Oil of Star Anise

The extent of super-cooling has a slight effect upon the final temperature noted, and it should therefore be as small as possible. Alow congealing-point may either be due to a low anethole content or to the fact that as the oil ages certain of its constituents polymerise and cause a depression. 

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The seeds contain some volatile oil, resin and a large amount of fixed oil (Meisner, 1818). The fruit (without the seeds) contains volatile oil, resin, fat, tannin, pectin and mucilage. The volatile oil (oil of star-anise) amounts to about 4-5% and is almost identical with oil of anise (from P. anisum, LinnS). Star-anise oil from Chinese fruit has a specific gravity at 15°C (59°F) of 0.980-0.990 and its known constituents are anethol, phel-landrene, safrol and hydro-quinone-ethyl-ether (Fliickiger, 1879). Poisonous sikimin has been detected in the fruit (Eykmann, 1881), while Schlegel (1885) found a crystalline principle of a pronounced odour of musk. He also found saponin in the watery extract. 

Star anise contains primarily anethole and fatty oil. Essential oil of star anise has a sweetish, burning flavour and a highly aromatic odour. It is located primarily in the woody shell and, to a lesser extent, in the seed. An elevated moisture content and excessively high temperature create a risk of self-heating. 

The GC-MS pattern of fruit volatile oil of star anise (7. vemm Hook) shows the presence of 25 components, which account for 99.9% of the total amount (Padmashree et al., 2007). The major components are trans-anethole (93.9%), estragole (1.05%) and limonene (1.05%) (Table 17.3). Fifteen components are identified from its acetone extract, accounting for 80.27% of the total amount. frans-Anethole (51.81%) is found as a major component, along with linoleic acid (11.6%), l-(4-methoxyphenyl)-prop-2-one (6.71%), foeniculin (5.29%) and palmitic acid (1.47%). 

Oil of star anise, Chinese type (Illicium verum Hook, f.)... 

The main component of star anise oil, as in anise oil, is /rans-anethole (86 93%) [779 782bj. Pure anethole can be obtained by rectiflcation (see p. 127). Star anise oil has replaced true anise oil derived from Pimpinella anisum in the production of natural anethole. 

Tuan, D.Q. and Hangantileke, S.G. (1997) Liquid C02 extraction of essential oil from star anise fruits (lllicium verum H.). Journal of Food Engineering 31,47-57. 

Vietnam produces more than 50001 of star anise seeds per annum. It is estimated that the combined production of China and Vietnam is more than 25,0001 per annum. In addition, 200-2501 of essential oil are shipped to France and the Czech Republic. In China, which is the largest supplier of star anise to the world market, Vietnamese star anise is blended and then exported to France. In France, it is used as a raw material in the production of alcoholic beverages (FAO, 2003). 

Table 17.1. Physical properties, extraction yield and anethole content of star anise essential oil.

Fig. 17.1. Components of essential oil from star anise (/. verum).

The essential oil from star anise fruits traditionally is extracted by steam distillation. This process is not expensive but can induce thermal degradation, hydrolysis and water solubilization of some fragrance constituents (Reverchon, 1997). 

Table 17.3. Flavour profile of star anise volatile oil.

Rudzki, E. and Grzywa, Z. (1976) Sensitizing and irritating properties of star anise oil. Contact Dermatitis 2(6), 305-308. 

Singh, G., Maurya, S., deLampasona, M.P. and Catalan, C. (2006) Chemical constituents, antimicrobial investigations and antioxidative potential of volatile oil and acetone extract of star anise fruits. Journal of the Science of Food and Agriculture 86(1), 111-121. 

Table IV. Comparative Chemical Composition of Star Anise Oils...

Inhibitory Data of Star Anise Oil Obtained in the Agar Diffusion Test ... 

The analysis of the oil has been reviewed by Lawrence [49]. Extraction of star anise with S.CO2 has been reported by Calame and Steiner [13]. At a pressure of 300 bar and 40°C for extraction and a subsequent fractionation at 55 bar and 37°C they obtained an oil at a 12.1% yield and an 85% volatile oil content. Subsequent experiments with hexane as an entrainer with CO2 did not improve the extraction. These results are similar to this author s research with liquid CO2 which are being prepared for publication. Earlier pioneering work by Stahl [43] was published, which included a comparison of steam distillation and CO2 extraction of star anise, anise, caraway, clove and cinnamon. 

The star anise (I//icium verumHook E.) is from a smaH evergreen tree, native to southwest China. When ripe, the hard brown fmits of this tree open up into an eight-pointed star, hence the name. The flavor and aroma of this spice is similar to that of P. anisum, the essential oils are of similar composition. The uses are similar but more localized. 

Badflfissigkeit, /. bath liquid, bath solution. Badian, m. Chinese anise, star anise, badian Illicium verum). -ol, n. star anise oil. badisch, a. of Baden. — badische Saure, badische acid, 2-naphthylamine-8-sulfonic acid. 

The oil was formerly produced in many countries, mainly in eastern Europe, but has now been replaced, to a large extent, by the less expensive star anise and fennel oils which also contain a high percentage of anethole. 

Star anise oil is obtained by steam distillation of the star-shaped fruits of Illicium verum Hook. f. (Illiciaceae), an evergreen tree growing in Vietnam and China. It is a colorless to pale yellow liquid, which solidifles on cooling. 

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