (teardrop): These small, pear-shaped tomatoes (about the size of cherry tomatoes) have an intense, sweet-tomato flavor. There are red and yellow versions available.
Plum tomatoes (Italian, Roma): These egg-shaped tomatoes are meatier and less juicy than slicing tomatoes, and are therefore ideal for making sauces and adding to other cooked foods. They are also the type most commonly used for making sun-dried tomatoes and canned whole tomatoes.
Slicing (round) tomatoes: This is an umbrella term for medium-to-large tomatoes, including the globe varieties usually found in supermarkets.
Yellow or orange tomatoes: These are sometimes advertised as “low-acid” tomatoes. But, in fact, they are not lower in acid than other tomatoes. Rather, they’re higher in sugar, which produces a very mild, sweet flavor. Like red tomatoes, these have plenty of vitamin C and potassium, but they don’t have lycopene.
When you can’t find flavorful fresh tomatoes, you may be better off relying on prepared tomatoes and tomato products. Canned tomato products are sold in vacuum-packed boxes as well as cans and jars. Dried tomatoes are sold loose, in plastic bags, or immersed in olive oil in jars. The dried tomatoes sold are almost invariably “sun-dried” tomatoes. This is essentially a marketing ploy—whether tomatoes are dried by the sun, a dehydrator, or a home oven doesn’t really affect their flavor.
In general, canned tomatoes are designated “solid pack” (which means no liquid has been added) or packed in tomato juice, puree, or paste. The label will indicate the packing medium. Salt or other flavorings, such as bay leaf or basil, may also be included. Canned tomatoes with added salt may have twelve times the sodium of unsalted tomatoes, so be sure to check the ingredients list on the label. Salt-free brands don’t necessarily have the words “no salt added” prominently displayed. The following are the tomato products most commonly found in the market:
Whole tomatoes: Often the plum or Roma variety, these are mature whole tomatoes that have been cooked, peeled, and cored. Most whole canned tomatoes are solid pack.
Diced tomatoes: These tomatoes are excellent for stews and chunky pasta sauces. Most are packed in tomato juice or purée. Many have calcium chloride added to prevent the tomatoes from turning mushy.
Crushed tomatoes: Similar to diced but the pieces tend to be less uniform in size.
Stewed tomatoes: Tomatoes are labeled stewed when they are mixed with other vegetables (onion, green pepper, celery, for example) and seasonings such as oregano, thyme, and sage.
Tomato puree: A concentrated form of tomato juice and tomato pulp, puree has the consistency of a thick tomato sauce, and may contain salt.
Tomato sauce: This product is the same as tomato puree, except that the sauce has been seasoned. Be sure to read the labels; some brands have whopping amounts of sodium added. There are also a huge variety of tomato-based pasta sauces on the market, and the added fat and sodium levels in some brands can be sky-high. One popular brand of marinara sauce gets 40 percent of its calories from fat and contains nearly 800 milligrams of sodium per 1/2-cup serving. Brands with added cheese or meat can be even higher in fat and sodium.
Tomato paste: This very concentrated form of tomatoes is sold in cans or in tubes. By law, tomato paste must be concentrated to more than 24 percent solids (compared with 8 to 24 percent for tomato puree).
Sun-dried tomatoes: These are plum tomatoes that have been dehydrated to preserve them and intensify their flavor. They are sold packed in oil or dry. The tomatoes that are not packed in oil are usually reconstituted by soaking in hot water before being used in cooking. Most often sun-dried tomatoes, like other dried fruits, are treated with sulfur dioxide to preserve their color and prevent rotting. People with sensitivity to sulfites—notably some people with asthma—should only consume dried tomatoes made without sulfur dioxide.