Effects Of Temperature, Vacuum And Addition Timing And Mass Transfer On Permeation Of Flavor Substance In Egg White Gels

Since the marinated eggs are cooked before they are marinated,the dense gel network structure formed by egg white protein denaturation makes it very difficult to penetrate the flavor substances from the outside to the inside.The production process spend too much time,and it takes about 4 hours even if the method of industrial high temperature and high pressure is adopted.The content and the mass transfer coefficient of the flavor substances（sodium chloride,sucrose,glucose,citric acid,lactic acid）in the gels at different temperatures were studied.Simultaneously,the effects of gas solute and vacuum environment on the infiltration process in permeate solution were analyzed.The effect of sodium chloride and other four flavor substances on the infiltration process in egg white gels when the permeation sequence was different was studied.A preliminary exploration of the non-destructive detection of the penetration of egg white gel using low-field NMR technology was conducted.The results are as follows:1.The permeation and mass transfer coefficients of five flavor substances in egg white gel under different temperatures and different vacuum conditions were studied.Different flavor substances are influenced by temperature.The calculation of apparent activation energy of the diffusion process shows that the diffusion activity of glucose is affected most by temperature and the lactic acid is the smallest.After removing the gas solute from the infiltration solution,the permeation rates and mass transfer coefficients of sodium chloride,sucrose,and glucose in the egg white gel were all increased,while that of citric acid and lactic acid was not significant.It is shown that the gas solute in the penetrating solution has some hindrance to the penetration process of sodium chloride,sucrose and glucose.The vacuum had no significant effect on the penetration of the five flavors in the egg white gel（p>0.05）.2.The permeation and mass transfer coefficients of sodium chloride and other four flavors in egg white gels at the different time or in the same order were studied.When permeating together,sodium chloride significantly inhibited the penetration of the other four flavors（p<0.01）.Sucrose and glucose slightly inhibited the penetration of sodium chloride,while citric acid and lactic acid had a slight promotion effect.But the difference was not significant when sodium chloride alone penetrated（p>0.05）.On the whole,sodium chloride is less affected than other four flavors when penetrated together with other flavors.The advance penetration of sodium chloride promotes the penetration of the other four flavors,especially glucose（p<0.05）,which has little effect on citric acid and lactic acid（p>0.05）.The premature penetration of citric acid or lactic acid promotes the penetration of sodium chloride by increasing the mass transfer area,whereas sucrose or glucose are the opposite.3.Under the selected infiltration conditions,the natural logarithm of the mass transfer coefficient of the flavor substance in the egg white gel and the natural logarithm of the time have a good fitting effect.So the time can be used to predict the mass transfer coefficient of flavor substances under different conditions.4.The transverse relaxation time T₂ of egg white gel was measured by low field NMR.The correlation between the content of sodium chloride or sucrose in egg white gel and its T₂₂peak property was studied.The results show that there is a good correlation between the sodium chloride content and the peak start time and peak apex time,as well as between the sucrose content and peak end time and peak width.A preliminary judgement of the degree of penetration of sodium chloride in egg white gels can be made using low-field NMR techniques.In addition,quantitative analysis of the degree of penetration through low-field NMR techniques requires further research.