Physical properties

Physical properties are characteristics of substances that can be observed or measured without involving a chemical change, such as density, mechanical properties, optical properties, thermal behavior, and electrical properties. In food science, they include texture, viscosity, color, and the electrical properties of foods relating to their ability to conduct electricity, such as capacitance, dielectric behaviour, conductivity or resistance, and electrostatic interactions. Electrical resistance, for instance, generates heat as current passes, a principle exploited in ohmic heating. Measuring physical properties underpins process design, equipment selection, and quality control, since these attributes determine how foods behave during processing and how consumers perceive them.