Milling is a crucial step in post-production of rice. The basic objective of a rice milling machine https://www.victorricemill.com/ is to remove the husk and the bran layers, and produce an edible, white rice kernel that is sufficiently milled and free of impurities.
The rice kernel composition,Most rice varieties are composed of roughly 20% rice hull or husk, 11% bran layers, and 69% starchy endosperm, also referred to as the total milled rice.
Depending on the requirements of the customer, the rice should have a minimum number of broken kernels.In an ideal rice mill plant https://www.victorricemill.com/products/rice-mill-plant/ this will result in the following fractions: 20% husk, 8−12% bran depending on the milling degree and 68−72% milled rice or white rice depending on the variety. Total milled rice contains whole grains or head rice, and brokens. The by-products in rice milling are rice hull, rice germ and bran layers, and fine brokens.
The best quality rice will be attained if the quality of paddy is good and the rice is milled properly. To improve the quality of the rice, factors such as the paddy quality and milling technology should be considered.
To obtain good paddy quality:
postharvest-measure-moisture-content
Mill at the right moisture content, moisture content of 14% is ideal for milling.
If the moisture content is too low, high grain breakage will occur resulting in low head rice recovery. Broken grain has only half the market value of head rice. Use a moisture meter to determine the moisture content. Visual methods are not accurate enough.
postharvest-pre-clean-paddy
Pre-clean paddy before husking
Use of paddy without impurities will ensure a rice cleaning machine and higher quality end product.
Do not mix varieties prior to milling
Different varieties of paddy have different milling characteristics that require individual mill settings. Mixing varieties will generally lead to lower quality of milled rice.
When using milling technology
Use rubber roll technology for husking
Rubber roll paddy rice huller machine https://www.victorricemill.com/product/paddy-rice-huller-machine-for-sale/ produce the best quality. Engleberg-type or "steel" hullers are no longer acceptable in the commercial rice milling sector, as they lead to low milling recovery and high grain breakage.
postharvest-rubber-roll-techUse a paddy separator
Separate all paddy from the brown rice before whitening. Paddy separation after husking will lead to better quality milled rice, and reduce overall wear and tear on the rice mill.
Consider two-stage whitening
Having at least two stages in the whitening process (and a separate polisher) will reduce overheating of the grain and will allow the operator to set individual machine settings for each step. This will ensure higher milling and head rice recovery.
postharvest-screen-sifter Grade the milled rice
Installl a screen sifter to remove small brokens and chips from the polished rice. Rice with a large number of small brokens (or brewer’s rice) has a lower market value. The small brokens can be utilized to produce rice flour.
Monitor and replace spare parts regularly
Turning or replacing rubber rolls, refacing stones, and replacing worn screens regularly will keep milled rice quality high at all times.