Turmeric Powder Processing

Removing all kinds of impurities is very important before curing or drying the turmeric. The leaves from the plant are removed and the roots are cleaned to get rid of the soil. At this point, the turmeric finger rhizomes are separated from the mother rhizomes. Both mother and finger rhizomes are heaped apart for manual or machine cleaning.

Removing all kinds of impurities is very important before curing or drying the turmeric. The leaves from the plant are removed and the roots are cleaned to get rid of the soil. At this point, the turmeric finger rhizomes are separated from the mother rhizomes. Both mother and finger rhizomes are heaped apart for manual or machine cleaning.

The rhizomes are sliced by hand and then they are sun-dried. This improves the quality of the final product. Usually, the rhizome bulbs and fingers are laid down on a clean concrete floor. But care must be taken to place the rhizomes not under direct sunlight as it would impact the color of the turmeric.

Dried rhizomes with rough and uneven surfaces need to be polished. Polishing removes the small roots, rough surface scales, and any remaining soil particles. It even helps to obtain a better surface finish. Polishing of the rhizomes can be carried out manually or mechanically. For manual polishing, the dried turmeric is put inside gunny bags and rubbed along a hard surface. But for mechanical polishing, power-operated drums are used.

It must be kept in mind that polishing turmeric is not a compulsion if it’s going to be used for solvent extraction and also for use as a color. A part of the polishing process is destoning. It helps to polish the surface of the dried rhizomes.

This process involves cutting and even crushing down the dry rhizomes before grinding them. One must cut the dry rhizome bulbs or fingers into fine pieces and place them in the grinding machine for crushing the rhizomes. Different types of grinding machines are available depending on the fine or coarse powder requirement. For getting high-quality ground turmeric, the grinding temperature is kept very low by the mill operators.

Once the grinding is complete, the powder is made to pass through a sieving machine and a magnet separating machine. The powerful magnets help to remove any kind of metallic impurities in the powder. On the other hand, the grounded powder is sieved with the help of various mesh screens, till a fine and uniform ground powder is attained.