Bread Staling: Molecular Basis and Control

Abstract

The molecular basis of staling is examined by reviewing what is known about the components of wheat flour, factors that affect staling rate, and the various mechanisms that have been proposed. The conclusion reached is that bread staling is a complex phenomenon in which multiple mechanisms operate. Polymer crystallizations with the formation of supermolecular structures are certainly involved. The most plausible hypothesis is that retrogradation of amylopectin occurs, and because water molecules are incorporated into the crystallites, the distribution of water is shifted from gluten to starch/amylopectin, thereby changing the nature of the gluten network. The role of additives may be to change the nature of starch protein molecules, to function as plasticizers, and/or to retard the redistribution of water between components. Nothing more definite can be concluded at this time.

Storage studies of bread prepared by incorporation of the banana pseudo-stem flour and the composite breads containing hydrocolloids

“…Water also influenced the retrogradation rate of a wheat-starch-based food system (Zeleznak & Hoseney, 1986). Water molecules are bonded into the starch/amylopectin and delayed the occurrence of amylopectin retrogradation (Gray & BeMiller, 2003).…”

Multilevel Structure of Wheat Starch and Its Relationship to Noodle Eating Qualities

“…It has been widely investigated that the firming of the bread crumbs during aging is mainly attributed to amylopectin retrogradation, particularly in the double helical structures and crystalline regions (Schoch 1942;Kulp and Lorenz 1981;Gray and Bemiller 2003). For noodles it is suggested that the crystalline structure could have an impact on noodle quality through 2 different processes: (a) dough making and (b) retrogradation after cooking.…”

Influence of germination time of brown rice in relation to flour and gluten free bread quality

“…This practice produces changes in the rheological properties of the batter, modifying dough handling, besides an improvement of crumb texture, increase of gas production during fermentation and retard bread staling (Charoenthaikij et al 2010b;Watanabe et al 2004). The late benefit likely related to the alfa-amylase action forming low molecular weight dextrin that could inhibit amylopectin retrogradation (Gray and Bemiller 2003). In addition, germination could produce an excessive liquefaction and dextrinisation of starch granule, producing 'wet sticky crumb' (Hallen et al 2004), because of that it is necessary to define the right germination time for optimizing flour breadmaking features.…”