Inversion

INVERSION (from Latin inversio - turning upside down), the hydrolytic cleavage of cane sugar (sucrose) into its components: fructose (levulose) and glucose (dextrose). C₁₂H₂₂O₁₁ + H₂O = C₆H₁₂O₆ + C₆H₁₂O₆. Cane sugar rotates the plane of polarization to the right (a_D = +66.5°), while among the products of decomposition, fructose rotates to the left (a_D = -93° or -94°), and glucose rotates to the right (a_D = +52.5°). Since the left-handed rotation of fructose is stronger than the right-handed rotation of glucose, and equimolecular amounts of both monosaccharides are formed during the decomposition of sucrose, the resulting mixture, so-called invert sugar, possesses left-handed rotation, i.e., opposite to the original rotation of sucrose. Hence the term Inversion, indicating the reversal of optical activity. The inversion of cane sugar can be caused by acids or the enzyme sucrase. Acidic inversion proceeds according to the type of monomolecular reactions, and its study once served as the starting point for the development of the kinetics of chemical reactions. Since the rate of acidic inversion is directly dependent on the concentration of H-ions, the determination of the rate of inversion can serve as one of the methods for determining active reaction. Invert sugar is used as a substitute for honey (artificial honey) and in the confectionery industry.