Effect Of Wheat Starch And Rheological Properties On The Quality Of Dumpling Skin

This paper use222kinds of wheat in our country’s10provinces as raw material, and unified milling them to wheat flour. First, we determinated the wheat samples’s moisture, ash, falling number, sedimentation value and other physical and chemical indicators, the starch properties of RVA (Rapid ViscosityAnalyser) parameters, damage starch content etc, the rheology properties of farinaceous feature, extension property etc, and the dumpling skin texture, sensory and other quality characteristics which made of the above samples of wheat, and analyzed the correlation between the starch and the rheological properties of the dumpling skin quality. And then select three kinds of wheat flour samples which are great differences in regions and quality, Use the method of Flour restructuring, make the flour to mixed powder which the starch content and type of starch added are different from the original flour. Explore the effect of the content of a single endogenous or exogenous starch to the dumpling skin quality. Finally use two methods measured by DSC and X-ray diffraction to study of the starch retrogradation mechanism. Paper’s main results are as follows:1.The correlation analysis of starch properties and dumpling skin quality showed that:RVA parameters of peak viscosity, minimum viscosity, final viscosity, setback, peak time and fresh dumpling skin’s firmness, sensory evaluation indexes except taste value, fresh dumpling skin colour were significant or highly significant positively correlated, and they also have significant or highly significant positive correlation with the firmness, resilience, colour of the frozen dumpling skin, raw dumpling skin uniformity and brightness, cooked dumpling skin apparent reaction, elasticity, chewiness and sensory scores. Breakdown, pasting temperature and fresh dumpling skin toughness, frozen dumpling skin’s toughness, chewiness, hardness were significantly negatively correlated. Damage starch content and toughness, hardness, chewiness, sensory quality of fresh and frozen dumpling skin, and fresh dumpling skin’s colour were significantly positively correlated. Starch content and fresh dumpling skin elasticity, viscosity, chewiness, taste and sensory scores were significantly positively correlated. And they have significantly negative correlation with the uniformity of skin of frozen raw dumplings, frozen cooked dumpling skin viscosity and hardness.2. The correlation analysis of the rheological properties and dumpling skin quality showed that: The degree of softening have the most indexes which were significant negatively correlated with fresh and frozen dumpling skin’s texture and sensory index, followed by the formation time, the farinograph quality number, stability time and water absorption, but they showed a significant positive correlation with the fresh and frozen dumpling skin quality. Extensograph area, extension resistance, the proportion of the maximum tensile and the quality of dumpling skin were significant positively correlated. Extensibility has highly significant positive correlation with the firmness of fresh and frozen dumpling skin. Alveogram has positive correlation with fresh and frozen dumpling skin’s part of the texture index and has no correlation with fresh dumpling skin sensory indicators.3. Wheat flour recombination experiments showed that:When making dumpling skin, different regions and different quality flour should select different content of starch addition. Wheat flour which have higher content and higher quality protein can added more starch, otherwise added a small amount of starch. Modified potato starch has more improvement degree than endogenous starch and cassava starch. When added starch dumpling skin’s enthalpy is smaller than the blank starch, To some extent, starch reduce the degree of retrogradation of the dumpling skin. With the adding of Starch, the starch molecules in the dumpling skin have a re-polymerization, and amylose-lipid complexes have no significant change occurs during the storage, so they have no significant decline in bite, amylopectin recrystallization gradually increasing is an important factor to the sensory quality of the dumpling skin.