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The role of starch gelatinisation temperature in retermining loaf volume studied using annealed starch.
S. Cobbold, A. A. TSIAMI, and J. D. Schofield. The University of Reading, Department of Food Science
and Technology, Reading RG6 6AP, UK.
The baking performance of wheat flour is considered to be related
primarily to flour protein quality and quantity, although during baking there are other mechanisms that may
influence the final loaf volume. For example, the gelatinisation of starch produces a major rheological
transition in dough during baking, and the influence of starch gelatinisation temperature on bread making
performance was investigated in this research. Annealing was used to modify starch gelatinisation
temperature. Two temperatures, 25° and 45°C, were used for annealing. Effects on gelatinisation
characteristics were measured by DSC, Rapid Visco Analysis (RVA) and small deformation rheology. The
gelatinisation temperature of the starch that was annealed at 45°C was increased by 8° as determined by
DSC. The onset of the development of viscosity during heating in the RVA was also delayed as a result of
annealing. Starch (annealed and native), commercial gluten and water-solubles from cv. Hereward
flour were used to prepare reconstituted flours, the baking performances of which were then determined in a
micro-baking test. The presence of starch annealed at 45°C lead to increased loaf volumes, which correlated
with the increase in gelatinisation temperature. The results imply that variation in starch gelatinisation
temperature may contribute to variation in bread making performance in wheat.
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