Effects Of Freezing Storage Temperature On Gluten Protein Of Non-fermented Dough And Quality Of Frozen Dumpling Skin

Frozen flour products have developed rapidly in recent years because they meet people's requirements of convenient food processing and saving time and effort.However,in the production,transportation,storage and secondary processing of frozen flour products,there are many problems that fresh flour products do not appear,which affect the quality of frozen flour products and limit the development of frozen food in the market.In this paper,the effect of temperature on gluten and frozen flour products during freezing storage of non-fermented dough was studied from the perspective of temperature,aiming at exploring the mechanism of deterioration of frozen flour products caused by freezing storage temperature.The main research contents are as follows:(1)Study on the effects of different freezing storage temperatures on the functional properties of glutenThe functional properties of gluten have a direct impact on the sensory quality of products,so the effects of different freezing storage temperatures on gluten yield,soluble protein content,water and oil holding capacity,foaming and foam stability,emulsification and emulsification stability,and rheological properties were studied.It was found that the yield,emulsification and emulsification stability of gluten protein were not greatly affected by different freezing storage temperatures.The soluble protein content and water holding capacity decreased with the decrease of freezing storage temperature.The oil holding capacity,foaming ability and foam stability were greatly affected by freezing storage time.The storage modulus and loss modulus of gluten decreased with the decrease of freezing storage temperature.(2)Study on the effects of different freezing storage temperatures on water distribution and microstructure of gluten proteinThe deterioration of gluten during freezing is closely related to the state of moisture in gluten.Therefore,the distribution,content and migration of moisture in gluten and its influence on gluten network were studied by means of differential scanning calorimeter,scanning electron microscope and low-field nuclear magnetic resonance instrument.It was found that the freezable water content and water mobility of gluten were relatively low at-12 ?,and the skeleton of frozen gluten stored at-12 ? was more complete and smooth under electron microscope.(3)Study on the effects of different freezing storage temperatures on the molecular structure of gluten proteinThe study on the molecular structure of gluten protein at different freezing temperatures helps us to understand the fundamental cause of the functional changes of gluten protein during the freezing process,and helps us to optimize the protein from the aspect of molecular structure and improve the quality of frozen dough products.The secondary structure of gluten protein,contents of sulfhydryl group and disulfide bond,surface hydrophobicity and molecular weight changes due to freezing temperature were studied.It was found that at low freezing storage temperature,more ?-helix structure expanded,resulting in a decrease in ?-helix structure content,disulfide bond content decreased with the extension of storage time,free sulfhydryl group showed an opposite trend,different freezing storage temperature has no obvious effect on the molecular weight of gluten protein.(4)Study on the effects of different freezing storage temperatures on the quality of frozen dumpling skinFinally,the effect of different freezing temperature on cooking characteristics,texture characteristics,color and freeze-crack rate of dumpling skin was studied.It was found that higher freezing temperature would lead to higher freeze-crack rate,and the texture properties of frozen dumpling skin at-12 ? were closest to those of fresh dumpling skin.By studying the effects of different freezing temperatures on gluten and frozen flour products,we found that different freezing temperatures will lead to different changes in the molecular structure of gluten protein,so the functional characteristics of gluten protein are affected to different degrees,and then affect the quality of flour products.It is very important to study the fundamental changes of gluten protein in order to put forward a more reasonable and improved technology of frozen dough production.Therefore,this paper fundamentally seeks the mechanism of the effect of freezing temperature on product quality,provides a new method to solve the problems in frozen flour products,and provides a new idea and theoretical basis for production research.