Influence of rheological properties and pull-off forces of native and modified starches on cleaning in plane channel flow

Abstract

Consumer safety and product quality are of high priority in the food industry. Strongly adhering deposits are formed in processing equipment such as plate heat exchangers, which demand large quantities of water, chemicals, energy and time for cleaning. This study presents an approach to characterize soil properties and to link them to the cleaning behavior to generate a basis for soil-specific cleaning. Six starch soils were rheologically analyzed during swelling, pull-off forces were measured with a micromanipulation device, and swelling progression was determined with a camera. Cleaning experiments were conducted in a plane channel setup. A reptation time without cleaning and a subsequent constant cleaning rate defined the cleaning behavior. The observed cleaning mechanisms were considered as well. Multivariate statistics revealed significant interrelationships between soil properties and cleaning behavior. The complex reasons for the overall cleaning behavior remain unknown, but certain aspects could be explained by the measured soil properties.