Study On Quality Change And Shelf Life Prediction Of Quick-frozen Rice Dumpling During Storage And Distribution

Rice dumpling originated from the Song Dynasty and was a traditional Chinese holiday food.Accompanied by the improvement of quick-freezing technology.It has now broken the traditional model and gradually became a fast-frozen food that popularizes daily life.It has become the second-largest sales food in quick-freezing.In this paper,the effect of different freezing temperature and temperature fluctuation on the quality of quick-frozen dumplings was studied by using quick-frozen dumplings.The characteristics of various quality indicators during the storage of quick-frozen dumplings were determined by low-frequency-NMR and RVA.SEM and other means to fundamentally explore the fundamental internal mechanism of the quality change of the frozen dumplings under different freezing temperature and temperature fluctuation conditions,and seek the optimal storage temperature.Based on the quality values and sensory scores of each stage under different freezing temperature and temperature fluctuation conditions,combined with BP neural network technology to predict the shelf life of quick-frozen dumplings under different freezing temperature and temperature fluctuation conditions,and study the shelf life.And the development of early warning systems in the process of safety monitoring and cold chain circulation provides specific data support.In order to provide a certain theoretical reference for the quality maintenance of the frozen dumpling during the frozen period.The main conclusions are as follows:(1)By studying the changes of moisture content,peroxide value,acid value and texture characteristics of quick-frozen dumplings under the three constant temperature frozen conditions of-5,-15,and-25?,combined with low-frequency-NMR,RVA,SEM,and rheometers.The quality change law of the frozen dumplings under different freezing temperatures and its internal fundamental mechanism are discussed.The results showed that different freezing temperatures had significant effects on the quality of quick-frozen dumplings(P<0.05).With the extension of freezing time,the moisture content of quick-frozen dumplings was reduced.The oxidation of filling oils and the hardness of texture properties Chewing sex has increased.And the higher the freezing temperature,the greater the quality change.The large ice crystals generated by the high freezing temperature acting on the water state cause damage to the glutinous rice starch,which causes the quality of the quick-frozen dumplings to decrease,and the freezing temperature condition of-25? can effectively delay the deterioration of the quality of the quick-frozen dumplings.(2)A comparative study on the changes of moisture content,peroxide value,acid value and texture characteristics of quick-frozen dumplings under temperature fluctuation storage conditions of-13? to-23? and under constant temperature storage conditions of-18? Low frequency-nuclear magnetic resonance,RVA,SEM and other means.Fundamentally,the influence of temperature fluctuation on the quality of quick-frozen dumplings and its internal change mechanism were discussed.The results showed that with the prolongation of storage time,the moisture content of the frozen dumplings was reduced,and the oxidation of the filling oil,the hardness of the texture characteristics and the chewiness increased.However,the temperature fluctuation of the quality of the frozen dumplings was significantly higher than that of the constant temperature storage conditions(P<0.05).Due to the influence of temperature fluctuations,the change of its water state is obviously greater than that of the constant temperature storage environment,and the formation of large ice crystals is more serious,so the influence on the quality of quick-frozen dumplings is also greater.(3)Based on the first two parts and BP neural network technology,a shelf life prediction model was established to predict the shelf life of quick-frozen dumplings.The results show that the comparison between the predicted results and the actual results shows that the maximum relative error is 1.18%,the minimum relative error is 0.04%,and the prediction results are more accurate.For the quality index as the input layer,the relative error between the storage time and the temperature or the remaining shelf life predicted by the effective accumulated temperature is large,which is mainly due to the numerical measurement of the quality index itself,which will cause certain error fluctuations and have certain instability.Sex,while the time temperature is recorded as a fixed value.Has a strong credibility.Therefore,it is recommended to use a time temperature recorder for the cold chain link of the quick-frozen dumplings,so that the predicted shelf life reliability is more accurate.