Basil (Ocimum basilicum L.)

Note

Indian names for the so-called sacred basil are marked with an asterisk in the list above. This cultivar (Ocimum sanctum) is characterized by an intensive sweet-camphoric fragrance; in India, it is both used for religious (dedicated to Vishnu) and culinary purposes.

Used plant part

Leaves; frequently, the entire herb (all superterranean parts) is harvested. Best harvesting season is before flowering. The seeds of basil have some use as thickening agent in Thailand, but do not share the leaves' fragrance.

Plant family

Lamiaceae (mint family).

Sensoric quality

Fresh basil leaves have a strong and characteristic aroma, not comparable to any other spice, although there is a hint of cloves traceable.

In addition to the "Mediterranean type" most common in the West, there is a plethora of other varieties or cultivars with different flavour, many of which are hybrids. India has its "Sacred Basil" (O. sanctum = O. tenuifolium) with intensive, somewhat pungent smell; in Thailand, there is another sweet basil with a great licorice aroma (see also cicely). Varieties sold to gardeners in the West include cinnamon basil, campher basil, anis basil and spice basil; the latter has a very pleasant, complex and warm flavour.

A last group of cultivars is characterized by citrus odour: Thai lemon basil (O. citriodorum) has a distinct balm-like flavour, and then there are lime basil and another lemon basil (O. americanum) which has an extraordinarily pure and fresh lemon aroma (see also lemon myrtle on lemon fragrance in general).

Perennial basil species from Africa (Ocimum kilimandscharicum) and Asia (Ocimum canum) have recently been introduced to the European herb and gardening market. These species has a strong, but less pleasant flavour; hybrids between them and Mediterranean basil are a recent innovation, with novel appearance and flavour, and enjoy growing popularity.

All basil varieties have in common that dried leaves are much less aromatic than fresh ones; deep-freezing the herb is the best method of preservation.

In English language, the common basil grown in Italy and other Mediterranean countries is often termed "sweet basil"; this is, though, misleading, because Thai basil has much more of a sweet quality. Thus, I will avoid this term and speak of "Mediterranean type" and "Thai type" instead.
 

Main constituents

The essential oil (less than 1%) is of complex and variable composition. Within the species, several different chemical races exist, and furthermore climate, soil and time of harvest influence not only the amount but also the composition of the essential oil. The most important aroma components are 1,8 cineol, linalool, methyl chavicol (estragol) and, to a lesser degree, eugenol. Further monoterpenes (ocimene, geraniol, camphor), sesquiterpenes (bisabolene, caryophyllene) and phenylpropanoids (methyl cinnamate, methyl eugenol) are present in varying amounts and strongly influence the flavour.

The quality traded in Europe, Western Asia and North America (Mediterranean type) is characterized by 1,8 cineol and linalool, plus smaller amounts of estragol and eugenoles. This description holds also for both green-leaved and red-leaved (anthocyanine containing) strains.

Indian "Sacred Basil" (O. sanctum = O. tenuifolium) owes its stronger, somewhat pungent taste to a sesquiterpenoid, beta-caryophyllen, and a phenylpropanoid, methyl eugenol. Chemotypes centering on eugenol are rare; their odour resembles cloves closely (O. gratissimum).

A couple of chemotypes are dominated by methyl chavicol (estragol); these stand apart by their sweet anis or licorice fragrance (anise basil, sweet Thai basil). Lemon-scented varieties contain mostly citral. The African species, O. kilimandscharicum, is characterized by much camphor besides 1,8 cineol; camphor is also found, albeit in lesser quantities, in kilimandscharicum hybrides with O. basilicum. Cinnamon basil owes its scent to a chemical also found in cinnamon, methyl cinnamate. Last, a very pleasantly scented cultivar called "spice basil" was found to contain beta-bisabolen, 1,8 cineol und estragol.

This collection demonstrated clearly that basil has a remarkably variable secondary metabolism, as is often found in the mint family: Perilla and mints show a similar genetic diversity. For several related herbs like thyme, oregano and sage the composition of the essential oil is known to depend on climate, soil, genetic strain and season.

The dark red foliage of some basil varieties is caused by pigments of anthocyanine type, which are commonly found in reddish leaves. Some basil varieties contain up to 200 ppm anthocyanines in their leaves (see annatto about vegetable colourants).

Origin

Genus Ocimum is widespread over Asia, Africa and Central and Southern America; it appears to have its center of diversity in Africa. Basis was probably first put to cultivation in India.

Today, basil is cultivated in many Asian and Mediterranean countries; main exporters (for the European market) are France, Italy, Morocco and Egypt. There is also significant basil production in California.
 

Etymology

The name basil and its cognates in all European tongues are derived from Greek basileús "king", because of the royal fragrance of this herb (cf. French herbe royale).
The Greek word means essentially "people's leader": baínein "go" and laós "people". The first element is indeed cognate to both English come and Latin venire (Indo-European root GWEM-), the second has no cognates in Modern English, for Old English leod has been abandoned in favour of Romance "people"; related are German Leute, Old French liode, Lithuanian liaudis "people" and Latin liber "free man" (Indo-European root LEUDH- "grow upwards").

A similar association is found in the Quenya name (aran "king").

The genus name Ocimum is a latinized derivation of the Greek verb ózein "smell" (cf. ozone "the smelling one" and English odour).
 

Mediterranean Basil is one of the most pleasant spices, and indispensable for several Mediterranean cuisines. The sweet and aromatic fragrance is especially popular in Italy. Since the delicate aroma of basil is quickly destroyed by cooking, chopped basil leaves are frequently sprinkled over cold or warm dishes before serving. A famous recipe often found outside of Italy is insalata caprese (Capri sald): Tomato slices topped with creamy mozarella cheese and basil leaves, seasoned with aceto balsamico (balsam vinegar) and highest quality olive oil.

The famous pesto is a speciality of Liguria, a region in North Western Italy. This paste is made from fresh basil leaves together with extra vergine olive oil, pine nuts, the famous Italian cheese called parmigiano and garlic; it is served with Italian noodles (pasta). Besides tasting excellent, pesto is also efficient in conserving basil, even without deep-freezer (although it does keep better frozen).

The recipe for pesto can be generalized to other herbs; for example, pesto made from bear's garlic tastes great and also solves the problem of conserving this spice. Very extravagant pesti can be prepared from chervil or lemon balm. Frankfurt Green Sauce is an example of a similar sauce employing a mixture of seven herbs (see borage).

In Italian cuisine, basil is frequently combined with tomatoes, e.g. together with pickled olives, capers and garlic for tasty tomato sauces. Salads made only from tomatoes, extra vergine olive oil, red wine vinegar (see dill about herbal vinegars) and basil are simple but delicious. Basil is, though, less used for meat dishes; Italian cooks prefer oregano for this purpose.

Fresh basil may also form part of bouquet garni (see parsley), mostly in Italy.

Similar use is made of basil in the Far East; it is especially popular in Vietnam and Thailand. Every visitor to Bangkok who dared to try local cuisine will probably never forget the phantastic basil aroma that emanates from nearly every pot at the numerous foodstalls. The basic ideas of Thai cookery are revealed in gai pad bai krapow, chicken with chiles and basil: Despite a searing and truly hellish hotness, the dish provides heavenly pleasures by its fine basil odour.

When using basil in South East Asian recipes, one should consider that the basil varieties grown there have a much different taste than the Mediterranean herb predominantly available in the West; true Thai basil (bai horapha) is, though, available in Thai food stores. See coconut for a discussion of
Thai curries.