The Stickiness of Food

Stickiness is a difficult attribute to measure. Adhesion is characterised by the force of attraction between a material and a surface. This phenomenon occurs in several processes (such as baking, chocolate or powder production, bacterial adhesion to industrial plants), causing product losses and contamination. In this sense, parameters as surface energy and food composition play an essential role in adhesion study, being an essential field of understanding to optimise processes. A recent review approaches the adhesion fundamentals and their relation to food composition and surface properties. Moreover, it describes the tests usually applied to measure the adhesion of food on surfaces. Besides, this work shows that, regarding the literature, it is difficult to differentiate the adhesive from the cohesive forces. Food adhesion in different dryers and alternative to reduce the problem are discussed, considering that the deposition of dried material on supports and dryer walls causes low yields and operational and handling problems.