Professor Robert Lancashire, Contributor

Ginger (Zingiber officinale Rosc.) is thought to have been introduced into Jamaica about 1525. By 1547 though, it is reported that the export of ginger amounted to over 22,000 quintals (1.2 million kg). Prior to 1740, ginger was associated with the parish of St. Ann, where it had first been planted by the Spanish. After that the Christiana region took over when it was recognised that the soil and climatic conditions were especially suitable for the growing of ginger. In 1980, a survey by the International Trade Centre reported that 1,100 acres of ginger were planted in Jamaica in the central range areas of Clarendon, Manchester and Trelawny.

Between the 1930s and 1960s, Jamaica was listed as one of the three largest producers of ginger in the world, along with India and Sierra Leone. A 10-mile radius around Christiana was identified as the region which grew the finest ginger in the world. Since then, the production has fallen significantly, from close to two million kilogrammes (kg) of ginger in 1953 to around 0.4 million kilos in 1995.

The chief constraint for production seems to be associated with peeling, as this is time-consuming and costly. An average worker can peel about 11 kg of green ginger per day, which amounts to less than three kg of dried ginger. Another problem is that it is difficult to recruit new, young staff. They are generally unwilling to take part in the peeling, which is usually left to older family members. Preparation involves removing the soil, then peeling the outer skin and spreading on mats in the sun for about 10 days in the sun, to reduce the moisture content to 10-12 per cent.

Chemistry of ginger

The sensory perception of ginger in the mouth and the nose arises from two distinct groups of chemicals:

The volatile oils, a mixture of terpenoids which imparts the characteristic aroma and modifies the taste.

The non-volatile pungent principles, such as the gingerols, shogaols, paradols and zingerone which produce the 'hot' sensation in the mouth.

The gingerols are susceptible to transformation by heat to shogaols and to compounds such as paradols (from hydrogenation of shogaols) and zingerone.

HPLC has been used to measure the ratio of [6]-gingerol to [6]-shogaol which gives an indication of the extent of pungency degradation. The lower the value the higher the pungency loss.

The extractives (oil and oleoresin) are obtained from the dried rhizomes. About two to three per cent of ginger oil is obtained on steam distillation and the main constituents include:

35 per cent zingiberene

10 per cent AR-curcumene

10 per cent beta-sesquiphellandrene

Eight per cent bisabolene

Six per cent dextro-camphene

Three per cent beta-phellandrene

Two per cent 1.8-cineole

Other important components include:

citral-a (geranial)

citral-b (neral)

a-pinene

myrcene

Ginger oil is often used for cordials and ginger wine, and preserved ginger is a very popular confection. The main markets are the United States, Western Europe and Japan.

References

The analysis and applicability of Jamaican ginger oleoeresins to the nutraceutical industry, Y.A. Bailey-Shaw, W.A. Gallimore and C.S. Reid, Jamaican Journal of Science and Technology, 2001 and 2002, Vols 12 and 13, 80-92.

'Ginger farmers gather', feature on page A14 in The Gleaner, June 15, 1996.

Ginger - A short economic history, D.W. Rodriquez, Agricultural Planning Unit, Ministry of Agriculture and Fisheries, JAMAICA, 1971.

Food Flavourings, edited by P.R. Ashurst, Blackie Academic & Professional, an imprint of Chapman & Hall, Wester Cleddens Road, Bishopbriggs, Glascow, G64 2NZ, UK. 2nd edit. 1995.

See also the ginger page by Gernot Katzer and the monograph by the Steven Foster Group.