Like any grain processing, small millet processing involves three primary tasks:
- Size Grading
- Density Grading
- Hulling (also referred to as dehusking)
An eccentric or vibrating grader is used to achieve size grading, a destoner is used for density grading and an impact or shear huller is used for hulling.
Most people talking about millet processing invariably focus on the hulling and do not consider the complications in the other two task. Standard grain cleaning and grading machines available in the market come up short when used for small millets because the primary design factor – the size of the working material, the grain size – is so different. Proper cleaning and grading of the input material to the huller allows for proper cleaning and grading of the output material. And equally importantly it helps better retain the nutritious bran layer.
More information on each of these steps shall be shared in upcoming posts.