August is prime tomato season in many parts of the United States. To me, a tomato is defined by its texture. Flavor, moisture, acidity, and ripeness are all important but all these factors are meaningless if you have a tomato that is soft and mushy. What makes a tomato mushy and soft is temperature — if at any point a tomato is cooled below 45 degrees for an extended period of time, its cell structure will collapse. You should never refrigerate tomatoes at home for this reason. The further a tomato has to travel, the greater the chance it will be exposed to refrigeration so the best tomato to buy is a local one.
The Large Round is the most commonly available tomato and includes several types:
Gassed green: a large round field grown tomatoes that is harvested a firm green (so it can be transported with less damage) and treated with Ethylene gas to ripen (just like bananas). This is the type of tomato commonly used in fast food or in any operation that requires a steady stream of ripe fruit on a regular basis. This is also the least flavorful and we tend to avoid selling them.
Field ripened: this is a large round that is allowed to ripen in the field.
Green (hot) house beefsteak: this is a green house grown version that tends to be more expensive but available over a longer period of time. This tomato tends to be more consistent in size and condition.
Vine on (or cluster tomato); the most common tomato produced today. Vine ripened, this tomato is harvested and sold with the stems attached. This gives the tomato that characteristic tomato smell you get from fruit grown in a garden.
Roma or Plum tomatoes are almost as common and can be used for both cooking and fresh. These types tend to be smaller than Large Round and are often long and narrow in shape (almost like a football). Most pastes and sauces are made with this variety. The picture is a variety called San Marzano- one of the oldest commercially produced Roma varieties.
Cherry tomatoes are also available year round and are by and large the best bet off season for flavor and texture. The most common variety product commercially is the Grape tomato- an oblong grape shaped red cherry. Cherry tomatoes tend to ripen faster than large round tomatoes so you can start to see local availability earlier in the summer. The local season brings some excellent varieties that do not travel as well as the Grape or common red cherry. Among these are:
Sweet 100: a small red cherry generally 1/3 to 1/2 the size of a common cherry tomato. Intensely sweet and flavorful.
Sun Gold: an extremely prolific but fragile cherry tomato. Small and golden in color, this variety is very popular with backyard gardeners.
Red and yellow pear: larger pear shaped cherry tomatoes that are generally not as sweet as the smaller varieties but hold up well in cooked dishes.
Heirloom tomatoes are by far the hardest to find consistently for the very reasons they are so wonderful when they are available. 95% are field grown; vine-ripened and are only available in the late summer- there is some green house production but it is extremely limited. Heirloom varieties come from all over the world and are very difficult to grow and predict. Growers can often go into a field expecting to harvest 100 cases and come out with 10 (or 1,000). Most varieties are also irregular in shape and size (ranging to a few ounces to several pounds) which requires that they are hand picked and packed. Heirloom fields have produced some really weird specimens:There are hundreds of varieties produced but three varieties make up 85% of the product that comes to market:
Cherokee Purple (Black Krim is a similar variety): This is a purple or very dark red variety that is generally the first variety to appear every season. The Cherokee Purple is a beefsteak variety — this means it is mostly very large and has a firm, fleshy texture (as opposed to soft or watery).
Brandywine: Originating in Russia the Brandywine is the most popular variety of heirloom produced today. Brandywines are large red beefsteaks (there is also a yellow variety) that are extremely sweet and low in acidity in addition having excellent texture. This is the perfect sandwich or salad tomato.
The Marvel Stripe (or Striped German) is hands down the most beautiful tomato produced today. Originating in Mexico this beefsteak variety is yellow with a red interior blush — I like to cut them into inch thick slices and serve them alone (with some shredded basil, oil and balsamic vinegar)