Handbook of Herbs and Spices - Volume 3

(sharon) #1

284 Handbook of herbs and spices


dried exhausted and pulverized caraway chaff contains 20–23.5% crude protein of


which 75–85% is digestible and 14–16% is fat and can be used as an ideal cattle feed.


The chaff oil is obtained by steam distillation of material left after threshing of fruits


and contains less carvone and more terpenes. It has less of the characteristic odour of


the seed oil and is harsher with a somewhat bitter taste. This is produced on a very


small scale and is also used as an adulterant of the fruit oil.


15.4.6 Herb and root oil


Caraway herb oil is obtained by steam distillation from fresh whole plant, stalks,


leaves and seeds. The top stem is usually prepared for the distillation process and


stems are removed. Some growers feel that it should be harvested before flowering


and others say it is better afterwards. Caraway herb oil has similarity in flavour with


oil extracted from seed and could quickly expand to commercial production as an


alternative to seed. The root oil can also be obtained by distillation of minced roots


and consists mainly it oxygenated compounds with aldehydes up to 70% including


octanal, nonanal, cis-dec-4-enal and trans-dec-2-enal. The complete analysis of herb


oil and root oil in comparison to essential oil extracted from seed is not available but


it is considered that it is inferior in quality to seed oil and is also used as an adulterant


of fruit oil.


15.4.7 Caraway carvone


The essential oil constituent d-carvone is a nearly colourless to pale yellow liquid,


which darkens with age. The odour of caraway carvone is warm, herbaceous, bread-


like, spicy and slightly floral. The taste is sweet, spicy and bread-like. The carvone


reportedly has certain cancer-preventive properties and anthelmintic properties. Pure


carvone is prepared by decomposing crystalline compounds of carvone with hydrogen-


sulphide. Carvone also has uses in the soap industry for addition of natural aroma.


Demand for carvone fluctuates and is confined to a particular segment of the market


but regular extraction of carvone can become an alternative to caraway seed in the


food-processing and pharmaceutical industries.


15.4.8 Decarvonized oil


Decarvonized oil consists of limonene with traces of carvone and is sold on the


market as light oil of caraway. It finds use in scenting soaps. At the beginning of


distillation the essential oil has higher carvone, whereas at the end limonene


predominates. The reason is that carvone is an oxygen-containing compound and is


several times more soluble in water than limonene.


15.4.9 Caraway oleoresin


The oleoresin of caraway fruit is prepared by extraction of crushed dried seed with


suitable volatile oil solvents like food-grade hexane ethanol, ethyl acetate or ethylene


dichloride; filtration and desolventization under vacuum. The organic solvent should


be recovered completely from oleoresin as per the ISO, as well as the fixed maximum


permissible limits for the approved solvents of the importing countries. Caraway


oleoresin is one of the most valuable flavouring agents as it imparts warm, aromatic

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