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B. Packaging and Storage of Cardamom Seeds

B. Packaging and Storage of Cardamom Seeds

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THE AGRONOMY AND ECONOMY OF CARDAMOM



351



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).



D. GRINDING

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.



352



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

powder size.



E.



STORAGE POWDER



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.



F.



CARDAMOM OIL



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



353



Table XLI

The Flavor Profile (Main Components) of Cardamom Oil

Components

a‐Pinene

b‐Pinene

Sabinene

Myrcene

a‐Phellandrene

Limonene

1,8‐Cineole

y‐terpinene

p‐Cymene

Terpinolene

Linalool

Linalyl acetate

Terpinen‐4‐ol

a‐Terpineol

a‐Terpinyl acetate

Citronellol

Nerol

Geraniol

Methyl eugenol

Trans‐nerolidol



Content (%)



Trace components



1.5

0.2

2.8

1.6

0.2

11.6

36.3

0.7

0.1

0.5

3.0

2.5

0.9

2.6

31.3

0.3

0.5

0.5

0.2

2.7



Hydrocarbons

a‐Thujene

Camphen

a‐terpinene

cis‐Ocimene

trans‐Ocimene

Toluene

p‐Dimethylstyrene

Cyclosativene

a‐Copaene

a‐Ylangene

y‐Cadinene

y‐Cadinene

Acids

Acetic

Propionic

Butyric

2‐Methyl butyric

3‐Methyl butyric



Alcohols and phenols

3‐Methyl butanol

p‐Menth‐3‐en‐l‐ol

Perillyl alcohol

Cuminyl alcohol

p‐Cresol

Carvacerol

Thymol

Carbonyls

3‐Methyl butanal

2‐Methyl‐butanal

Pentanal

Furfural

8‐Acetoxycarvotanacetone

Cuminaldehyde

Carvone

Others

Pinole

Terpinyl‐4‐yl acetate

a‐Terpinene propionate

Dihydro‐a‐terpinyl acetate



Table XLII

The Composition of DiVerent Varieties of Cardamom

Variety



Husk (%)



Seeds (%)



Volatile oil in seeds (%v/w)



Kerala State

Alleppey Green



26.0–38.0



62.0–72.3



7.5–11.3



Karnataka State

Coorg



25.2–28.0



69.6–73.3



7.5–9.1



Tamil Nadu

Yercaud



24.0–33.0



73.0–76.0



6.5–9.6



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.



354



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.



H. IMPROVEMENT



IN



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



355



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%

cineole.



Table XLIII

The Specification for Cardamom Oil

Definition, source



Physical and

chemical constants



Descriptive characteristics



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



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