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B. Packaging and Storage of Cardamom Seeds
THE AGRONOMY AND ECONOMY OF CARDAMOM
volatiles. Hence, the powder needs more protection than the whole capsules or
seeds. The industrial and institutional requirements of cardamom are met by
grinding seeds just before use (ITC/SEPC, 1978; ITC, 1977).
Grinding is an important step in the process of converting a spice into
powder, and one has to be very cautious with a spice‐like cardamom because
it has very delicate aroma. The aroma principles of cardamom seed are
present near the surface and hence, more attention is needed during grinding
because of the heat produced in attrition. The temperature during grinding
can go up to as high as 95 C in mass production (Pruthi, 1980; Wistreich and
Schafer, 1962). For grinding, conventional mills like plate mill or hammer
mill or pin mill are employed. The particle‐size of the ground spice may vary
from 250 to 700 m, while as a flavorant for addition in food products the
preferred size will be 250–300 m. Finer particle size helps in easy release of
aroma and better mixing with food products.
Investigations on griding of cardamom at ambient conditions, using
plate mill, and low temperature, using centrifugal mill, were carried out by
Gopalakrishnan et al. (1990). In ambient conditions, using 0.25‐mm sieve led
to loss of volatiles to the extent of 52.8%, while using 0.50‐mm sieve, the loss
was restricted to 34%. However, with a coarse powder obtained by using
0.75‐mm sieve, loss of volatiles was seen to be lowered to 26.2%, but when
1‐mm sieve was used with coarser powder, the trend in the loss of volatiles was
reversed. The higher loss or poor recovery in the latter case was attributed to
the incomplete release of oil from the very coarse powder. Grinding of frozen
cardamom seeds or grinding seeds with liquid nitrogen using 0.25‐mm sieve
resulted in 35.4% and 37.8% loss of volatiles, respectively. However, cryogrinding seeds with dry ice gave the best results and the loss of volatiles was
only 8.74%, but during the grinding moisture absorption by the material was
noticed. Other studies have also shown that the loss of volatiles was considerably minimized by prechilling the spice and grinding at low temperature
(Anon, 1975, 1977).
Cryogrinding or freeze grinding of spices is a novel approach to get better
spice powder of better quality along with enhanced retention of votalies
(Wistreich and Schafer, 1962). Advantages of cryogrinding are minimum
oxidative losses of volatiles, increased output of the powder (end product)
and prevention of gumming up of screens or discs during milling (Russo,
1976). The product so obtained has good dispersibility in food preparations. It is also reported that low temperature reduces microbial load on
spices. The cost of cryoprocess gets reduced when milling operations are
carried out on a bigger scale and with eYcient recycling of the refrigerant.
K. P. PRABHAKARAN NAIR
Maximum yield of oil has been obtained when the cardamom seeds
are precooled by using liquid nitrogen to a temperature range of À180 C
to À190 C and grinding the seeds to a size of 250 m, which is, indeed, a fine
Ground cardamom loses its aroma quality rapidly by loss of volatiles and
hence proper care should be taken during storage. Gerhardt (1972) found that
lacquered cans, PVDC and high‐density polyethylene (HDPE) were suitable
for storage of powder. Koller (1976) found that vacuum‐packaged ground
cardamom stored at 5 C retained flavor for longer periods. Polyester/
aluminum foil/polyethylene laminate, with its outstanding moisture, oxygen,
and odor barrier properties can oVer a long shelf life of over 180 days under
normal conditions for cardamom powder. For shorter storage life of 90 days
and below, metalized polyester/polyethylene laminate can be considered.
Cardamom oil is obtained by distillation of powdered seeds of cardamom. Steam distillation is the most common method employed for the
production of cardamom oil. Use of the cohabitation technique for distillation has been discontinued due to the hydrolysis of esters during the process
of operation. The quality of oil depends on the variety, rate, and time of
distillation. The important trade varieties are Alleppey Green, Coorg Green,
and Saklespur bleached. Yield of volatile oil from the seeds of these three
varieties was 10.8%, 9.0%, and 8.0%, respectively (Lewis et al., 1967). External appearance, size, or bleached color are not the parameters to be considered while selecting cardamom for distillation. The high‐grade cardamom is
not economical for distillation, since it fetches a better price as whole
cardamom in the trade. Lower grades, which do not fetch higher value
because of defective appearance, but still good from the point of view of
flavor, are ideally suited for distillation. The husk is almost devoid of any
volatile oil (Anon, 1985). The flavor of cardamom is mainly due to 1,8‐
cineole, terpinyl acetate, linalyl acetate, or linalool (Table XLI). The total
flavor profile is given in Table XLII.
The United Kingdom was earlier distilling oil from the cardamom
obtained from India, Sri Lanka, and Tanzania (British Pharmacopoeia,
1980, 1993). The oil used was termed ‘‘English distilled cardamom oil’’ and
THE AGRONOMY AND ECONOMY OF CARDAMOM
The Flavor Profile (Main Components) of Cardamom Oil
Alcohols and phenols
The Composition of DiVerent Varieties of Cardamom
Volatile oil in seeds (%v/w)
Source: Data compiled from Nambudiri et al. (1968); Shankaracharya and Natarajan (1971).
Note: Moisture in the above‐mentioned raw materials ranged from 8 to 12%.
priced higher compared to the oils produced from these cardamom‐growing
countries. With the advent of better technology for the distillation of cardamom oil, the production of oil in the United Kingdom has been considerably
reduced, and the oil is being imported now.
K. P. PRABHAKARAN NAIR
G. INDUSTRIAL PRODUCTION OF CARDAMOM OIL
Cardamom capsules of proper maturity which have moisture content of
10–12% are selected for oil distillation. The capsules are cleaned with a
destoner (which removes small stones mixed with the capsules) and air
classifier to remove undesirable extraneous matter. The cleaned capsules
are dehusked in a disc (plate) mill. The gap between the discs is critical in
order to avoid damage to seeds. Seeds and broken husks are separated in a
vibratory sieve. The average composition of capsules of diVerent varieties of
cardamom is given in Table XLII.
Cardamom seeds free of husk are passed through the plate mill wherein
the gap between the discs is brought closer to get coarse powder to pass
through a 2‐mm sieve. The oil glands exist just below the epidermal layer,
and hence great care should be exercised while powdering. Fine milling
should be avoided to prevent loss of the volatiles. The powdered material
is subjected to distillation as quickly as possible. If, for any reason, there is
delay in distillation, the ground powder is packed in airtight containers until
it is used. Distillation for a 500 kg batch powder usually takes 5–6 h and may
even go up to 10 h. The rate of distillation and the condensate temperature
are carefully regulated, and it has been observed that keeping the condensate
warm helps in clear separation of oil from water (Nambudiri et al., 1968).
After commencement of the distillation, in the first 1 h about 60–70% of the
oil is collected. It has been observed that early fractions are rich in low‐
boiling terpenes and 1,8‐cineole and the subsequent fractions are rich in
esters like terpinyl acetate (Krishnan and Guha, 1950). Between varieties
Malabar and Mysore, the former contains much larger amounts of 1,8‐
cineole content and this makes it more harsh and camphoraceous, while
the oil from the latter has a sweet and fruity floral odor due to the lower
amount of cineole and higher amounts of terpinyl acetate, linalool and
linalyl acetate (Lewis, 1973). Variety Mysore is the largest selling Indian
cardamom, named Alleppey Green.
FLAVOR QUALITY OF CARDAMOM OIL
Flavor quality of cardamom oil containing high amounts of 1,8‐cineole
has been improved by fractional distillation (Narayanan and Natarajan,
1977). The authors in their experiment subjected 200 g of cardamom powder
for distillation and in the first 2.5 min collected 6.5 ml oil, of which 78.86%
was 1,8‐cineole and traces of a‐terpinyl acetate. In the subsequent period of
distillation, in the time range of 2.5 min to 2 h, of the 10.5 ml collected,
47.5% was 1,8‐cineole and 36.8% a‐terpinyl acetate. Hence, it is possible
to get good quality cardamom oil by using inferior grade cardamom by
THE AGRONOMY AND ECONOMY OF CARDAMOM
suitably collecting the oil fractions at diVerent intervals of time. Careful
blending of the fractions is carried out by keeping the aroma profile and
specifications in view. The oil yield will be less by about 25% by this method
but will be economical since the subsequent fraction fetches a higher price.
The specification of cardamom oil is given in Table XLIII.
Raghavan et al. (1991a) have standardized a method for the separation of
1,8‐cineole from cardamom oil by adduct‐formation using orthophosphoric
acid. In this method 100 ml of cardamom oil is first treated with 30 ml of
orthophosphoric acid and then with 50 ml petroleum ether with constant
stirring. The adduct (precipitate) formed is then filtered. The precipitate is
air dried and extracted with 500 ml of hot water. Cineole fraction is released
as a separate layer and recovered. The aqueous layer is extracted with 200 ml
of petroleum ether and desolventized to get terpinyl acetate rich fraction.
The gas chromotagraphy analysis of these fractions showed that cineole
fraction (28 ml) contained 80% cineole and 18% terpinyl acetate while the
terpinyl acetate fraction (58 ml) contained 76% terpinyl acetate and 16%
The Specification for Cardamom Oil
Containers and storage
Source: Adopted from EOA, 1976.
Volatile oil distilled from the seeds of
Elettaria cardamomum (Linn) Maton;
family; Zingiberaceae; cardamom grown
in South India, Sri Lanka, Thailand,
Guatemala, South China, and Indonesia
Appearance: colorless to very pale yellow liquid.
Odor and taste: aromatic, penetrating, somewhat
camphoraceous odor of cardamom; persistently
pungent; strongly aromatic taste.
Specific gravity: 0.917–0.947 at 25 C
(temperature correction factor 0.00079 C1).
Optical rotation: ỵ22 to ỵ44 .
Refractive index: 1.463–1.466 at 20 C
Solubility: 70% alcohol: in 5 volumes; occasional
opalescence: benzyl alcohol: in all proportions
diethyl phthalate: in all proportions fixed oil:
in all proportions glycerine: insoluble mineral oil:
soluble with opalescence propylene glycol:
insoluble stability: unstable in presence of strong
alkali and strong acids; relatively stable to weak
organic acids; aVected by light
Glass, aluminum, or suitably lined containers,
filled full; tightly Closed and stored in cool place,
protected from light