Why is a tomato a fruit

Solanum lycopersicum (or formerly, Lycopersicon esculentum) is a perennial plant in the nightshade genus (Solanaceae), usually multi-branched, spreading as far as six feet and is most frequently recumbent, however some forms of tomato plant are smaller and remain upright. Its leaves are usually hirsute, compound and feather-shaped, frequently odorous and can grow up to 18 inches in length. The plant flowers are yellow, hanging and clustered, with five pointed lobes.
After the tomato plant comes in to flower, it bears a fruit which although first green, is usually red, but sometimes yellow when ripened. The fruit can range in size from a diameter of about half an inch to 3-4 inches, and are mostly spherical, though fruit from some forms of the plant offer up a smaller, elongated fruit. The fruit is a soft fleshy succulent berry. Internally, two or more cells of seeds are housed in a gelatinous pulp. The fruit is a known source of vitamin C (about 20-25% RDA per 100g), which is concentrated mostly in the pulp.

The confusion surrounding the tomatoes designation as a fruit is most likely a product of the way in which we commonly use it. Much of the culinary use of tomatoes usually places them raw alongside vegetables, for example, in salads and sandwiches or in pickles, and so the natural inclination is to consider it another vegetable. However, in a strict botanical sense, a fruit is defines as the fleshy or ripened ovary of a plant that encloses either a single, or many seeds. This definition means that several types of food commonly thought to be vegetables and even nuts are, in fact, fruits; corn, tomatoes, cucumbers and almonds are all technically fruits. It is thought the wild form of the plant originated in the Andes, possibly in Peru and Ecuador. It was domesticated in Mexico before travelling the Atlantic to Europe with Spanish explorers in the 16th century. In northern Europe, the tomato plant was first grown as an ornamental plant. Early botanists recognized its similarities to known poisonous species, Deadly Nightshade and Belladonna. Consequently, it was not readily taken as a food. The roots are indeed rich in the neurotoxin solanine, making them poisonous to humans. It was first used as a food by Italians and Spaniards and remains a popular part of their cuisine.

Europeans were very fond of the tomato and are responsible for introducing some of the language’s common nicknames for the fruit. Italians called the tomato the pomodoro, or ‘golden apple’, perhaps indicating that early imports were of a yellower hue than later generations. The French claim to have found the fruits aphrodisiacal properties and dubbed it the ‘love apple’.

By the 18th century, Europeans had taken the tomato plant to North America, and records indicate Thomas Jefferson was fond of the plant, growing them at Monticello in 1781. Although in the US small local populations began using the tomato as food as early as 1810, it was not until the 20th century that the tomato entered the broader popular cuisine of the United States. Today, the US is second only to China in its production of the fruit, accounting for about 10% of global production.