Enzymatic Extraction And The Study Of Characteristics Of Water-soluble Substances From Eggshell Membrane

With the increasing production and consumption of eggs every year the four million tons of eggshells were discarded, but the study of egg membrane has lagged behind. The wet weight of egg membrane (commonly known as Phoenix clothing) is about 1.02% of egg, egg membrane contains about 90% proteins, 3% liposomes and 2% carbohydrates. The study of the egg membrane is not only favorable for the rational use of resource, but also for the protection of the natural environment. Therefore the issue studied the applications and applies of the egg membrane systematically.1.The content of crude protein of egg membrane is high as 91.14%. Egg membrane is fibrous network structure, and is insoluble in water. The experiment made different protease to extract soluble substances in the egg membrane, the process is as follows: alkaline protease at 65℃, pH9.5, concentration of the substrate(S0) is 5.00g/100ml, concentration of the enzyme(E0) is 5.62×103U/100ml, the value of DH at 2h is 11.54%, TCA-NSI is about 48.80%. And the kinetic equation of alkaline protease at pH 9.5 and 65℃under the condition of the limited hydrolysis: R(Hydrolysis rate) = (1264.7E0–18.688S0) ? exp [-0.2352 ? (DH)], and DH = 4.2517×ln [1 + (297.584 E0/S0– 4.397) ? t].2.The study of freeze-dried products of the water-soluble substances which were extracted from was analyzed, the content of protein is more than 90%, the molecular weight of protein mainly between the 261Da and 2034Da. The content of essential amino acid is 40.40%. The absorbent, emulsifying and emulsion stability, foaming and foaming stability of water-soluble material of egg membrane water material are varying degrees of improvement.3.Different effects of enzymolysis water-soluble substances of egg membrane added to the flour, and studied the characteristics of the flour, RVA, the properties of rheological. The results showed that: with the same amounts of added water-soluble substances of wheat flour the dough formation time was as follows: water-soluble substances (DH=15.74%)> water-soluble substances (DH=16.59%)> water -soluble substances (DH=9.62%); When add the water-soluble substances (DH=15.74%) to flour for 3.0 percent points, the G 'and G " of the dough were 13720Pa and 6246Pa when swept to 0.1Hz,which were increased 52.3% and 7.2% more than the control.4.The experiments of bread showed that: Adding of the water-soluble substances proofed the fermentation time of the dough to be shorter than the control, can also improve the texture and quality of bread. Adding of 5% of water-soluble substances (DH = 15.74%) can increase more 13.6% of specific volume of the bread than the control. The score of sensory evaluation is 93, after 1 d of the storage, the score is 83. Based on the kinetic model we can derive the process of water-soluble substances (DH = 15.74%) :on the role of alkaline protease, T is 65℃, pH is 9.5, a functional equation for t and E0/S0 is t= 67.679×E0/S0-40.530.