Analysis about the reason of the white edge of frozen dumpling after cooking

The phenomenon of the white edge 's frozen dumplings after cooking was the common quality problem of the industry.In order to explore the white reason and improve the edible quality of quick-frozen dumplings, this paper took the white edge 's frozen dumplings as our research target, which compared with the normal frozen dumplings. The content of moisture, the gelatinization of starch, the characteristics of texture, the eating quality and so on were researched by using SEM, colorimeter, etc.The results showed that, the moisture content and gelatinization degree of the white edge's frozen dumplings' skin were lower than the frozen dumplings ' skin which was not white (p < 0.01) . The moisture content and degree of gelatinization of the white edge's frozen dumplings' skin was significantly lower than the edge of the frozen dumplings' skin which was not white.After using Matlab to process the SEM image, the pore area of the white dumplings' skin was the largest and the degree of starch gelatinization was the highest.Followed by white dumpling skin, the pore area of raw dumplings' skin was minimum, starch was in the state of not gelatinized.Under the same electron microscope multiples and photo resolution, the microstructure of the white edge's frozen dumplings' skin had starch particles which obviously not entirely gelatinized. From the aspect of quality evaluation, it was found that the edible quality of the white edge's frozen dumplings was far worse than not white edges of a boiled dumpling quality. The white phenomenon of cooked frozen dumplings' skin may be due to the low moisture content, and not entirely gelatinized starch after cooking.