On the other hand,
like fresh bread, the frozen bread also featured dual transitions,
marked I and II, for the melting of crumb-borne ice. Such dual
transitions have previously been shown to originate in the special
pore microstructure of breadcrumb that results in two sizedistributions
of ice crystals (Chen et al., 2012): large ice crystals
build up in large pores such as gas cells and small ice crystals are
confined mainly inside the gluten-starch matrix. Melting of the two
distributions of ice crystals thus contribute to the two endothermic
events (I and II). Essentially, the dual ice-melting endotherms are
a calorimetric signature of breadcrumb porosity. The similarity
between frozen and fresh bread suggests that the fundamental
pore geometries are largely preserved even over a prolonged
storage of w4 months.