Mother Liquor Definition in Chemistry

Spoon and molasses
Molasses is the mother liquor from the cane sugar refining process.

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Mother liquor is a deprecated term from older chemistry texts that refers to the solution that remains after crystallization occurs and the crystals are removed. Initially, crystallization occurs in a supersaturated solution that is usually prepared by heating a solution and continuing to add solute until no more will dissolve. After crystals have grown, the liquid is filtered out at retained (the mother liquor). This liquid contains some original solute, plus other impurities that were not incorporated into the crystal. Often, more crystals can be grown from the mother liquor.


Molasses is made from the mother liquor produced by the cane sugar refining process.


  • Lehman, John W. (2008). Operational Organic Chemistry (4th ed.). Pearson. ISBN: 978-0136000921.