If someone forced me to pick a fruit I couldn't bear to live without, I would choose tomatoes in a heartbeat. (Yes, I said "fruit": although culinarily used as a vegetable, botanically tomatoes are actually fruit. More on this later.)
It's not just me who couldn't live without them -- I can think of many cuisines that would be vastly different without the lovely, delicious tomato, including Italian, French, Spanish, Portuguese, Greek, Mexican, American, Indian, Thai and Middle Eastern of all stripes. Pretty amazing that a fruit that left South America only a couple of centuries ago has charmed its way into the cuisines of so many cultures.
In my Brooklyn community garden, the first cherry tomatoes have started peeking through their tangled foliage. Every year, I'm amazed by how sprawling and gigantic my tomato plants get, even with (sort of) careful maintenance and staking. This year, I'm growing heirloom black and red cherries, along with yellow pear -- not to mention Cherokee Purple, German Pink and Brandywine non-cherry varieties. At the height of summer and into early fall, my family eats tomato, mozzarella and basil salad more than I'd care to admit (especially on the sweltering 100+ degree days we've been having recently in NYC). It's certain: I couldn't stand to be without tomatoes -- both in the garden and in the kitchen.
Tomatoes are native to western South America, where their ancestor was a teeny wild cherry variety. It is unclear whether tomatoes were first cultivated in Peru or in Mexico, but it is known that the Aztecs grew them along with tomato relatives tomatillos and chile peppers. From Mexico, tomatoes spread to Spain in the sixteenth century, where they hardly caught on like wildfire. Europeans were wary of tomatoes for another couple hundred years, apparently due to their botanical family connection to nightshades -- several of which can be deadly. Tomatoes weren't accepted as good eating until the seventeenth and eighteenth centuries, with Spain and Italy leading the way for future tomato world domination. (The British were a little late to the game -- they didn't catch on to the tomato's virtues until the end of the nineteenth century.) According to the Oxford Companion to Food, the first printed recipe for a tomato-containing dish is from a seventeenth century Neapolitan cookbook, Lo scalco alla moderna ("The modern steward"). The recipe is for "Tomato Sauce -- Spanish Style," and is easily recognizable as the very first printed recipe for marinara sauce.
The Spanish spread the tomato to the rest of the world, including to their Caribbean colonies and to the Philippines, where the fruit then spread to Southeast Asia, and finally to the rest of Asia. The Spanish are probably also responsible for the introduction of the tomato in North America, having cultivated the plant in their colony of Florida. By the end of the nineteenth century, tomatoes were being canned in Italy and in the United States in vast quantities. Tomato ketchup, that most American of condiments, began to be produced commercially in the US by the 1830s.
Tomatoes are in the Solanaceae (nightshade) family and boast some pretty important relatives, including potatoes, peppers, eggplants, ground cherries (a.k.a., cape gooseberry), tomatillos and tobacco. Because tomato seeds are contained inside the swollen ovary of the plant, they are classified as a fruit rather than a vegetable. There are many, many varietals of tomato, from the tiniest cherry to the grandest heirloom. Each requires ample sunlight and a great deal of water.
China now leads the way in the global production of tomatoes, followed by the US, India and Turkey. California and Florida dominate the US production of tomatoes.
In the US, tomatoes are grown in vast monoculture expanses of industrial farmland in California and Florida, and increasingly, in Mexico. Herbicides, fungicides and insecticides are used extensively in industrial tomato production, including the dangerous pesticide endosulfan, commonly used in Florida tomato production, which, according to the US Environmental Protection Agency, poses "unacceptable health risks to farm workers and wildlife and can persist in the environment." Even with these "unacceptable" risks, endosulfan will not be phased out of Florida tomato production until December 2014. The Environmental Working Group's 2012 Shopper's Guide to Pesticides in Produce lists tomatoes at number 29 (out of 49 ) for pesticide residue. (See our vegetable rule of thumb.*)
The very first genetically modified organism (GMO) food marketed for human consumption was the goofily named "Flavr Savr" tomato, first sold in 1994. The genetic modification of the Flavr Savr was designed to slow softening of the fruit, theoretically allowing the tomatoes to be picked ripe on the vine and then transported. Industrially produced tomatoes are picked hard and green, then artificially ripened using ethylene gas. (Vine-ripened tomatoes are far too delicate to be shipped across the country.) Flavr Savrs didn't catch on, and no GMO tomatoes are currently on the US market.
There have been several multi-state outbreaks of salmonella involving tomatoes, with the likely culprit contaminated irrigation water. This article explains how salmonella, once a disease confined to animal products, can contaminate produce.
Even organic tomatoes are causing environmental problems, especially in Mexico, where they are grown primarily for export to the US. As this article explains, organic tomato production is seriously depleting local water tables and hindering local subsistence farmers' ability to grow food to feed their families.
Finally, although not an "environmental" concern per se, the conditions of the workers who pick tomatoes in the US is deplorable. In addition to the risks of pesticide exposure, tomato pickers in Florida often live in what has been described as "modern slavery," as this article discusses. In Immokalee, Florida (where most US winter tomatoes come from), a group called the Coalition of Immokalee Workers has been working to change the way workers are compensated and treated, as our own Leslie Hatfield discusses in this post (with video!).
Although tomatoes are available year-round due to the preponderance of hothouse varieties, in most places in the US the very best tomatoes are found at the market in summer and early fall. In fall, also look for a glut of green tomatoes, as farmers frequently harvest the green fruit before the first frost, knowing that they won't fully ripen in the cool weather.
Tomatoes are low in calories, high in fiber and high in both vitamins C and A. They are also good sources of vitamin K, potassium and manganese. As you might have guessed from the tomato's taxonomic name, Solanum lycopersicum, the fruit is also very high in lycopene, an antioxidant that has preliminarily been linked to cancer prevention, especially prostate cancer. Tomatoes are also rich in flavonoids, antioxidants with anti-inflammatory and anti-bacterial properties. Interestingly, organic tomatoes have been found to have higher levels of flavonoids than conventionally grown varieties.
Tomatoes come in a wide variety of shapes and colors, including purple, yellow, orange, and red. There are striped varieties of the fruit, as well as tomatoes that stay green even when ripe. For all tomato types, look for fruit that is unblemished and free from bruised or soft spots. The fruit should be firm to the touch when (gently) squeezed.
Keep your tomatoes on the counter rather than in the refrigerator, as refrigeration causes the fruit to become mealy. (The exception to this rule is small cherry tomatoes, which I've found to be fine stored in the fridge.) Tomatoes continue to ripen after being picked, so keep this in mind when selecting tomatoes at the market. If you are not going to use them for a couple of days, choose fruit that are on the firmer side and allow to ripen on the counter. Cherry tomatoes will keep for over a week if stored in the refrigerator.
To quickly peel a large batch of tomatoes, for sauce-making or canning, score a very shallow "X" in the base (non-stem) end of the tomato with a sharp pairing knife. Drop in boiling water for 10 to 15 seconds, and then place in an ice bath (a mixture of ice and water) to cool. The skins will then slip off easily. (And don't throw away the skins -- they make a great addition to vegetable stock!)
Tomatoes are extremely versatile in the kitchen and shine in many dishes, from sauces to salads to condiments. They are equally tasty raw and cooked, and can be stuffed, sautéed, roasted, dried, pickled (especially green tomatoes) or fried. Their natural culinary mates are other members of the nightshade family, including peppers (both hot and sweet) and eggplant. The fruit also is delicious paired with eggs, cheese, red meat and fatty fish such as tuna. Other classic culinary combinations include pairing tomatoes with onions, garlic, basil, oregano and parsley. Tomato paste is a kitchen staple used in sauces, stews and other dishes.
When tomatoes are at the peak of their beauty and ripeness, try this delicious, dead-simple recipe adapted from Marcella Hazan's Essentials of Classic Italian Cooking. The garlic and the vinegar bring out the sweetness in the tomatoes, and the juices created from the salad cry out for chunks of good, crusty bread to sop them up.
4 to 5 garlic cloves
2 tablespoons good-quality red wine vinegar
2 pounds fresh, ripe tomatoes (either round or plum)
12 fresh basil leaves, washed and dried
Extra virgin olive oil
Peel the garlic cloves and mash them with the flat side of a large chef's knife (or alternately, with the back of a small, heavy pot).
Put the mashed garlic in a small bowl together with the vinegar and 1 to 2 teaspoons of salt. Stir and let steep at least 20 minutes (and up to an hour).
Using a swivel-blade peeler, skin the raw tomatoes. (See Note, below.)
Cut the tomatoes into thin slices, and spread out in a deep plate or platter.
Tear the basil leaves into 2 or 3 pieces each (or leave whole if small) and sprinkle over the tomatoes.
Pour the vinegar mixture through a wire strainer over the tomatoes and basil, distributing the vinegar over the salad evenly.
Add enough extra virgin olive oil to coat the tomatoes well.
Taste and correct for salt and vinegar. (A couple of grindings of fresh pepper wouldn't be out of place here, either.)
Note: If you do not have a swivel-blade peeler, get one! They are quite useful in the kitchen. Barring that, you can use the blanch-and-peel method described in "pro tips" above, but note that the texture of the blanched tomatoes won't be quite as good as raw.
(*Vegetable rule of thumb: We think that first and foremost, in terms of nutrition, people should eat lots of fruits and vegetables whether they are organic or not. The EWG's guide is a handy list, but we will point out here that the impacts of pesticides are not limited to your ingestion of them -- agricultural chemicals also affect farmworkers and local waterways, both good reasons to buy organic, even those vegetables that carry a light pesticide load. Also, it has been demonstrated that produce grown by small-scale farmers, even those who are not certified organic, tends to have a lighter pesticide load than its industrially-produced counterpart, owing to industry's tendency toward large monocrops.)
Image "Tomatoes" by Jeremy Keith on Flickr used under a Creative Commons Attribution-NoDerivs 2.0 Generic license.