Testing Products with a Crust, Skin or Multilayers

Products with a crust, skin or multilayers bring textural variety to a product. The breaking of the skin of an apple when bitten into or the biting through the layers of the perfect pastry product brings a textural sensation that is highly desirable and anticipated. Failure to notice a difference in the layers of such products brings disappointment.

The collection of detail of a thin, brittle, laminated or multi-phased structure is best performed with a small diameter probe or thin, sharp fixture. A larger probe such as a platen, cylinder or sphere will give bulk compressive properties but will not resolve the properties of each layer. It is beneficial to penetrate the sample slowly in most cases to give a larger time gap between fracture or puncture events so they can be more easily identified.