The Research On Functional Characteristics Of Salted Duck Egg White And The Application Of Its Hydrolysates

Salted duck is a traditional Chinese food which is much popular, and salted duckegg yolk is acclaimed. Salted duck egg white because of the high salinity and poortaste often becomes the table discarded.In this thesis, I study on the salted duck egg white enzymatic hydrolysisconditions, and optimized the enzymatic hydrolysis conditions. Papain, trypsin,neutral protease, and flavor protease were used to enzymolysis the salted duck eggwhite, and ultimately trypsin was the most optimal hydrolysis enzymes of salted duckegg white. Then I study on the enzymatic hydrolysis time, reaction temperature,enzyme dosage and pH value effected on the enzymatic hydrolysis degree. And onthese basis, I got the regression model, then used the method of mathematical analysisto analyse the regression model, got the optimum conditions were the reactiontemperature of46℃, the amount of enzyme to3500U/g, pH value of8, the degreeof hydrolysis measured was25.36%on the conditions of the experimental.The foaming and emulsifying features of the salted duck egg white wereresearched and analysis systematically. Respectively investigated the effects of theheating temperature, heating time, protein concentration and pH value. Theexperimental results showed that the salted duck egg protein concentration of7%, thepH value of5under the conditions of the heating treatment at50℃thermostaticwater bath20min, then used the recycled water to rapidly cooled the salted duck eggprotein to room temperature, and homogenate it5min can get the highest foaming andfoam stability. Study on the emulsifiability and emulsion stability, when theconditions of the the salted duck egg white concentration of6%, pH value of5underthe conditions of the heating treatment at30℃thermostatic water bath20min, removed it1min later homogenate can get the best emulsion stability.In order to improve the functional characteristics of the salted duck egg white, Ichoose the glucose, lactose, and maltodextrin as the sugar donor. Experimental resultsshowed that the increasing in the number of days with the Maillard reaction, the saltedduck egg white were improved in the various aspects. Comparative analysis of threedifferent sugar donor, glucose as monosaccharides was the best sugar donor of thesalted duck egg white modified, followed by the maltodextrin, the effect of lactosewas general.In this thesis, the salted duck egg white was used as a nitrogen source in enteralnutrition, not only took full advantage of salted duck egg white which is ahigh-quality protein, also increased its use value, and reduced the impact on theenvironment of the large number of abandoned salted duck egg white. After the studyof the functional properties of the salted duck egg white, used it to prepare the enteralnutrition.The factors detected by animal experiments show that, the enteral nutrition withthe protein and peptide of salted egg can provide sufficient nutrients to maintain thebody’s nutritional status and improve the function of the body’s immune response,effectively control the production of inflammatory cytokine, protection the barrierfunction of the intestinal mucosa. Enteral Nutrition prices are generally expensive, thechoice of salted duck egg white resources will reduce the cost of enteral nutritionaland alleviate the patient’s hospitalization expenses.