Selective oxidation of colour-inducing constituents in raw sugar cane juice with potassium permanganate.

Author(s) Fang, Y.; Ellis, A.; Uchimiya, M.; Strathmann, T.J.
Journal Food Chem
Date Published 2019 Nov 15
Abstract

Colour removal in raw sugar remains a crucial but expensive process in the sugar industry. In this report, permanganate (MnO) oxidation is explored as an alternative method to remove colour-inducing constituents in sugar cane juice/produced raw sugar. Experiments indicated alum, an inexpensive coagulant, was able to remove residual Mn species produced after MnO treatment. The optimal dosages of MnO and alum for decoloration of a 17 wt% raw sugar solution (70 °C) was found to be 4 mM and 2 g/l, respectively. Removal of colour and Mn removal were further improved at ambient temperature. Sucrose, the major component of raw sugar, was not affected during treatment with MnO and alum. Two-phase kinetic behaviour for MnO oxidation was observed, where an initial rapid oxidation phase is followed by a second slower reaction phase. These results suggest permanganate oxidation is a promising alternative for accomplishing the decoloration of raw sugar solutions.

DOI 10.1016/j.foodchem.2019.125036
ISSN 1873-7072
Citation Fang Y, Ellis A, Uchimiya M, Strathmann TJ. Selective oxidation of colour-inducing constituents in raw sugar cane juice with potassium permanganate. Food Chem. 2019;298:125036.