4. Conclusions
By comparing the deterioration (at 27
C) of heat-
and biocide-treated cane juice with untreated juice, it
was possible to quantitatively compare the relative con-
tributions of microbial, enzymic, and chemical dete-
rioration on sucrose losses. Over the first 14 h of
deterioration, 93.0% of sucrose deterioration was
microbial, 5.7% enzymic and 1.3% was chemical (acid
degradation). Ion chromatography with integrated
pulsed amperometric detection (IC–IPAD) was used to
simultaneously analyse for ethanol, mannitol, and oli-
gosaccharides in deteriorated cane juice. The rate of
formation of mannitol, produced from the reduction of
fructose by mannitol dehydrogenase in dextran-forming
Leuconostoc bacteria, was much higher than associated
oligosaccharides or ethanol formation. A further inves-
tigation of the use of mannitol as a sensitive indicator of
future dextran-related processing problems at the fac-
tory is warranted. Ethanol was shown not to be very
useful as an indicator of cane Leuconostoc bacterial
deterioration. There is now a need to undertake further
deterioration studies, with different sources of cane juice
and specific inoculations, with yeast and Leuconostoc
bacteria, which are frequently found in cane juice.