Wind winnowing is an agricultural method used from ancient times during the harvest time, for separating grain from chaff or husk. A winnow is also used to clean stored grains like rice, daals, etc of unwanted elements like husk, dirt, small insects/pests etc in the Indian kitchens. Some winnows smeared with turmeric and kumkum are used for certain religious ceremonies too in India.

Winnows are commonly used in rural India. In urban India metal ones are used as they are easy to clean. Winnows are used in other Asian countries too mostly in agricultural areas.
The form of the winnow is very simple. It is like a flat mat on one end which slopes down and ends, curved like a small container. The entire winnow is strengthened by thick strips of bamboo on the sides. The traditional ones are woven out of bamboo or cane strips. In the present day they are available in aluminium and stainless steel too.

Winnowing involves taking the grains to be cleaned in a winnow, holding it with both the hands and throwing the mixture into the air so that the wind blows away the lighter chaff, and the heavier grains fall back down into the container area.

A traditional form of winnow in bamboo strips
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Winnow being used
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