The molasses desugarization process takes the by-product, molasses, left over after the crystallization processes and separates it into sugar-rich and salt-rich syrups. Molasses enters the process at 60 to 65 % sucrose purity. The molasses desugarization process uses an ion exclusion process to produce a 90 to 93 % purity sucrose syrup extract. The remainder forms a by-product sold as a feed supplement called Separator Molasses Solubles (SMS), which is essentially molasses with the sugar removed.

The separation process itself is accomplished by pushing diluted molasses through tightly backed beds of very small beads of ion exclusion resin with a stream of water. The process utilizes the molecular structure and size of the different components in molasses to separate the sugars from the non-sugars in the liquid. Sucrose molecules are attracted to the resin beads, while the resin beads repel the majority of the non-sugars. Various sized molecules of the various non-sugar components also have their progress retarded while passing through the bed, dependent upon their size, by the very tightly packed resin beads. The resin bed is placed in special columns that allow liquids to enter and leave but keeps the resin in place with a screened distribution system.

As the diluted molasses is fed into the column of resin, pushed by a stream of water, the non-sugars pass through the space left void by the resin. The sugar, attracted to the resin bead, will enter the resin through the porous surface of the bead. As the solution passes through the resin column the non-sugars will be the first to reach the bottom since they traveled only through the void spaces in the column. Various non-sugar molecules will travel at various known speeds, depended upon size. Then, as the liquid passes through the column, a valve can be opened at the bottom of the column to take the non-sugar syrups out of the column based on those known times. Sugar is the last molecule to reach the bottom of the column, as the water stream pushing the dilute molasses, washes the sugar from the resin beads, moving the sugars to the bottom of the column last. As the sugar solution reaches the bottom of the resin column a valve is opened to take the sugar solution to an extract tank. Then a fresh shot of diluted molasses is sent through the column.

The sugar-rich syrup and the by-product solutions are taken to separate sets of evaporators to remove excess water. The sugar solution will join the thick juice extracted from the sugar beets and be crystallized in the sugar end crystallization processes. The other product is sold as liquid.

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