| Buckwheat flour is a grain rich in protein,amino acids and other nutrients,often used as raw materials for food processing,but buckwheat contains a very small amount of gluten protein,which limits the application of buckwheat flour in the processing of flour products.In order to improve the utilization rate of buckwheat flour and improve the freezing quality of wet noodle products,his thesis uses buckwheat flour as the main raw material and hydroxypropyl and phosphate modified starch prepared in this laboratory as additives for the production of buckwheat dumplings.Based on the analysis of the effects of hydroxypropyl and phosphate modified starch on the gel properties of buckwheat flour,such as hydration,gelatinization and dynamic rheology,the preparation formula of buckwheat dumpling wrappers was optimized,and the quality changes of buckwheat dumplings wrappers during frozen storage were explored.The main findings are as follows:1.Add 0%,1%,3%,5%,7% and 9% hydroxypropyl and phosphate modified starch to buckwheat flour to study the physical and chemical properties of mixed powder.The results showed that with the increase of hydroxypropyl and phosphate modified starch addition,the water solubility index and expansion potential of buckwheat flour first increased and then decreased(P<0.05),and the water absorption index increased.The peak viscosity,final viscosity and rejuvenation value showed a trend of first increasing and then decreasing,and the elastic modulus G’ and viscous modulus G" values of buckwheat flour gel increased first and then decreased.The hardness of buckwheat flour gel is constantly reduced,and the elasticity and cohesion are enhanced;With the increase of the number of freeze-thaw cycles,the freeze-thaw water precipitation rate of buckwheat flour continued to increase,and the water precipitation rate decreased first and then increased with the addition of two modified starches in a single cycle.When the addition amount of hydroxypropyl starch was 1%～3%,and the amount of phosphate starch was 1%～5%,the content of bound water in buckwheat flour gel gradually increased,the free water content decreased,and the gel network was gradually uniform and tight.2.Taking buckwheat flour as the main raw material,taking the amount of water addition,hydroxypropyl modified starch addition and phosphate ester modified starch addition as three factors,the effects of each factor on the transmittance rate,water loss rate after quick freezing,freezing cracking rate and texture characteristics of buckwheat dumpling soup were analyzed,and the orthogonal test determined that when the water addition amount was 58%,the hydroxypropyl modified starch addition amount was 3%,and the phosphate ester modified starch addition amount was 5%,the quality of buckwheat dumpling wrappers was better,and the soup transmittance was 78.95%;The freeze-cracking rate was1.67%;The water loss rate after quick freezing was 0.76%.3.The results showed that with the extension of freezing time,the moisture content in the dumpling wrappers of the control group and the formula group continued to decrease,and the water loss rate and freezeable water content increased(P<0.05),but the moisture content of the dumpling wrappers in the formula group was higher than that of the control group,and the water loss rate and freezeable water content were lower.The hardness of dumpling wrappers increased after cooking,the elasticity and cohesion decreased,the water absorption rate during cooking continued to decrease,and the cooking loss increased,and the trend of the control group was similar,but the change range was higher than that in the formula group.The firmness,elasticity and surface state of buckwheat dumplings in both groups deteriorated,but the formula group had higher sensory scores,more water content,and a more complete surface structure state. |
PDF Full Text Request