Study On New Processing Technology Of High Quality Preserved Eggs

This dissertation studied the influence factors of egg white protein gel strength in the condition of sodium hydroxide and the variation of various physical and chemical characteristics during the processing. On the basis of these studies, we got the final NaOH gradient concentration of preserved egg processing technic. Finally, some physical and chemical indicators of safety preserved eggs were analyzed and detected. The main contents, results and conclusions in this dissertation are summarized as follows:1. The influence factors of egg white protein gel strength in the condition of sodium hydroxideBy egg white protein gel simulation outside the eggs, studied the influence factors of egg white protein gel strength in the condition of sodium hydroxide. The results showed that:NaOH concentration affect obviously the strength of egg white protein gel. Temperature have large impact on the speed of NaOH affecting on the egg white protein. Among the six kinds of metal salts additives, copper sulfate has the best effect to improve the gel strength of egg white protein. Among the five kinds of sugar additives, xanthan gum has the best effect to improve the gel strength of egg white protein. Among the three kinds of stabilizers and coagulant additives, propanediol has the best effect to improve the gel strength of egg white protein.2. The variation of physical and chemical characteristic of preserved eggs in the curing processUsing the traditional copper for pidan processing, didn’t add tea and other substances. According to a certain time interval, sampled and analysed. To research the change of physical and chemical characteristics during the processing. The results show that:alkalinity of curing liquid presents a declining curve; the pH value and free alkalinity of albumen increase rapidly at first and decrease gradually, then slowly increase again; the pH value and free alkalinity of yolk show an increasing trend; hardness of albumen presents an upward trend overall; flexibility, chewing and cohesion of albumen all increase firstly, then decrease slightly, and finally remain stable.3. The processing technic of safety and high quality preserved eggs in concentration of sodium hydroxide gradientFirstly, through finding the best NaOH concentration in veraison, NaOH concentration gradient orthogonal experiments, the method of high alkali and high temperature, it determined the initial processing technic. Then, to improve the experimental and verification experiment, it got the final NaOH gradient concentration method of preserved egg processing.4. The analysis of the physical and chemical indicators of preserved eggsAnalyzed and detected some physical and chemical indicators of security preserved eggs prepared by new concentration gradient of NaOH processing, and compared with boiled duck eggs and the preserved eggs of copper method. The results show that:The total alkalinity, pH, free alkalinity and copper content of security preserved egg white and yolk were significantly lower than the preserved eggs of copper method. These were conducive to reduce the alkaline taste and pungency of the preserved eggs, to increase its palatability and reduce the hazards of heavy metal elements, and to improve the quality of the product.