Curing and Processing of Turmeric
* Quality and proportion of cured and dry produce to green produce depends on the variety.
* Mother rhizomes have higher curing percentage than ‘fingers.
Processing of Turmeric:
Polishing (Rubbing and Polishing Drum)
1. Cleaning: Done by removing soil adhering to rhizomes and fingers.
a) Cleaned fresh rhizomes are kept in tin pan.
b) While boiling, the water level should be 5-7 cm above the rhizomes
c) For quick and proper boiling, the rhizomes are covered with turmeric leaves 5-7 cm in thickness and plastered with mud and cow dung.
d) Due to use of cow dung, fingers get artificially coloured with lead chromate (chemichrome) which is poisonous. To avoid this CFTRI, Mysore has proposed to boil rhizomes in lime water (20 g Na2C03 + 20 ml HC1 per 50 kg rhizomes).
e) Boiling is continued for about 1.5 hour.
f) The rhizomes are boiled in water till froth comes out and white fumes appear giving out a characteristic odour.
g) To test proper cooking a matchstick is pierced through the boiled rhizomes. If it passes easily through the rhizomes, the material is said to be cooked.
h) Over cooking spoils the colour and fingers become light and get broken during polishing.
a) Rhizomes after cooking are stored in a heaps for over night and then spread over a hard and clean ground.
b) Drying is carried out for 8-15 days.
c) The material is stirred 2-3 times to ensure uniform drying.
d) Improper drying results in the rhizomes become hard or brittle.
e) The rounds and fingers are marketed. Few. bulbs, are sold as most of them are used for planting.
a) Mother rhizomes and fingers if cooked together are separated before polishing.
b) In Maharashtra only fingers are marketed. Few bulbs are. sold as most of them are used for planting.
5) Polishing: Boiled and dried turmeric has rough and hard outer surface.
Object of Polishing:
a. To smoothed external surface of rhizome.
b. for colour improvement.
Methods of Polishing:
a) Rubbing against hard surface or trampling under feet after wrapping in gunny bags.
b) Polishing Drum:
* Used in Maharashtra.
* Manually operated
* Capacity, 20-30 kg per rotation,
* Turmeric polished by smooth end has better colours and quality.