Basil

Basil is a tender plant, and is used in cuisines worldwide. Depending on the species and cultivar, the leaves may taste somewhat like anise, with a strong, pungent, often sweet smell.

There are many varieties of basil, as well as several related species or hybrids also called basil. The type used commonly as a flavor is typically called sweet basil (or Genovese basil), as opposed to Thai basil (O. basilicum var. thyrsiflora), lemon basil (O. × citriodorum), and holy basil (Ocimum tenuiflorum). While most common varieties of basil are treated as annuals, some are perennial in warm, tropical climates, including holy basil and a cultivar known as “African blue basil”.

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Phytochemistry
The various basils have such different scents because the herb has a number of different essential oils in different proportions for various cultivars. The essential oil from European basil contains high concentrations of linalool and methyl chavicol (estragole), in a ratio of about 3:1. Other constituents include: 1,8-cineole, eugenol, and myrcene, among others. The clove scent of sweet basil is derived from eugenol. The aroma profile of basil includes 1,8-cineole and methyl eugenol.

Taxonomy
The exact taxonomy of basil is uncertain due to the immense number of cultivars, its ready polymorphy, and frequent cross-pollination (resulting in new hybrids) with other members of the genus Ocimum and within the species. Ocimum basilicum has at least 60 varieties, which further complicates taxonomy.

Most basils are cultivars of sweet basil.

•  Anise basil, Licorice basil or Persian basil (O. basilicum ‘Licorice’)
•  Cinnamon basil (Ocimum basilicum ‘Cinnamon’)
•  Dark opal basil (Ocimum basilicum ‘Dark Opal’)
•  Lettuce leaf basil (Ocimum basilicum ‘Crispum’)
•  Purple basil (Ocimum basilicum ‘Purpurescens’)
•  Rubin basil (Ocimum basilicum ‘Rubin’)
•  Globe basil, dwarf basil, French basil (Ocimum basilicum ‘Minimum'[10])
•  Thai basil (Ocimum basilicum thyrsifolium)

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