Tomatoes and Tomatillos: Salsa Essentials

Karen Hursh Graber

Mexican Kitchen

This is the time of year when outdoor entertaining gets into full swing, and one of the staples of this casual kind of dining is salsa. It is served with chips or crudités, or as an accompaniment to grilled meat, chicken or fish, and is indispensable with tacos.

The word salsa means “sauce”, and includes both raw and cooked sauces, some of which contain neither tomatoes nor tomatillos. But many of the salsas used as table condiments contain one or the other, and sometimes both. And since these two ingredients are New World natives, used in Mexico since pre-Hispanic times, they have long held a prominent place in the country’s cooking.

We are told that the Aztecs ate something they called tomatl, which translates from the Nahuatl as “a round and plump fruit.” In order to be more specific about these round, plump foodstuffs, they used the prefixes and suffixes of the language to differentiate between the types of tomatl. So the true tomato was called xitomatl (today’s jitomate) meaning a round, plump fruit with a navel, and the husk tomato, or tomatillo, was called miltomate, meaning a round, plump fruit that grew in the milpa, or cornfield. Though very similar in appearance, the true tomato and the husk tomato are members of two different botanical families.

The European colonists, however, shortened both of them to tomate, generating a certain amount of culinary confusion, and the husk tomato became known as tomate verde, the name used in today’s Mexican markets for cultivated husk tomatoes. (The word “tomatillo” is not used in Mexican markets.) Wild husk tomatoes, many of them not much bigger than large purple grapes, are still called miltomate.

The husk tomato, or tomatillo, a member of the Physalis family, was originally domesticated in Central Mexico, and was found in the late levels of the Tehuacan caves in Puebla, dating as far back as 825 A.D. Something described as “tomato tissue” in the same caves dated back to 800 B.C. The plant thrives at the high altitude of Central Mexico, and is used in sauces, stews and soups. The husk, which is the outer calyx of the flower that enlarges into a papery sheath around the fruit as it develops, must be removed before food preparation.

Unlike the husk tomato, the true tomato, a member of the Solanum family, originated in South America, though archeological evidence indicated that it was domesticated in Mexico and Central America. The seeds were probably spread by migrating birds, and anthropologist Sophie Coe suggested that “When it arrived in Mexico, the already existing tradition of Physalis (husk tomato) cultivation made it (the true tomato) a logical candidate for horticultural attention.” The tomato could grow in lowland places where the tomatillo did not do well, and thus filled an important culinary niche.

When tomatoes appeared on the 1550 tribute lists of food given to Don Juan de Guzman, the governor of the Coyoacan district, they were in equal amounts to that of chiles, suggesting that the culinary connection between the two dates back several hundred years. And the importance of tomatoes in Mexican cooking was the subject of several reports in the news media during the summer of 2006, when flooding in Sinaloa wiped out a significant portion of Mexico’s tomato crop and actually caused a measurable rise in economic inflation. Housewives interviewed on the news bemoaned the rise in tomato prices, declaring that they could not cook without them.

Although botanically classified as fruit, because they are seed-bearing structures that develop from the ripened ovaries of flowers, tomatoes are generally considered vegetables in Mexico as well as other countries. (In 1893, the U.S. Supreme court declared the tomato a vegetable based on the fact that it was generally eaten as part of the main course rather than dessert, and therefore was subject to a tariff law that imposed a duty on vegetables.) In fact, botanically speaking, the tomato is more specifically a berry, since the entire fruit wall is fleshy.

Unlike the tomatillo, which did not get too far from Mexico until recent years, the tomato was brought to Europe and did well in the Mediterranean climate, although it was some time before it was accepted as part of the European culinary repertoire. A recipe for spaghetti with tomato sauce did not appear in Italy until 1837, and in Europe and the United States tomatoes were looked upon with suspicion, possibly because of being a member of the nightshade family.

Although such forward thinkers as Thomas Jefferson, who grew tomatoes in the 1780s, scorned the ignorance of tomatoes’ nutritional value, it was not until the late nineteenth century that tomatoes made their way into the American diet. However, once in the mainstream, they gained a permanent place on the menu and today the tomato is the subject of more genetic studies than any other New World plant except corn.

Today, tomatillos have joined tomatoes in the produce departments of supermarkets in several countries, although the sight of fresh husk tomatoes ranging in color from pale yellow to green to deep purple is particularly beautiful in the markets of Central Mexico. And like true tomatoes, husk tomatoes are available canned in countries where they are not sold fresh. This might be an alternative to not using them at all, but the flavor and consistency change dramatically when they are canned, taking on a mushy consistency and tinny flavor. The canned version cannot be substituted for the fresh in raw salsas, although it can be used in cooked sauces. The same goes for the true tomato, which, although it takes better to canning, cannot be used in fresh salsas.

Because of the widespread use of salsas, tomatoes and tomatillos appear in one form or another at just about every meal in Mexico. At breakfast, or the larger almuerzo (brunch) they appear in either red or green sauce for chilaquiles, or both red and green for huevos divorciados, or green sauce for huevos al albañil. At the midday main meal they are liable to show up in one of several hundred regional guisados, or stews, as well as soups and salads. And for the late supper, people are likely to enjoy tacos with salsa, tortas with fresh sliced tomatoes, or any of a number of corn-based street foods, all served with salsa.

The depth of flavor of many Mexican salsas is achieved by roasting the ingredients. Tomatoes, onions, chiles and garlic all benefit from this process, which is done on a comal, although a dry pan or griddle may be used. When a recipe calls for roasting garlic, the peels are left on until after the garlic is charred on the outside.

When it comes to salsas, think outside the box. Any of the following salsas, in addition to being used as condiments, can fulfill other culinary roles. Add leftover fresh salsas to beaten eggs as they are being scrambled, or to sandwich fillings or cracker spreads. Add cooked salsas to soups, stews and beans or serve them with sautéed or grilled chicken or meat, or even with pasta. Green salsas are particularly nice with fish, and all of them go beautifully with eggs. Offer two or three salsas at your next barbeque or picnic, and guests will come up with their own ways to use them.