Several theories have been put forward regarding the factors involved in the firming of bread crumb, or staling. Despite much research on the subject, the mechanism of bread staling remains under debate. Zobel (1996, ref. 1) proposed a comprehensive staling model based only on known starch molecular conformations and properties. In zobel's model gluten is relatively inert to changes over time and appears to have only minor effects on staling. Martin and Hoseney (1991, ref. 2) had previously proposedthe divergent hypothesis that bread firming may be a result of hydrogen bond interaction between gelatinised starch and gluten. Certain alpha-amylases inhibit staling of bread. Martin and hoseney proposed that the dextrins formed during hydrolysis interfere with the starch / gluten interaction and thereby retard the staling process. Gerrard et al. (1997, ref. 3) later presented evidence that dextrins are not the direct cause of antistaling, but merely act as a marker. The aim of the present study was to determine if the rate of staling is comparable in starch and wheat breads and how various amylases influence texture and specific molecular events in the starch.
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