Hydrated lime is essential to the production of sugar from
both sugar cane and sugar beets. It is also used to purify
sugar from other sources, such as maple or sorghum, although
these are produced in much smaller quantities.
Sugar cane and sugar beets are harvested and processed with
water to form raw juice, which has low pH and contains dissolved
impurities. Hydrated lime is added to the juice to raise the
pH and to react with the impurities to form insoluble calcium
organic compounds that can be removed. Excess lime is removed
by carbonation or by the addition of phosphoric acid. This
process may be repeated several times depending on the purity
of final product required.