Vanilla : Chemical Constituents and Uses
Biological Source, Morphology and Distribution of Vanilla:
Vanilla consists of the cured, fully grown, unripe fruits of Vanilla planifolia (Madagascar, Mexican or Bourbon vanilla) or Vanilla tahitensis (Tahiti vanilla), belonging to the family Orchidaceae. It is also known as baunilha, vanilla beans, vanilla pods and fructus vanillae.
Vanilla is indigenous to east coast of Mexico. The plant is also cultivated in Mauritius, Tahiti, Java, Seychelles, Sri Lanka and Madagascar. It is also cultivated in Kerala.
Chemical constituents of Vanilla:
The fruits contain vanillin which is chemically 4-hydroxy-3-methoxy benzaldehyde. It is present in the form of glucovanillin. It contains glycoside known as glucovanillic alcohol, which on hydrolysis gives vanillic alcohol and glucose. The oxidation of vanillic alcohol gives vanillin and it is also obtained by hydrolysis of glucovanillin. Vanillin is a cream or white coloured powder or crystals. It is soluble in fixed and volatile oils, alkali hydroxides, chloroform, ether, alcohol and is sparingly soluble in water. The odour and flavour of vanilla are collectively due to vanillin and other fragrant principles. Uses: It is used as a flavouring agent and also in perfumery.
Other sources of vanillin:
- Vanillin is present in small amounts in balsam of peru, benzoin and balsam of tolu.
- The waste sulphite liquors which are obtained in the manufacture of wood pulp is converted to vanillin.
- It is also obtained from the eugenol present in the clove oil.