Question

Explain winnowing of pulses

Answer 1

In everyday life, we use a number of mixtures and one needs to separate useful components from the mixture. Thus separation of substances is performed by various methods like hand-picking, threshing, sieving and winnowing, etc. Separation can include separation of stones from rice, separating bran from flour, etc. Separation is done to remove impurities and to get a useful product. In this article we will discuss how particles are separated using the method of winnowing. Winnowing is the method in which heavier components of the mixture are separated from the lighter substances with the help of wind. This method is used for separating grains from husk after the process of threshing. Threshing is the process of separating grain from chaff. In this process, a mixture of wheat and husk is dropped from a height. After that, husk is carried by the wind and forms a heap at some distance away. The husk being lighter is carried away by the wind and forms a different heap. The heavier particle (wheat grains) forms a separate heap as it falls vertically downward. To separate dirt from pulses, we add water to pulses. Dirt will get dissolved in water and husk will float on top because it is lighter and pulse grains will settle down.

Advantage of Winnowing:

This method doesn’t require any machines for its functioning. It is completely based on human activity and hence it takes less time to process and definitely very cheap.

Disadvantage of Winnowing:

Winnowing is defined as a method in which heavier components of the mixture are separated from the lighter substances with the help of wind but this process does not work for materials heavier than grains like stones.

Answer 2

The act of separating chaff from grain.