The effects of aging (storage) on the expansion of chou, the change in visual shape of chou paste (CP) during baking observed by a modified time-lapse photographic analysis (TLPA) and its rheological properties were examined before and during baking. The TLPA profile of CP was divided into the four stages of loosing, expanding, fixing, and drying. Chou products from the stored chou paste (SCP) demonstrated poor expansion and a less rugged surface than those from non-aged control CP (CCP). Values for the storage modulus (
G′) and loss modulus (
G″) of SCP were smaller and the hysteresis loop for the flow curve of SCP was larger than the values for CCP. The
G′ value for SCP was lower than that for CCP below 40°C, but this value was slightly higher than that for CCP between 57°C and 80°C. Above 83°C, no difference was found in
G′ for both CPs. When dextrin was added to a model chou paste containing starch instead of wheat flour, the expansion of the products was reduced, and the values for
G′ and
G″ of CP decreased with increasing dextrin concentration. These results indicate that the expansion of chou was impeded by storage which induced the production of low-molecular-weight starch substances in CP by enzymatic degradation.
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