Vitis vinifera

Wild grapes were harvested by neolithic foragers and early farmers. For thousands of years, the fruit has been harvested for both medicinal and nutritional value; its history is intimately entwined with the history of wine.[3]

Changes in pip (seed) shape (narrower in domesticated forms) and distribution point to domestication occurring about 3500–3000 BC, in southwest Asia, South Caucasus (Georgia), or the Western Black Sea shore region (Romania and Bulgaria). The earliest evidence of domesticated grapes has been found at Gadachrili Gora, near the village of Imiri, Marneuli Municipality, in southeastern Georgia; carbon-dating points to the date of about 6000 BC.[4][5][6] Grape pips dating back to the 5th–4th millennium BC were also found in Shulaveri; others dating back to the 4th millennium BC were also found in Khizanaant Gora, all in the country of Georgia.[7]

Cultivation of the domesticated grape spread to other parts of the Old World in pre-historic or early historic times.[5] The first written accounts of grapes and wine can be found in the Epic of Gilgamesh, an ancient Sumerian text from the 3rd millennium BC. There are also numerous hieroglyphic references from ancient Egypt, according to which wine was reserved exclusively for priests, state functionaries and the pharaoh.[8]

Grape harvest on Etruscan terracotta from the 6th century BC

Hesiod in his Works and Days gives detailed descriptions of grape harvests and wine making techniques, and there are also many references in Homer. Greek colonists then introduced these practices in their colonies, especially in southern Italy (Magna Grecia), which was even known as Enotria due to its propitious climate.

The Etruscans improved wine making techniques and developed an export trade even beyond the Mediterranean basin.[9] The ancient Romans further developed the techniques learnt from the Etruscans, as shown by numerous works of literature containing information that is still valid today: De Agri Cultura (around 160 BC) by Cato the Elder, De re rustica by Marcus Terentius Varro, the Georgics by Virgil and De re rustica by Columella. During the 3rd and 4th centuries AD, the long crisis of the Roman Empire generated instability in the countryside which led to a reduction of viticulture in general, which was mainly sustained only close to towns and cities and along coastlines.

Between the 5th and 10th centuries, viticulture was sustained almost exclusively by the different religious orders in monasteries. The Benedictines and others extended the grape growing limit northwards and also planted new vineyards at higher altitudes than was customary before. Apart from 'ecclesiastical' viticulture, there also developed, especially in France, a 'noble' viticulture, practiced by the aristocracy as a symbol of prestige.[10][11] Grape growing was a significant economic activity in the Middle east up to the 7th century, when the expansion of Islam caused it to decline.[12]

Vineyard in Burgundy

Between the Low Middle Ages and the Renaissance, viticulture began to flourish again. Demographic pressure, population concentration in towns and cities, and the increased spending power of artisans and merchants gave rise to increased investment in viticulture, which became economically feasible once more. Much was written during the Renaissance on grape growing and wine production, favouring a more scientific approach. This literature can be considered the origin of modern ampelography.

Grapes followed European colonies around the world, coming to North America around the 17th century, and to Africa, South America and Australia. In North America it formed hybrids with native species from the genus Vitis; some of these were intentional hybrids created to combat phylloxera, an insect pest which affected the European grapevine to a much greater extent than North American ones and in fact managed to devastate European wine production in a matter of years. Later, North American rootstocks became widely used to graft V. vinifera cultivars so as to withstand the presence of phylloxera.[13]

In the second half of the 20th century there was a shift in attitude in viticulture from traditional techniques to the scientific method based on fields such as microbiology, chemistry and ampelography. This change came about also due to changes in economic and cultural aspects and in the way of life and in the consumption habits of wide sectors of the population starting to demand quality products.

In 2007, Vitis vinifera was the fourth angiosperm species whose genome was completely sequenced. These data contributed significantly to understanding the evolution of plants and also how the aromatic characteristics of wine are determined in part by the plant's genes.[14] This work was a collaboration between Italian researchers (Consorzio Interuniversitario Nazionale per la Biologia Molecolare delle Piante, Istituto di Genomica Applicata) and French researchers (Genoscope and Institut National de la Recherche Agronomique).

Also in 2007, scientists from Australia's Commonwealth Scientific and Industrial Research Organisation (CSIRO), working in the Cooperative Research Centre for Viticulture, reported that their "research suggests that extremely rare and independent mutations in two genes [VvMYBA1 and VvMYBA2 of red grapes] produced a single white grapevine that was the parent of almost all of the world's white grape varieties. If only one gene had been mutated, most grapes would still be red and we would not have the more than 3000 white grape cultivars available today."[15][16]

Their flowers, small and greenish to white, are grouped in inflorescences and their fruits, of different shapes depending on the subspecies, are berries grouped in clusters. The calyx is single-leaf with 5 short, deciduous teeth. The corolla consists of five petals, fused at the top and base, and then falls off in its entirety. Opposite the petals there are five stamens interspersed with glands. The upper ovary bears a very short style with a button-shaped stigma. The wild vine is a dioecious plant, the male and female flowers arise on different plants, but the cultivated forms are hermaphroditic, allowing self-pollination.

The fruit is a berry, known as a grape that is ovoid or globular, dark blue or greenish, usually 2-locular with 5 seeds; in the wild species it is 6 mm (0.24 in) diameter and ripens dark purple to blackish with a pale wax bloom; in cultivated plants it is usually much larger, up to 3 cm (1.2 in) long, and can be green, red, or purple (black).

V. vinifera contains many phenolic compounds.[29] Anthocyanins can be found in the skin of the berries, hydroxycinnamic acids in the pulp and condensed tannins of the proanthocyanidins type in the seeds. Stilbenoids can be found in the skin and in wood.

Trans-resveratrol is a phytoalexin produced against the growth of fungal pathogens such as Botrytis cinerea[30] and delta-viniferin is another grapevine phytoalexin produced following fungal infection by Plasmopara viticola.[31]

• Astringin

Vitis vinifera red cultivars are rich in anthocyanins that impart their colour to the berries (generally in the skin). The 5 most basic anthocyanins found in grape are:

• Cyanidin-3-O-glucoside
• Delphinidin-3-O-glucoside
• Malvidin-3-O-glucoside
• Petunidin-3-O-glucoside
• Peonidin-3-O-glucoside

Cultivars like Graciano[32][33] may also contain :

acetylated anthocyanins

• Cyanidin-3-(6-acetyl)-glucoside
• Delphinidin-3-(6-acetyl)-glucoside
• Malvidin-3-(6-acetyl)-glucoside
• Petunidin-3-(6-acetyl)-glucoside
• Peonidin-3-(6-acetyl)-glucoside

coumaroylated anthocyanins

• Cyanidin-3-(6-p-coumaroyl)-glucoside
• Delphinidin-3-(6-p-coumaroyl)-glucoside
• Malvidin-3-(6-p-coumaroyl)-glucoside cis
• Malvidin-3-(6-p-coumaroyl)-glucoside trans
• Petunidin-3-(6-p-coumaroyl)-glucoside
• Peonidin-3-(6-p-coumaroyl)-glucoside

caffeoylated anthocyanins

• Malvidin-3-(6-p-caffeoyl)-glucoside
• Peonidin-3-(6-p-caffeoyl)-glucoside

Isoprenoid monoterpenes are present in grape, above all acyclic linalool, geraniol, nerol, citronellol, homotrienol and monocyclic α-terpineol, mostly occurring as glycosides. Carotenoids accumulate in ripening grape berries. Oxidation of carotenoids produces volatile fragments, C13-norisoprenoids. These are strongly odoriferous compounds, such as β-ionone (aroma of viola), damascenone (aroma of exotic fruits), β-damascone (aroma of rose) and β-ionol (aroma of flowers and fruits). Melatonin, an alkaloid, has been identified in grape.[34] In addition, seeds are rich in unsaturated fatty acids, which helps lowering levels of total cholesterol and LDL cholesterol in the blood.[29]