Table of Contents:

Chemistry

Typical allspice, on analysis, shows about 6% protein, 6.6% crude fat, 52.8% carbohydrate, 21.6% crude fiber, minerals such as calcium, phosphorus, sodium, and potassium, and water-soluble vitamins.

However, the most important constituent of allspice is the essential oil, which is present to a level of 3-4.5% on a dry basis. The characteristic aroma is influenced by the main constituent eugenol (see Chapter 36 on Clove).

Essential Oil

Allspice seeds from three sources have been analyzed for volatile oil content and yield of resin by solvent extraction of the deoiled residue. For this, deoiled material is dried and extracted by cold gravity percolation using hexane as the solvent. The results are presented in Table 14.1. Jamaican allspice shows a higher yield of both oil and oleoresin.

Commercial steam distillation using external steam and a stainless-steel still is carried out. Size reduction is done using a roller mill where round berries are turned into flat flakes. Steam is let in at a slow rate at normal pressure for a period of 18 hours. Most of the oil is heavier than water, with a small quantity being lighter. On mixing, the total yield is 4.0%.

A typical GC analysis of Jamaican allspice oil is presented in Table 14.2.

Much analytical work carried out has shown that the allspice oil contains mainly methyl eugenol and eugenol. There are some minor components that will naturally

Table 14.1. Analysis of pimenta from different sources

Origin

Volatile Oil (vo) Content

Resin (%) by

Total Yield

Clevenger Method, Water

Hexane Extraction

of Oleoresin

Distillation (% v/w)

(vo + Resin)

Jamaica

3.2

5.0

8.2

Mexico

2.3

4.7

6.8

Guatemala

1.8

4.0

5.8

Table 14.2. GC analysis of Jamaican pimenta oil (area percentage)

Constituent

Percentage Range

Eugenol

80-87

p-Caryophyllene

4-8

p-Phyllandrine

0.2-0.5

1,8-Cineole

1-3

a-Pinene

<0.3

p-Pinene

<0.3

6,-3-Carene

0.5-2

Limonene

<0.5

influence the quality of the oil. Lawrence (2006) has compiled this list into a useful review, for further information. Studies (Padmakumari et al., 2011) show that eugenol, quercetin, and gallic acid that are present exhibit antioxidant properties.

Pimenta berry oil is a heavy yellow to reddish-yellow clear oil with a fine aroma reminiscent of clove, cinnamon, nutmeg, and black pepper. It turns darker on storage.

According to the FCC, pimenta oil occurs as a colorless, yellow or orange liquid that becomes darker with age. It has the characteristic odor and taste of allspice. It is soluble in alcohol, in propylene glycol, and in most vegetable oils.

Physical characteristics as defined by the FCC are as follows:

Optical rotation Refractive index Specific gravity Solubility

  • -4 to 0°
  • 1.527-1.540 at 20 °C 1.018-1.048
  • 1 mL dissolves in 2 mL of 70% alcohol
 
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