Sweetness and acidity is also in part a result of whether a tomato variety is meaty or juicy, as well as being influenced by the number of days to maturity. The longer a tomato has to mature on the vine, the higher the sugar content can be. Some beefsteak varieties have long been grown for their meatiness, but some beefsteaks have more seeds and gel than others do. Many pink and yellow tomato varieties are meatier and have fewer seeds and less gel, giving them a milder taste. Plum and pear tomatoes, developed more than a century ago in Italy, have firm flesh with few seeds and gel, and cook down to a thick paste or sauce.
Tomato color depends on varying amounts of carotene pigments in their flesh and skin.
Most tomatoes are high in lycopene, the pigment that makes tomatoes red. Tomatoes also have varying proportions of betacarotene, the yellow-orange pigment found in carrots and other orange vegetables. Red tomatoes can range in color from deep purple, fiery red to pink. And yellow tomatoes range from orange to lemon yellow and even white. Though pigment determines color, no variety is healthier for you than another.