Like any other industry, maize milling has its unique processes and terminology. Here’s a simple explanation of how a maize mill works and the processes that can take place during the production of maize meal and bran, depending on the set-up and size of the milling operation, and the type of maize meal required (community, super, special or very fine maize meal).
1. Cleaning / Pre-cleaning of raw maize
The raw maize is fed into the plant where it will first undergo the cleaning stage.
This step improves the quality of the final product. It’s vital that foreign material such as husks, straw and dust is removed using slotted screens or aspiration. As an extra precaution, a magnet is used to remove metal that could damage milling equipment. This process prolongs the lifespan of the mill and milling equipment.
Roff recently introduced a new pre-cleaner to its range, the CLR 107. offering a bigger capacity of 18 tons per hour. As the CLR 107 is manufactured locally, it's more cost effective and has a short lead time.
Cleaning or pre-cleaning is done by hand with a simple table screen at community mills.
Conditioning is the addition of water to get the germ and bran moist for optimal removal/separation. Controlled humidity increases the effectiveness of degermination and improves maize meal quality. Conditioning combined with a degerminator gives the best results.
This process removes the germ from the endosperm to achieve a more refined maize meal and to prolong the end product’s shelf life. The by-product can be used as an ingredient in animal feed, further adding to profitability.
Milling and sifting
This step entails a combination of rollers and screens that break the product down to maize meal and removes the remaining bran before packaging.
During the final step, the product is packaged as maize meal. It can either take place manually, or via a semi-automatic or automatic process. Apart from the operational aspects involved in packaging your product you also need to consider how your product packaging looks. We have some handy packaging design tips here.