RESUMEN
Composición química de semillas de zanahoria
(Daucus carota L.) cultivadas en Turquía: caracterización
del aceite de semilla y del aceite esencial.
Se determinó la composición química y las propiedades
físicas de las semillas de zanahoria (Daucus carota L.) obtenidas
en Konya, Turquía, con objeto de investigar usos potenciales
de las mismas. Se determinó la humedad, el peso,
el contenido proteico, en aceite, en fibra, en ceniza, en ceniza
insoluble en ácido clorhídrico, los carbohidratos totales, y
el rendimiento de la obtención de aceite esencial a partir de
1000 semillas maduras. Asimismo se determinó la densidad
relativa, el índice de refracción, el contenido en ácidos grasos
libres, el índice de peróxidos, el índice de yodo, el índice
de saponificación y el insaponificable del aceite de la semilla.
Los principales ácidos grasos determinados por
cromatografía gaseosa fueron petroselénico (59.35%), linoleico
(11.82%), palmítico (10.01%), y esteárico (2.41%). El
contenido mineral (Al, Ca, Cu, Fe, K, Li, Mg, Mn, Na, Ni, P,
Se, Sr, V and Zn) de la semillas fue determinado por espectroscopia
de emisión de atómica (ICP-AES). Las semillas resultaron
ser ricas en proteína, fibra y ceniza. Las composiciones
del aceite esencial y del aceite comestible fueron
determinadas por GC y GC-MS. Los rendimientos de aceite
esencial y comestible fueron 0.83 y 7.84%, respectivamente.
Los constituyentes mayoritarios del aceites esencial fueron
carotol (66.78%), dauceno (8.74%), (Z,Z)-α-farneseno
(5.86%), germacreno D (2.34%), trans-α-bergamoteno
(2.41%), y β-selineno (2.20%). Por su parte, carotol
(30.55%), ducol (12.60%) y capaenol (0.62%) fueron los
componentes principales del aceite comestible.
PALABRAS-CLAVE: Aceite esencial – Apiaceae – Composición
– Ducus carota L. – Minerales – Semilla de zanahoria.
SUMMARY
Chemical composition of carrot seeds (Daucus
carota L.) cultivated in Turkey: characterization of the
seed oil and essential oil.
Chemical composition and physical properties were
established in carrot (Daucus carota L.) seeds from Konya,
Turkey to investigate their potential uses. Mature seeds were
evaluated for moisture, crude protein, crude oil, crude fiber,
ash, HCl-insoluble ash, total carbohydrate, essential oil yield
and weight of 1000 seeds. Also, relative density, refractive
index, free fatty acids, peroxide value, iodine value,
saponification number and unsaponifiable matter were
determined in the seed oil. The main fatty acids identified by
Chemical composition of carrot seeds (Daucus carota L.) cultivated in Turkey:
characterization of the seed oil and essential oil
By Mehmet Musa Özcan1* and Jean Claude Chalchat2
1* Department of Food Engineering, Faculty of Agriculture, Selçuk University, 42031 Konya,Turkey.
e-mail: mozcan@selcuk.edu.tr
2 Universite Blaise Pascal de Clermont, Laboratoire de Chimie des Huiles Essentielle,
63177 Aubiere Cedex, France.
gas chromatography were petroselinic (59.35%), linoleic
(11,82%), palmitic (10.01%) and stearic (2.41%) acids.
Mineral contents (Al, Ca, Cu, Fe, K, Li, Mg, Mn, Na, Ni, P, Se,
Sr, V and Zn) of seeds were also determined by Inductively
Coupled Plasma Atomic Emission Spectrometry (ICP-AES).
The seeds were found to be rich in protein, fiber and ash.
The essential oil and edible oil compositions of carrot
seeds from Konya were investigated by GC and GC-MS. The
oil yields of essential and edible oil from carrot seeds were
established as 0.83% and 7.84%, respectively. The major
constituents of seed essential oil were carotol (66.78%),
daucene (8.74)%, (Z,Z)-α-farnesene (5.86%), germacrene D
(2.34%), trans-α-bergamotene (2.41%) and β-selinene
(2.20%). Whereas, carotol (30.55%), daucol (12.60%) and
copaenol (0.62%) were the important components of edible
carrot seed oil. However, the dominant component of both
oils was carotol.
KEY-WORDS: Apiaceae – Carrot seed – Composition –
Daucus carota L – Essential oil – Minerals.
1. INTRODUCTION
Carrot (D. carota L., Apiaceae) is one of the most
commonly used vegetables for human nutrition.
D.carota is called as “havuç tohumu”, “yere geçen”,
“kes, ür” and “pörçüklü” in Turkish. It is a tall robust
biennial spiny-fruited herb growing in dried-out fields
or meadows. Carrots are cultivated worldwide. They
are characterized by relatively moderate
requirements for climate and soil. Owing to their
modest needs for cultivation and storage, they can
be sold fresh throughout the year (Baytop, 1984;
Vogel, 1996; Fritz and Stolz, 1989; Schaller and
Schnitzler, 2000; Schieber et al., 2001). Their juices
and blends are among the most popular nonalcoholic
beverages. A steady increase in carrot
juice consumption has also been reported from
other countries. It is regarded as a healthy food item
because of its high vitamin and fiber content
(Nilsson, 1987; Chen and Tang, 1998; Negi and Roy,
2000; Schieber et al., 2001; Gonny et al., 2004).
In the development of new oil seed crops interest
has turned to the members of the Umbelliferae
family. The yields per hectare (4-30 dt/ha) and oil
content of these oil crops (8-24%) are not extremely
high. But these agricultural crops, which contain
spice plants like caraway, celery, coriander, dill and
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GRASAS Y ACEITES, 58 (4),
OCTUBRE-DICIEMBRE, 359-365, 2007,
ISSN: 0017-3495
parsley, are of interest due to their high amounts of
petroselinic acid (Kleiman and Spencer,1982; Rühl,
1993; Hondelman, 1985; Schuster, 1992; Reiter et
al., 1998a). Carrot seed essential oil is widely used
for its numerous applications concerring the
formulation of certain alcoholic liguors as well as
aromatic and fragrance compositions. It contains
about 0.5-1.6% (v/w) essential oil. Its essential oil is
used for medicinal purposes such as diuretic,
stomachic (Baytop, 1984; Bauer et al., 1990;
Lawrance 1992-1994; Mazzoni et al., 1999). The
high intensity of harsh carrot-like flavor in fresh plant
products is commonly considered to be genetically
determined and has therefore been reduced by
breeding in carrots. Nevertheless, unacceptable
flavor can occur at the consumer level and this is
connected with suboptimal postharvest storage
conditions and harsh handling during distribution. In
carrots, bitter and harsh as well as flat, insipid flavors
have been described in response to ethylene
exposure, mechanical stress or storage in low
oxygen atmospheres (Simon, 1985; Lafuente et al.,
1989; Seljasen et al., 2001; Seljasen et al., 2004).
Various attempts were made at utilizing carrot
pomace in food such as bread (Ohsawa et al., 1994),
cake, dressing and pickles (Ohsawa et al., 1995),
and for the production of functional drinks (Henn and
Kunz, 1996; Schieber et al., 2001). Several studies
on the chemical characterization of carrot seed and
seed oil have been caried out (Mazzani et al.,1999;
Gonny et al., 2004; Zlatanow, 1994; Seljasen et al.,
2004; Lie Ken Jie et al., 1996; Ochocka and
Lamparczyk, 1993; Parker et al., 2003).
Recently, one oil distilled from the blooming
umbels of D.corota L. ssp. carota growing wild in
Poland was characterized by a high content of
monoterpene hydrocarbons (84%), and the major
components were α-pinene (41%) and sabinene
(18%) (Staniszewska and Kula, 2001). No detailed
study on the physical properties, chemical
composition, essential oil composition and mineral
contents of the seeds of D. carota has been
performed so far. The aim of this study was to
establish physical and chemical properties of carrot
seed and oil and chemical composition of essential
and edible oil of the seed oil.
2. MATERIAL AND METHODS
2.1. Material
Carrot seeds were purchased locally from herbal
and vegetable suppliers in Konya in Turkey in the
year 2004. Carrot seeds were transported to the
laboratory in glass jars and held at room
temperature. They were cleaned in an air screen
cleaner to remove all foreign matter such as dust,
dirt, stones and chaff, and immature and broken
seeds were discarded as well. Their moisture
content was measured on arrival. Seeds were dried
to a constant weight at room temperature for
analyses. Prior to a chemical analysis, samples
(about 300 g) were ground to pass a 0.5 mm
screen. Methyl esters of fatty acids (palmitic,
palmitoleic, stearic, oleic, linoleic, petroselinic,
arachidic, vaccenic) were purchased from Sigma
Company. The solvents were used in p.a.quality.
2.2. Oil extraction
The oil was extracted from crushed seeds with
petroleum ether (50 oC) in a Soxhlet extractor. The
extract was evaporated in a vacuum. The lipid
extract was collected in a flask. The extracted lipid
was weighed to determine the oil content and
stored under nitrogen at 4 oC for further analysis.
2.3. Recovery of essential oil
Dried carrot seeds were ground into small
pieces and subjected to hydrodistillation for 4 h
using a Clevenger-type apparatus (Clevenger,
1928), and the oils obtained were dried over
anhydrous sodium sulfate. Essential oil yield on a
dry weight basis was 0.83%.
2.4. Physicochemical properties of seed
and oil
The weight of 1000 seeds was determined. The
chemical and physical properties (moisture, crude
protein, crude oil, crude fiber, crude energy, ash,
HCl-insoluble ash, relative density, refractive index,
free fatty acids, peroxide value, saponification
number and unsaponifiable matter) were analyzed
according to AOAC (1984, 1990). The total amount
of carbohydrate was found by subtracting the
amount of ash protein and fat from total dry matter
(Çag˘ larırmak, 2003).
2.5. Determination of fatty acids
Fatty acids were derived using the boron
trifluoride method (Hıs, ıl, 1988). The fatty acids were
converted to their methyl esters by heating in 10%
BF3-methanol (Küsmenog˘lu et al., 1997).
Commercial mixtures of fatty acid methyl esters
were used as reference data for the relative
retention times (AOCS, 1990). Results are given as
mean values of two replicates.
2.6. Determination of mineral contents
About 0.5 g dried and ground carrot seed
sample were put into a burn