Basil (Ocimum basilicum) is an annual herbaceous plant, belonging to the Lamiaceae family, normally cultivated as an aromatic plant. The name derives from medieval Latin basilicum, with its origin from the Greek basilikon (phyton) (‘royal, majestic plant’), from basileus ‘king’. It grows well when the sun is abundant and the temperature between 20 °C and 25 °C and cannot withstand temperatures below 10 °C. It likes frequent watering, but with well-drained soil, as water stagnation is harmful to the roots. It is grown in vegetable gardens or in pots. The flowering period is between June and September. Basil plants must be regularly trimmed, removing the vegetative apices and flowers, to allow lush growth and to lengthen the life cycle, which ends with the production of seeds. On stems left to flower, leaf growth slows and stops, the stem becomes woody, and the production of the essential oil that produces the perfume declines. Originally from India, basil is typically used in Italian cuisine and in Asian cuisines, especially in Taiwan, Thailand, Vietnam, Cambodia and Laos, due to the pronounced scent of its leaves, which can be more or less sweet or pungent depending on the variety. Some 60 varieties and cultivars of O. basilicum have been classified, which differ in appearance and aroma.
In cooking, basil should be used fresh and added to dishes at the last moment. Cooking quickly attenuates its flavour to the point of neutralising it, leaving little of its scent behind. When dried, it loses its flavour completely, leaving a faint scent of hay. It can be pounded in a mortar to break up the cells containing the essential oil, releasing its aroma. It can be kept in the refrigerator for a few days, wrapped in a kitchen towel. Frozen leaves, on the other hand, retain their flavour for several months.