Research Process Of Liquid Nitrogen Frozen Dumplings

In order to improve the quality of dumplings and explore the role of liquid nitrogen on regulating food quality,an experiment was conducted with dumplings as the research object,which was made of dough,meat and stuffing water.However,there were some differences in the water content,enthalpy and freezing rate in each component,therefore,and the dumpling-cracking rate itself was a complex manifestation,which in the meantime could also be affected by the quality of flour,ratio of raw materials and specifications etc.This study was aimed at understanding how the amount of water when kneading dough,the incubation time of the finished dough,the dumpling wrapper and meat stuffing ratio and the immersion time of dumplings in liquid nitrogen pool affected the cracking rate of the dumplings,which took pork,mushrooms and soy protein as the main raw material of dumpling stuffing.The result showed that the water amount of the flour had great influence on the gluten network formation of dumpling wrapper and dough processing characteristics.The dumplings from the same batch in the process of quick freezing tunnel method had far lower cracking rate than the liquid nitrogen freezing technology.Compared with freeze tunnel,being frozen in liquid nitrogen would have shorter freezing time and faster shaping time.Regardless of the water amount in dough,according to the water distillation principle,outer layer of wrapper would appear to be white powder layer,and the dumpling wrapper whiteness improved significantly(P<0.05)when frozen in liquid nitrogen(fresh 83;frozen 85;liquid nitrogen 88).Liquid nitrogen freezing method for food preservation and quality improvement is better than quick freezing tunnel method.Through the construction of the relationship between dough sensory and texture characteristics,the dough elasticity in industrial production could be expressed by texture determination,rather than relying on the subjective factors from experienced workers.Also in order to reduce or eliminate the dumpling-cracking rate,it could not only control the selection of the flour,the water addition and the dumpling wrapper and meat-stuffing ratio etc.,but also control the selection of additives(single and combined).Through market research,with the increase in air separation plants,liquid nitrogen production cost had been slashed,and the use of liquid nitrogen in the industrialized production of food would have good prospects.The result showed that there were some effects at different degree on dumpling cracking rate for the 4factors above.The dumplings would have relatively low cracking rate(37%)and highquality(77.6)under mass ratio of water to flour was 56:100,less than 10 min incubation time of finished dough,1:1.3 weight ratio of dumpling wrapper and meat stuffing and immersing in nitrogen pool for 40 s immediately after the dumplings were done.The study provides a theoretical reference for the application of liquid nitrogen on food process.Through the frost crack rate can effectively reduce the dumplings in the industrial production and use of additives,intends to look for in liquid nitrogen quick-freezing process under the condition of proper adding dose.Through a large number of trials,found that the traditional additive amount has not apply liquid nitrogen quick-freezing process.Glycerin is added in the experiment has meat can effectively reduce the dumpling frost crack occur in the process of quick freezing,but because of its sweet taste characteristics,and add dose.therefore,it does not apply to liquid nitrogen frozen sweet food.