Effect of mechanically damaged starch from wheat flour on the quality of frozen dough and steamed bread.

The influence of damaged starch (DS) on the quality of frozen dough and steamed bread were investigated. Characterization of the farinographical properties showed that DS levels affected water absorption, development, weakness, falling number and gluten index. Flour viscosity profiles indicated that pasting temperatures increased, but peak viscosity, low viscosity, breakdown, final viscosity and setback increased and then decreased with increasing amounts of DS. Compared to leavened dough, unleavened dough had significantly higher peak times, of T21 and T22, and was also affected by DS concentration. Steamed bread had a higher specific volume, relatively lower hardness, exhibited more whiteness, and a higher degree of gumminess and chewiness with higher DS levels. We compared two methods of making steamed bread and assessed the quality of the product. We found that an appropriate DS content improved the quality of frozen dough and steamed bread. This study provides the basis for future development and improvements to methods for making frozen dough products.

Extraction, characterization and spontaneous emulsifying properties of pectin from sugar beet pulp.

The effects of organic acid extractants on the yield and characteristics of pectin from sugar beet pulp were investigated with citric acid, malic acid and lactic acid at different pH (1.5 and 2.0) and time (1 h and 2 h). The results demonstrated that the yields of pectins were directly correlated with the decrease of pH and reaction time, and the optimum yield of 17.2% was obtained at pH 1.5 and 2 h. Furthermore, the acid type also affected the physicochemical characteristics of pectin, especially on the esterification degree (42-71), galacturonic acid content (60.2-77.8%), emulsion activity (35.2-40.1%) and emulsion stability (62.1-79.4%), and a relatively single pectin mainly consisted of homogalacturonan could be obtained under a suitable reaction condition, which was an excellent crude material for the production of emulsion activity.