The starch adhesive is subject to microbial contamination and attack (spoilage). The result can be a loss of viscosity of the combining adhesive. Viscosity loss can have significant detrimental effects on quality and productivity. In short, unless precautions such as the following are taken, the adhesive preparation, storage and circulation system can act as a large fermentation system, since starch, especially the cooked or carrier portion that provides viscosity, can provide a food source for microbes.