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I. Storage of Cardamom Oil

I. Storage of Cardamom Oil

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THE AGRONOMY AND ECONOMY OF CARDAMOM



357



(Sankarikutty et al., 1982). Although the cardamom oil represents the flavor

of cardamom, it lacks the ‘‘richness’’ which is attributed to the absence of

nonvolatile components (Lewis et al., 1974). Sensory diVerences have also

been noticed between oils and oleoresins of cardamom (Govindarajan et al.,

1982b).

For oleoresin extraction, either freshly ground cardamom or essential

oil‐free cardamom powder (cardamom powder from which oil has been

distilled oV) is employed. The main considerations involved in the oleoresin

preparations are selection of suitable raw material, grinding to the optimum

particle‐size for extraction, choice of solvent, type of extraction, miscella

distillation, and blending.



K. SOLVENT EXTRACTION

Cardamom seed is ground to coarse powder of particle‐size 500–700 m,

which helps in the rupture of flavor cells and is amenable for ready extraction by solvents. Fine grinding should be avoided, which not only results in

the loss of volatiles, but also, creates problems during extraction, like slow

percolation of the solvent, channeling and engagement of the extractor for

longer periods. The powdered spice is loaded into the extractor, which is also

called percolator, and extracted with a suitable solvent. The choice of the

solvent can be from among acetone, alcohol, methanol, ethyl acetate, ethyl

methyl ketone, and so on, or a mixture of these solvents. The selection of

the solvent for extraction is a crucial step, and it should be standardized on

a small scale at the laboratory level before venturing on to commercial

production.

The selected solvent is allowed to percolate through the bed of material by

keeping the bottom drain valve open for the escape of air. When the entire

material is soaked in solvent, the bottom drain is closed, and suYcient

contact time is given for leaching of the solutes into the solvent. After the

contact time, the extract, called ‘‘miscela’’ is drained and collected.

For oleroresin production, either soxhlet extraction method (Goldman,

1949) or batch counter current extraction (CCE) is industrially practiced

(Nambudiri et al., 1970). The concentrated miscella obtained from each

extractor is carefully collected and distilled to obtain the finished product.

Most of the solvent (about 90–95%) present in the miscella is recovered by

normal atmospheric distillation, while the remaining solvent is taken oV

by distillation under reduced pressure. Great care should be exercised during

distillation to minimize heat damage to the product. After completion of

solvent stripping, the product, while hot, is discharged from the bottom still

and stored in suitable containers. It has been observed that in a 100 kg batch

extraction, the retention of solvent in the spent material is of the order of



358



K. P. PRABHAKARAN NAIR



60–70 kg and about 95% of this quantity is recovered during the desolventization process. The spent meal after the recovery of solvent is discharged

from the bottom side vent of the extractor and dried. Spent meal contains

starch, fiber, carbohydrate, protein, and so on and finds application in

animal feed composition. It can also be used as a broiler feed and as a source

of manure for crops. Cardamom spent meal has been used in the manufacture of scented sticks, used in most Indian (Hindu) homes and temples

for worship, known locally as ‘‘Agarbathi’’ (Suresh, 1987). Quality and

yield of cardamom oleoresin depends upon the raw material variety, the

solvent used and the method of extraction. By using hydrocarbon solvents,

oleoresin having 10–20% fixed oil has been obtained while with a polar solvent

like alcohol, a fat‐free product is obtained (Naves, 1974). Oleoresins containing

54–67% volatile oil have been obtained by Salzer (1975), wherein the fixed oil

content varied according to the extracting solvent. The color of the product

varies from brown to greenish brown. Kasturi and Iyer (1955) extracted cardamom seeds from which volatile oil is already distilled, using carbon tetrachloride as solvent and got 4% yield of fixed oil. The fixed oil on analysis was found

to contain 62.6% oleic acid, 18.3% stearic acid, 8.4% palmitic acid, 10.5%

linoleic acid, and 0.3% of caprylic and caproic acids. Miyazawa and Kameoka

(1975) and Marsh et al. (1977) found palmitic (28–38%), oleic (43–44%),

and linoleic (2–16%) acids as the major fatty acids present in the fatty oil.

The Central Food Technological Research Institute (CFTRI) in Mysore,

Karnataka State, has developed analytical processes for the production of

cardamom oil, spice oleoresins and encapsulated spice flavors, which have

been commercially exploited by companies involved in spice trade.

A company in the United Kingdom has claimed to have produced good

quality cardamom oil by extracting seeds with a hydrofluro solvent having a

boiling point of about –26 C. During extraction damages due to heat or

oxygen or high pH is eliminated (Anon, 1996).



1.



Super Critical Carbon Dioxide Extraction of Cardamom



Use of liquid and supercritical carbon dioxide as a solvent for flavor

extraction from plant materials has been a subject of intense study (Schultz

and Randall, 1970). Three decades back Shultz et al. (1967) used carbon

dioxide for the extraction of spices like cardamom, clove, nutmeg, coriander,

and celery. The use of carbon dioxide for flavor extraction has several

advantages over the traditional methods using other solvents.

The cheap and abundantly available carbon dioxide, which is also noninflammable, nontoxic, and noncorrosive as a solvent has merits. It has been

widely accepted as a permitted safe solvent for flavor extraction and does not

leave any residue of its own. It behaves either as a polar or nonpolar solvent

depending on pressure and temperature employed. It is liquid below its critical



THE AGRONOMY AND ECONOMY OF CARDAMOM



359



point (31.2 C, 7.38 mPa pressure) above its critical point it is safe. Under

normal conditions, density of carbon dioxide is less than 100 g literÀ1, while

under super critical conditions its density varies between 200 and 900 g literÀ1.

Naik and Maheswari (1988) extracted cardamom using liquid carbon dioxide

(20 C, 55–58 bar pressure) and using a modified high‐pressure soxhlet apparatus. They obtained 9.4% yield in 2.5‐h extraction period, while with steam

distillation in 5‐h extraction period only 9% yield was obtained. The gas–

liquid chromatography (GLC) and thin‐layer chromatography (TLC) analysis

of the extracts showed that liquid carbon dioxide extract contained slightly

higher amounts of cineole, terpinyl acetate, geraniol, and a‐terpineol (35.72%,

24.87%, 4.53%, and 11.06%, respectively) when compared to steam distilled

oil where the corresponding values were 30.25%, 22.05%, 4.22%, and 7.88%.

Extraction of cardamom under diVerent conditions of pressure, temperature,

contact time, and moisture content did not have much influence on the

yield and quality of the product. However, the extraction of nonvolatiles

and chlorophyll content increased with the increase in pressure and time.

The carbon dioxide extracted cardamom oil although has a better quality

when freshly extracted lost its fine aroma during the 90 days of storage. Quality

deterioration of the commercial steam distilled oil was comparatively less under

similar conditions (Gopalakrishnan, 1994). Table XLIV details the quality of

cardamom extracts by diVerent methods of extraction.



Table XLIV

Quality of Cardamom Extracts by DiVerent Methods of Extraction

Parameter

Yield (%)

Nonvolatile

matter (%)

Color

Aroma



Major components

1,8‐cineole

a‐Terpenyl acetate

a‐Terpeneol

Linalool

Sabinene

b‐Pinene

D‐Limonene

Linalyl acetate



SCF



Hexane extract



Clevenger distilled oil



7.7

4.6



6.2

22.5



8.3





Pale green

Superior, close

to fresh

cardamom



Pale green

Residual solvent

note, fresh

aroma absent



Colorless

Varied due to

artifact formation,

and absence of

nonvolatiles



29.7



16.6



31.2



37.0

4.6

2.6

4.1

2.8

2.4

1.6



57.3

5.0

2.3

2.2

1.7

2.2

1.6



35.5

2.4

3.8

3.4

2.8

3.3

2.1



360



K. P. PRABHAKARAN NAIR



2.



Encapsulated Cardamom Flavor



Encapsulation is a technique in which the flavorant is covered by a

suitable material thereby protecting the flavor from exposure to the environment. In this method the liquid aroma concentrate is converted to a solid

stable powder from having good shelf life. It is reported that some volatile

liquid flavors are retained in microcapsules for periods upto 2 years (Bakan,

1973). The flavor protecting material is called ‘‘wall material’’ or ‘‘encapsulating material,’’ and is generally either gum or acacia or a starch derivative

such as maltodextrin. The actual flavorant, which is to be encapsulated, is

called ‘‘core’’ material. The selected wall material should be food grade and

an eVective film former should stabilize the emulsified flavor in the process of

encapsulation. The encapsulated product is spherical and miniature in size

ranging from submicron to several millimeters (Bakan, 1978). When the

particle‐size of the capsules is less than 500 m, they are called microcapsules

(Anandaraman and Reineccius, 1980).

There are diVerent methods of encapsulation of which spray drying is

the most widely used method in the case of cardamom. Encapsulation is

also done in the case of black pepper (Raghavan et al., 1990; Sankarikutty

et al., 1988). In addition to spray drying method, there are others, such as

phase separation, adsorption, molten extrusion, spray cooling or chilling,

inclusion complex formation, and so on. In the case of spray drying, the

most popular method, the basic steps involved are: (1) preparation of

the emulsion, (2) homogenization of the emulsion with the flavorant, and

(3) atomization of the mass into the drying chamber. Raghavan et al. (1990)

have carried out spray drying of cardamom oil using a small spray drier

(Bower Engineering, NJ, USA), as well as a pilot spray drier (Anhydro). Up

to 7.2 kg yield of the dried product having 4% moisture and 8.5% volatile

oil has been obtained. After several trial batches, the optimum oil to encapsulant ratio was found to be 1.4, which very much agrees with the investigations of Sankarikutty et al. (1988). These authors have used hot water

(50–60 C) in their experiments to aid dispersion of the gum. After mixing

cardamom oil and emulsification the globule size was 2 m. The material

was spray dried at an inlet air temperature of 155 Ỉ 5 C and exit air of

100 Ỉ 5 C. For detailed information on the technique, refer Sankarikutty

et al. (1988). Under ideal conditions, the encapsulated powder should not

have any flavor. However, in practice, it has been found that the product has

mild odor due to some amount of flavor left unencapsulated and also due to

rupture of a few capsules. Attempts have been made to remove surface flavor

by washing the particles with hexane (Omanakutty and Mathew, 1985).

About 1–2% oil was found on the spray‐dried flavors made using diVerent

encapsulations.



THE AGRONOMY AND ECONOMY OF CARDAMOM



361



Gas chromatographic examination of the cardamom oils obtained from

the emulsion and their spray dried product showed a similar pattern when

compared to the original oil. However, the oil derived from the spray‐dried

encapsulated product showed a slight decrease in the cineole content (44%)

and increase in terpinyl acetate content (38.9%), while the corresponding

values in the oil obtained from emulsion were 47.4% and 34.8% (Raghavan

et al., 1990; Sankarikutty et al., 1988). Property‐wise cineole is more volatile

and has lower molecular weight than terpinyl acetate. Stability of the

encapsulated cardamom oil product was found to be satisfactory when

stored in airtight glass containers at room temperature. The moisture pick

up was negligible, and there was only 5% loss of volatile oil during the

2 years of storage period (Raghavan et al., 1990).

The following are the advantages of spray‐dried encapsulated cardamom

flavors: (1) they are nonvolatile, dry and free‐flowing; (2) can be readily

incorporated into food mixes to obtain uniform flavor eVect; and (3) flavor

stability is good over longer storage periods even at higher temperatures,

and in aqueous system the capsules break and the flavor is released.



L. LARGE CARDAMOM (NEPAL CARDAMOM)

Another type of cardamom of commercial importance is the Sikkim or

Nepal large cardamom almost equal to the small cardamom produced in the

southern states of India. Thailand, Indonesia, and Laos also produce large

cardamom to a limited extent. Large cardamom is used as a flavoring agent

in curry powders, sweet dishes, cakes, and for masticatory and medicinal

purposes. Physicochemical studies on five cultivars of large cardamom,

namely, Ramsey, Golsey, Sawney, Ramla, and Madhusey have been carried

out (Pura Naik, 1996). The studies revealed that percentage husk varied

between 27% and 31.5% and seeds 68.2–72.0%. Volatile oil content in seeds

ranged from 2.7 to 3.6%. Large cardamom contains less volatile oil than

small cardamom and is more camphoraceous and harsh in aroma with a flat

cineole color. The oil is rich in 1,8‐cineole and devoid of a‐terpinyl acetate

(Govindarajan et al., 1982b). The chemical composition of the large cardamom oil is well documented (Lawrence, 1970). Products like volatile oil,

oleroresin, encapsulated flavor, and so on, can be produced from large

cardamom also using the processing methods described for cardamom.

Products, such as volatile oil, oleoresin, encapsulated flavor, and so on,

can be produced from large cardamom also using the processing methods

described for cardamom.



362



K. P. PRABHAKARAN NAIR



M.



OTHER PRODUCTS



A number of products having cardamom as the major flavorant can be

prepared. Some of these products with commercial value are given below

(Raghavan et al., 1991b).

1. Sugar cardamom mix: It is a blend of sugar powder with encapsulated

cardamom flavor along with sunset yellow colorant and may contain

tricalcium phosphate as anticaking agent. This finds application in culinary sweets, flavoring of milk and milk products. Incorporation of the

above mix with malted ragi (finger millet, Eleusine coracana, a popular

food milltet in the State of Karnataka) flour makes a good ragi beverage,

which is very nutritious.

2. Cardamom flavored cola beverage: This is an amber‐colored sparkling

carbonated beverage containing sugar, caramel, acid, and flavors.

A market survey on this product was very encouraging and the product

was quite acceptable to the consumers.

3. Cardamom flavored ‘‘Flan’’: This product is made from milk, sugar, starch

with added color, flavor and gelling agents. It tastes like custard dairy

dessert. The formula for its preparation has been standardized by the

CFTRI in Mysore, Karnataka State.

4. Cardamom chocolate: Cardamom‐flavored milk chocolate is prepared by

using cocoa mass with butter, sugar powder, milk powder, encapsulated

cardamom flavor, and emulsifiers. The resultant product has good consumer acceptability.

5. Cardamom Plus: In West German market ‘‘Pepper Plus’’ has found favor

with consumers. This product is prepared by fortifying black pepper powder

with encapsulated pepper flavor. The advantage of this blend is its rich

naturalness with high‐flavor strength. On similar lines, ‘‘Cardamom Plus’’

can be prepared by mixing freshly ground cardamom with encapsulated

cardamom flavor. In the place of cardamom powder, cardamom residue

(subsequent to oil distillation), which contains fixed flavors, and resinous

mass, which can only be removed by solvent extraction, can be used. Spent

residue is a valuable source for making ‘‘Cardamom Plus’’ preparation.

6. Cardamom tincture: This is prepared by extraction of crushed cardamom

seeds along with other spices like caraway and cinnamon, and cochineal

using 60% alcohol as solvent. Five percent glycerin is added to the extract

which is used as a carminative mixture (British Pharmacopoeia, 1980).

7. Cardamom coVee and tea: The cardamom flavor is very compatible with

coVee and tea. The major use of cardamom in the Middle East countries is as

an additive to coVee. This cardamom is called ‘‘Gahwa’’ and it is a traditional drink with Arabs of the Gulf region (Survey of India’s Export

Potential of Spices, 1968). Encapsulated cardamom flavor is very handy

and useful while making ‘‘Gahwa’’ coVee. The flavor is incorporated into



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