The measured growth of ice crystals provides other evidence for
the in-crumb redistribution of water in frozen bread. Initially, ice
crystals nucleate and grow from local freezable water in the gas
cells as well as inside the glutenestarch matrix. This process
appears to proceed within minutes, occurring at the time scales of
general DSC cooling scans and producing ice crystals with sizes of
nm (Chen et al., 2012). Further growth of these ice crystals demands
crumb water to redistribute regionally or even globally. Dynamically,
the water redistribution is accompanied by the recrystallization
of ice crystals, whereby large crystals develop on the melting of other small crystals (Petzold and Aguilera, 2009). Evidence exists
that the reorganization of crumb water is preferentially toward the
gas cells, in which ice crystals grow within hours into the sizes
observable under microscopes (Baier-Schenk et al., 2005a, 2005b;
Esselink et al., 2003). Our calorimetric analyses further showed that
build-up of bulk-sized ice crystals in frozen breadcrumb should
take days of storage. Onwards, the expansion of ice crystals slows
down even more (see Table 1). It is hypothesized that at prolonged
stages of frozen storage, the freezable water is essentially depleted
inside the crumb. The engendering and then redistribution ofwater
are constrained by the necessity of collapsing ice crystals, which
slows down the overall dynamics of water and ice crystals.