Environmental Aspects of Starch Use in the Paper Industry

Starch is a rich nutrient for microbiological action and is easily degraded. Starch may spoil when exposed to high humidity. The rate of bacterial growth at 85% relative 

Microbiological action in starch dispersions results in a drop in pH, loss of viscosity and the development of odor. Retrogradation may be accelerated by the drop in pH or especially if butanol, which complexes with amylose, is generated via starch fermentation. Sulfate-reducing bacteria will cause black deposits due to reaction with iron in the process water. For quality control, preservatives are added to starch slurry, cooked starch, surface size and coating color. 

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