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| Source: http://davesgarden.com/members/Lilith/ | Source: http://plantsdatabase.com/showpicture/3405/ |
Last updated: 15th January 2003
| CARAWAY |
Family: Umbelliferae
Genus: Carum
Species: carvi
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| Source: http://davesgarden.com/members/Lilith/ | Source: http://plantsdatabase.com/showpicture/3405/ |
Contents
General Background
Details of Quality Characteristics
Current Production and Yields
Constraints upon Production
Markets and Market Potential
Other Information
Research
Useful Websites
BioMat Net
Contacts
References
General Background
Names: Fr.: Carvi; It.: Carvi; Sp.: Alcaravea;
Ger.: Kummel; Dtch.: Karwij; Dan.: Kommen;
Gr.: Karos; Russ.: Tmin; Yug.: Kumina
Caraway is normally a biennial much-branched
herb, 30 - 80cm in height, with narrow finely
grooved leafy stems. It produces a deep taproot
and a rosette of dark green, finely cut,
feathery leaves in the establishment year.
It has a high vernalisation requirement to
initiate the production of flowering stems
in the second year, which grow to a height
of up to 75cm. The flowers are produced on
umbels, are white and 2-3 mm across, the
outer ones larger than the inner ones. They
open from late April onwards and are succeeded
by fruits which are 3-6 mm long, and light
brown, ripening from early July.
Caraway is native to the Mediterranean regions
of Europe, Asia and North Africa. It only
occurs as a naturalised species in northern
Europe. Caraway is an ancient cultivated
species known for its characteristic aromatic
small dry fruits (seeds). The seeds are used
for spicing bakery products, cooked meats,
salads, pickles and drinks. The flavour of
caraway is derived from the essential oil.
The essential oil is also valued pharmacologically,
used in perfumery and has some anti-bacterial
properties.
Details of Quality Characteristics
The caraway fruit contains two main essential
oils, carvone (50-60%) and limonene (35-45%).
The oil is secreted in ducts located in the
pericarp of the fruit. The essential oil
content may vary between 2 and 7% of the
air dried fruit weight (Toxopeus and Bouwmeester
1993). Seed content of carvone varies between
1.3% and 3.5%. Caraway grown in more northerly
latitudes is generally richer in essential
oil than that grown in more southern regions.
Where grown in full sun a greater percentage
and richer oil is obtained.
Current Production and Yields
Caraway is cultivated in the Netherlands,
Finland, Hungary, Morocco, Iran, India and
Russia (Toxopens and Bowmeester 1993, Halua
et al 1986, Hornok 1985). It has been grown as
a field crop in Holland for over 200 years,
here they cultivate the main crop, producing
and exporting far larger quantities than
any other country. The area has fluctuated
between 10 and 10,000 ha annually but recently
has declined to 150 ha due to low prices
(Toxopeus and Bouwmeester, 1993). The crop
in the Netherlands is grown as a spring biennial.
Annual forms have been identified of Polish,
Hungarian and Egyptian types, this has enabled
the production of a stable annual type, which
is registered as the cultivar Karzo (Poyopeus
and Bouwmeester, 1993). During the 1990’s
there was a scarcity of Caraway, owing partly
to the fact that the extensive area of land
in Holland usually used for cultivation of
the plant was devastated by floods.
| Seed Yield (t/ha) | Carvone % | |
| Netherlands biennial (1993) | 2.3-3.0 | 1.65-2.5 |
| Netherlands annual (1993) | 1.2-1.7 | 1.3-1.7 |
| Finland | 3.2 | 2.1-3.5 |
| Hungary | 1.3-1.8 | - |
| UK (1991/92) | 1.6-1.9 | - |
The most recently produced biennial cultivars
from the Netherlands produce harvested yields
of about 2.5 t/ha with a carvone content
of about 2%. The newer annual types have
a lower yield potential, around 1.5 t/ha
and carvone content of about 1%.
Constraints upon Production
The species can be grown successfully in
the cool wet climate of western Europe and
in the drier and warmer climates of central
Europe and the Middle East. The carvone content
of caraway seed is said to be higher when
the crop is grown under moist conditions.
However, high rainfall during flowering adversely
affects yield as do drought conditions during
crop maturity. There is some evidence that
a high rate of photosynthesis during fruit
maturity tends to increase essential oil
content while strong wind at maturity can
reduce the essential oil content by volatilisation
(Toxopeus & Bouwmeester, 1993).
Traditional types suffer from a high degree
of seed shatter, but low shatter varieties
are now available. Seeds will rampantly self-sow
if shattering occurs so it is important to
minimise the risk of this occurring.
Markets and Market Potential
The estimated world production of caraway
oil is £200,000. (Verlet, 1993)
Traditionally caraway is cultivated for the
fruits, used as a flavouring and spice. It
is particularly associated with central European
countries where it is used to flavour bread,
biscuits and cheese. It is also the basic
flavour for the liqueur Kummel.
The young leaves may be used in salads and
the thick tap-root eaten as a vegetable,
similar to yet much smaller than parsnip.
S-Carvone is a common constituent in food
and perfumery products. It can have anti-fungal
activity as well as suppressing sprouting
in potatoes (Oosterhaven et al, 1992; Storey, 1993).
In the UK alone, some 304 million tonnes
of potatoes are held in store annually, awaiting
sale or processing. Most of these require
repeated treatments with a sprouting suppressant,
usually clorpropham or tecnazene. In the
UK it is estimated that some 135 tonnes of
the suppressant were used in 1994 and 130
tonnes in 1990 (MAFF Pesticide Usage Survey
141). Some concern, not yet resolved, has
been expressed over the safety of these two
chemicals. Carvone however, has GRAS (Generally
Regarded as Safe) status in the USA. Luxan
UK is the company which will develop carvone
in the UK.
It was thought possible that carvone could
also be used to replace maleic hydroxide
for sprouting suppression of onions. Maleic
hydroxide has had bad publicity and much
research has been done to replace it (Hiron,
1993; Lancaster, 1992). However, carvone
is applied to potatoes in storage whereas
maleic hydrazide is applied to onions in
the field. It is not thought acceptable to
introduce a post-harvest ‘chemical’ treatment
to replace the current pre-harvest treatment
in onions.
Caraway contains 7,860 to 30,180 ppm limonene
in the seed. Limonene is said to lower cholesterol,
and one study has suggested that limonene
can dissolve gallstones. (Duke and du Celier,
1993). Caraway oils are also thought to calm
nerves and soothe mental fatigue. It is known
to settle the stomach, nervous digestion,
colic, flatulence and gastric spasms. As
an expectorant it helps clear bronchitis,
bronchial asthma and coughs. It is also helpful
in cases of sore throats and laryngitis.
The oil can also help to flush toxins out
of the urinary tracts. It is said to increase
milk in nursing mothers, relieve period pains
and relieve itching skin and acne.
Other Information
Caraway can be grown on a variety of soils,
although it thrives on fertile, water-retentive
soils, it also benefits from deep cultivation.
The plant prefers a position in full sun
yet protection from excessive heat and humidity.
The seed may be sown in autumn or during
March / early April at a rate of 9 kg/ha
in drills 30 cm apart. As caraway is a biennial
it is often sown with a cover crop (often
dill or coriander) which matures in the first
season. The plants flower in May of the second
year, and the seeds ripen from early July.
Annual types flower from July and fruits
ripen during September. The crop responds
well to dressings of up to 75kg/ha each of
nitrogen, phosphate and potash.
Weed control is important - linuron products
are safe, but not approved for use in all
countries. Losses from seed-shedding can
be minimised by windrowing plants as the
first fruits ripen then combining when ready.
The yield of seed averages 1.25t/ha, but
may vary from 0.75-2.0t/ha or more (ADAS,
1980). Annual types are harvested in late
September and may be direct combined as losses
due to seed shed are usually lower. The essential
oil content of Dutch caraway seed ranges
from 3-7%, averaging 4% (Guenther, 1949).
In the USA a yield of 0.9-1.35t/ha may be
expected under favourable conditions, however
this does not represent an annual yield because
the crop is sown in the early spring and
does not yield a crop until the second June.
Research
During the last few years the Netherlands
have concentrated research on the development
of a caraway crop for industrial purposes.
This has included work on agronomy and plant
breeding, investigations into other potential
uses of carvone and the testing of carvone
in potato stores as a sprout-suppressing
agent. The latter product mentioned here
is now available commercially.
Useful Websites
http://www.essentialoils.co.za/essential_oils/caraway.htm - Caraway essential oil in aromatherapy
http://www.botanical.com/botanical/mgmh/c/carawa20.html
- General detailed information on caraway
production and uses
BioMat Net
Caraway (Carum carvi)
FAIR-0722 - Production, Processing and Practical
Application of Natural Antifungal Crop Protectants
FAIR-1781 - Terpenes as Natural Chiral Starting
Materials For the Synthesis of Flavours Fragrances,
Pharmaceuticals and Biocontrol Agents
Crops for Flavours/Fragrances
Crops for Pharmaceuticals/Cosmetics
Crops for Fine Chemicals
Contacts
References
