40 The mechanics of cellular cereal products.

Micha Peleg. Univ. of Massachusetts, Amherst.

Bakery products like breads and cakes, puffed cereals and extruded snacks, all have a cellular structure which governs their deformability pattern. If the cells walls are not brittle the structure usually has an elastic compressibility range. Under higher deformation elasticity can be lost, to a variable degree, due to cell walls buckling or rupture. When all or most of the walls collapse, the resistance to deformation is primarily offered by the compacted walls material. The result is a compressive sigmoid stress-strain relationship whose exact shape depends on whether the cells are open or closed, the cell walls collapse pattern and the specimen.