Chemistry and microbiology in sugar extraction

The stability of the sucrose molecule and the firmness of the tissue structure in the cossettes are of major concern when optimizing the operating conditions for the extraction system. For a given extraction system the retention time is more or less fixed, but the actual pHvalues and temperatures to be set across the system largely determine the extent to which both sugar gets lost by hydrolysis and the cossette structure deteriorates, particularly by dissolution of pectin. Furthermore, potential sugar loss by microbial infection in the extraction system needs to be controlled too. The influence of the pHvalue and temperature on these undesirable chemical and microbial reactions will be outlined in this paper, including the consequences for the subsequent processing steps. It can be concluded that the recommended optimal pHvalues and temperatures for operating the extraction system are a compromise between good and bad.