The tomato –Solanum lycopersicum – is a plant native to tropical and subtropical regions.
The fruit is a berry of variable size and shape, red or orange when ripe, with a smooth epicarp (skin), fleshy mesocarp and endocarp divided into lodges (or loculi), filled with thick juice and containing numerous flattened, yellowish-white seeds enveloped in a gelatinous membrane. Each plant produces 10,000 to 15,000 seeds.
The size of the vegetable and its processing determine more or less important variations in nutritional values.
The tomato contains very few carbohydrates. Much of the mass of the tomato is composed of water. It contains potassium, magnesium and phosphorus. Abundant in vitamin C, good content of vitamin A and K, fair supply of B vitamins and folate. Absent vitamin B12.
The caloric intake is modest, 19 kcal per 100 grams.
The ripe tomato has a high content of glutamic acid, which gives the apple its characteristic umami taste, hence the excellent result in combining tomatoes with protein-rich foods (meat).
Like all solanaceous plants, tomatoes contain several toxic substances, alkaloids that in the plant have a defense function against pests. The best known is solanine, which acts as a repellent for insects, worms, insecticides, fungicides and bactericides. Centuries of selection have ensured that this substance is decidedly low.
Another alkaloid found in tomatoes is tomatine, which is found in the leaves and stems, as well as in the fruit. There are no data on toxicity in humans. In animals the symptoms of intoxication are similar to those caused by solanine, that is vomiting, diarrhea, abdominal pain. The content of this substance decreases as the tomato matures.
The tomato is rich in lycopene, which is the substance that gives it its bright red color. Lycopene is a powerful antioxidant that can inactivate free radicals.
Lycopene is ten times more effective than vitamin E. Scientific studies have demonstrated a beneficial protective effect against certain forms of cancer such as prostate, lung and stomach.
Lycopene also has protective effects against cardiovascular disease.
In processing, chopping and shredding promote the release of lycopene, and cooking significantly increases its absorption.