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Preservation of Sugar and Sugar products

Preservation of Sugar and Sugar products - Contamination of sugar and sugar products such as syrups, jams and jellies occurs mainly with bacteria which include species of Pseudomonas, Flavobacterium, Leuconostoc, Bacillus etc., and the yeasts Saccharomyces, Candida and Pichia. Honey rarely contains bacteria but contains mostly yeasts. Candies are known to contain coliforms which come during handling after processing.

These materials can be preserved by keeping the moisture level low and under dry stor­age conditions. Because of the high sugar concentration, most candies are not subject to microbial spoilage although soft fillings in chocolate covered candies may support microbial growth.

Candies are sometimes known to undergo spoilage due to growth of yeast or species of clostridia. Growth of these organisms within, can lead to explosion of candies. Spoilage of sugar syrups is mostly by osmophilic organisms includ­ing species of Leuconostoc, Bacillus and the yeast Saccharomyces and certain molds.

Syrups can become ropy because of the growth of Enterobacter aerogenes, "yeasty" as a result of growth of species of Saccharomyces or Zygosaccharomyces pink from the growth an4 pigment formation by Micrococcus roseus or moldy at the surface due to growth of species of Aspergillus, Penicillium or other fungi.

Honey, because of 'its high sugar content (70-80 per cent glucose and levulose) and a low pH (3.2-4.2) is mostly spoiled by osmophilic yeasts such as species of Zygosaccharomyces, or Torula. Sometimes, penicillia and Mucor may also grow on the surfaces. Spoilage results in the production of Co2, alcohol and non-volatile acids, which give an off flavour to the honey. Darkening and crystallization may also accompany the fermentation.

 
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