1. Introduction -- 1.1. Motivation -- 1.2. Aim of the present work -- 1.3. Outline -- 2. Background of cleaning in place -- 2.1. Heat treatment in the dairy production -- 2.2. Fouling and cleaning in the dairy production -- 2.2.1. Heat-induced formation of fouling deposits -- 2.2.2. The use of whey protein for experimental studies -- 2.2.3. Cleaning process for the fouled heating surface -- 2.3. The influence factors of cleaning in place -- 2.4. Cleaning mechanisms on the mechanical properties of protein deposits -- 3. Mechanical behaviour of heat-induced deposits -- 3.1. Mechanical behaviour of fouling deposits -- 3.1.1. Fouling experiments with raw milk and whey protein solution -- 3.1.2. Realisation of quasi-static and dynamic indentation experiments -- 3.1.3. Comparison of mechanical responses between milk and whey protein deposits -- 3.1.4. Influences of heat treatment on the mechanical behaviour of fouling deposits -- 3.2. Mechanical behaviour of whey protein gel -- 3.2.1. Gelation of whey protein solution with different heating conditions -- 3.2.2. Characterisation of fracture behaviour of WPG -- 3.2.3. Degradation of the WPG samples with NaOH solution -- 3.2.4. Characterisation of failure behaviour of WPG -- 4. Constitutive modelling and numerical simulation 69 -- 4.1. Kinematics and balance equations -- 4.1.1. Kinematics of deformation -- 4.1.2. Stress tensors -- 4.1.3. Balance equation -- 4.2 Constitutive equations for protein deposits -- 4.2.1. One-dimensional generalised Maxwell model -- 4.2.2. Three-dimensional visco-hyperelastic model -- 4.2.3. Parameter identification through inverse finite element method -- 4.2.4. Application of modelling approaches -- 5. Conclusion and Outlook. .