Foeniculum vulgare Mill.
Family : Umbelliferae
Other names: Common fennel;
sweet fennel; Florence fennel; spigel
Fennel is an erect growing perennial
herb native to southern Europe and the Mediterranean area, commonly
grown for flavoring purposes. The mature seeds are the dried fruits
of this herb which are used commercially, and the young tender shoots
and leaves of the sweet fennel are used in foods in European countries.
This plant has a thickened base of leaves, which can be blanched
or boiled and eaten as a vegetable. Principal fennel production
areas are located in India, the People's Republic of China, Egypt,
Argentina, Indonesia, and Pakistan. Fennel has been known to herbalists
and doctors since time immemorial. It was believed to be the total
cure and have the power to make people young, strong and healthy.
It is one of nine Anglo-Saxon sacred herbs. It was often hung over
doorways to ward off evil spirits. Fennel was used in ancient Greece
and Rome. The name comes from the Latin foenum, a variety
of fragrant hay, reflecting the plant's odour .
Fennel is a greyish-green, strong-smelling
herbaceous perennial, with slim stems, bearing soft lacy, dark green
leaves with thread-like lobes and swollen bases. Creeping rootstock
gradually extends plant into a sparse clump. Reaching a height of
1.5 meters, the plant has small mustard-yellow flowers on a compound
umbel. The fruit splits into two seeds, which are oval in shape
with five ridges. The seed is light green to gray, about 0.75 cm
long, and curved.
The reported life zone of fennel
is 4 to 27 degrees centigrade with an annual precipitation of 0.3
to 2.6 meters and a soil pH of 4.8 to 8.3. Fennel thrives on well
drained loam soil. The seeds should be planted early in spring to
a depth of half an inch and at the rate of a dozen seeds to the
foot and the plants thinned to 4 to 6 inches apart in the row. Only
light cultivation for weed control is necessary. Ordinarily the
plants do not flower the first season, but a full crop of seed will
be produced for several seasons thereafter.
Although a perennial, fennel is generally
grown as an annual or biennial crop. Yields of the dried fruit,
commonly thought of as fennel seed, are low in the first year but
increase in the second. The seeds mature in the fall of the second
season. When the fruiting umbels turn brown they are ready for harvest
and should be cut promptly to prevent shattering. The umbels do
not mature uniformly, and several harvests are therefore necessary
to maximize yield. Mechanical harvesting of commercial stands must
be carefully timed to obtain high yields. The tops containing the
seeds may be spread on fine screens or on a clean wooden floor to
dry. When drying is completed they should be separated from the
stems, cleaned, and stored in bags. The leaves lose most of their
sweet aromatic flavor on drying. Approximately 60 percent of the
essential oil is located in the fruit, with the rest in the rays
of the umber and other green plant parts.
Aroma and flavour
Fennel contains 1 - 3% of a volatile
oil which is composed of about 50 - 60% anethole and about 20% d-fenchone.
Other compunds present in fennel are d-a-pinene, d-a-phellandrene,
dipentene, methyl chavicol, feniculun, anisaldehyde, and anisic
acid. Oil of fennel is commonly available. An oleoresin is also
available with a volatile oil content of only about 3 -6%. Bitter
fennel oil is thought to contain more fenchone (a bitter mixture
with a camphor-like odor and flavor) and less anethole than sweet
fennel oil. Sweet fennel oil is of a superior quality with a more
pleasing aroma and flavour. Some analyses have indicated a lack
of fenchone in sweet fennel and high concentrations of limonene
in bitter fennel.
Both the seeds and the oil distilled
from them are used for flavoring. Fennel seed is used in the food
and flavour industry for addition to meats, vegetable products,
fish sauces, soups, salad dressings, stews, breads, pastries, teas,
and alcoholic beverages. Crushed seed are used in salad dressings,
in mayonnaise, in savoury and sweet baking and as a substitute for
juniper in flavoring gin. Ground fennel is used in many curry powders.
The essential oil and the oleoresin of fennel are used in condiments,
soaps, creams, perfumes, and liqueurs. Several types of fennel differing
in morphology and leaf color are available for ornamental use and
as a fresh vegetable. Soft growing tips are widely used to flavour
and garnish fish dishes, soups and baked foods.
Medicinal and other use
As a medicinal plant, fennel seed
has been used as an antispasmodic, carminative, diuretic, expectorant,
laxative, stimulant, and stomachic. Roots once boiled as a vegetable,
and used as an expectorant in cough mixtures. Fennel has also been
used to stimulate lactation, as a remedy against colic, and to improve
the taste of other medicines. Chinese herbal medicine includes the
use of fennel for gastroenteritis, hernia, indigestion, abdominal
pain, and to resolve phlegm and stimulate milk production. Fennel
is known to provoke both photodermatitis and contact dermatitis
in humans. The volatile oil may cause nausea, vomiting, seizures,
and pulmonary edema. The essential oil has been reported to stimulate
liver regeneration in rats. It has antibacterial properties.