4. Ginger
Synonyms Gingerin.
Biological Source It is the oleoresin obtained by the method of percolation of the powdered rhizomes of Zingiber officinale Roscoe, belonging to the Family: Zingiberaceae.
Preparation The rhizomes are sliced, dried and powdered. The powdered ginger is extracted either with acetone or ether or ethylene dichloride by the method of cold percolation repeatedly till the gingerin is no longer present in the marc. The solvent is removed by distillation under reduced pressure. Ethanol gives the max yield of the oleoresin. The average yield of the oleoresin is 6.5% but it may range between 3.5 to 9.0% based solely upon the source of the plant product and to a great extent on the technique adopted in the course of preparation.
Characteristic Features It is a dark brown, aromatic and pungent viscous liquid.
Chemical Constituents Ginger contains volatile oil (1-3%), which comprises of zingiberene, α-curcumene, β-sesquiphellandrene and β-bisabolene. Zingiberene (a) has two chiral centres.
The acyclc chiral centre has been stereochemically related to that in (+)-citronellal, and the cyclic chiral centre to that in (–)-phellandrene. Hence, (–)-zingiberene has the absolute configuration
(b). The oleooresin contains the pungent gingerols and shogaols.
Uses
1. It is used as a flavouring agent, carminative, aromatic and stimulant to gastrointestinal tract (GIT).
2. Ginger finds its wide applications in soft drinks, beverages, ginger beer and wine.
3. It is extensively used for culinary purposes in ginger-bread, biscuits, puddings, cakes, soups and pickles.
