Overview
Tomatoes can be classified several ways but usually fall into one of two types: determinate and indeterminate. Determinate varieties grow to a certain height and produce fruit for one cycle. Indeterminate varieties require staking/caging and grow throughout the season. Commercially, determinate varieties are more widely grown than indeterminate; the latter varieties are typically grown in home gardens. Hundreds of varieties exist as either an heirloom or a hybrid. Heirloom seeds can be saved for the next season and are often used for generations. Hybrid tomatoes are a combination of two varieties and because the seeds may produce something different from the parent fruit, the seeds are not usually saved. Tomatoes also have several different shapes: globe, cherry, beefsteak, and imply. The USDA categorizes tomatoes as either greenhouse, fresh, cherry, or on-the-vine.
Health & Nutrition
Tomatoes are high in vitamins A & C and are a good source of potassium. They are naturally fat and cholesterol free, are low in calories and have very low sodium.
U.S. Grades
The USDA Color Stage 5 is described as “Light red: 60% to 90% of the surface is not green; in the aggregate, shows pinkishred or red.” The USDA Color Stage 6 is described as “Red: More than 90% of the surface is not green; in the aggregate, shows red color.”
Storage Conditions
Mature green tomatoes are typically harvested by hand and sorted according to size, graded, and placed in temporary cold storage. Optimum temperatures for mature green tomatoes are 55 to 60ºF (12.5 to 15ºC); for light red (USDA Color Stage 5*), 50 to 55ºF (10 to 12.5ºC); and for firmripe (USDA Color Stage 6*), 44 to 50ºF (7 to 10ºC) for three to five days. Tomatoes held at 50ºF (10ºC) for longer than two weeks or at 41ºF (5ºC) for longer than six to eight days are subject to chilling injury. Optimum relative humidity is 90 to 95% but extended periods of higher humidity may encourage growth of surface molds due to condensation. Ethylene is typically applied to mature green tomatoes for uniform ripening. Because ripening tomatoes produce ethylene at a moderate rate, storage or shipping with ethylene-sensitive commodities should be avoided.
Sizes
Tomatoes vary in size. Typically, roma’s run from small, medium, large, extra large, and jumbo. Additionally, tomatoes can vary from 3×4, 4×4, 4×5, 5×5, 5×6, 6×6, and 6×7. There are other sizes as well, but these are common examples.
