Food rheology: Elasticity

Food rheology: Elasticity
Many objective method for measurement of food quality involve measurement of some aspect of texture, such as hardness crispness or consistency.

Texture is related to the rheological properties of food, which determine how is responds when subject to forces such as cutting, shearing or pulling.

Rheological properties can be divided into three main categories. A food may exhibit elastic properties, viscous properties or plastic properties or a combination.

In reality, rheological properties of most foods arte extremely complex and they do not fit easily into one category.

Elasticity
Elasticity is a property of a solid and can be exampled by a rubber band or a coiled spring.

If a force or stress is applied, the material will deform (stretch or be compressed) in proportion to the amount of force applied, and when the force is removed, it will immediately return to its original position.

The force required to break the material is known as the fracture stress.

Some solids are more elastic than others; examples of very classic solids are spring and rubber bands.

Bread dough also has elastic properties, although its rheology is complex and includes viscous and plastic components as well.

All solid foods exhibit elastic properties to some degree.
Food rheology: Elasticity