Purpose of Curing:
1) To improve quality.
2) To improve keeping quality or shelf life.
3) To avoid loss due to market glut.
4) Facilitate use in off-season.
5) Use for industrial purpose.
6) Retention of flavor.
Methods of Curing:
1) Surat Method:
a. Green ginger is soaked in water to facilitate removal of skin.
b. Skin is scrapped-off with pieces of sharpened bamboo or bits of sea shells or choir with great care and skill to avoid loss of essential oil.
c. Scrapped produce is washed and dried in sun for 3-4 days and hand rubbed.
d. It is again soaked in water for 2 h, dried and then rubbed to remove all the remaining bits of skin.
e. Sun drying also helps to bleach the produce.
f. This type of curing is rather slow but preserves the flavor and hence is beneficial.
2) Malabar Method:
a. Mainly followed in Kerala.
b. Rhizomes are soaked in 2% clear lime water [Ca (OH)2] for 6 hrs.
c. They are then transferred to sulfuring chamber for12 hrs. ;
d. The complete procedure is repeated 3 times to bleach the ginger and give it white colour before drying.
3) Caustic Soda Method:
a. Fully matured rhizomes are taken, washed and peeled.
b. They are dipped in 20 %, 25% and 50% caustic coda solution for 5 minutes, 1 minute and 1/2 minute respectively.
c. They are then transferred to 4% citric acid solution for 2 hours.
d. They are then thoroughly washed with water and dried in sun till moisture content is 15-20%.
e. Finally they are polished and packed.
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