The effect of proteolytic enzymes on the thermostability of egg‐white

The effect of proteolytic enzyme preparations such as Proteopol PB (bacterial origin), ficin, and pancreatin on the thermostability of egg-white proteins during pasteurization was investigated. Proteolytic activities of each enzyme were measured at three different doses which were calculated by the ANSON method. The degree of white protein degradation was evaluated by the determination of amino-nitrogen. Effectiveness in reducing the coagulation of egg-white proteins varied, depending on the type and dose of enzyme used. Proteopol PB showed only little effect, ficin demonstrated the best anticoagulation properties at the lowest dose, while for pancreatin the middle dose proved to be the most effective. It was concluded that moderate proteolysis is useful for improving the thermostability of egg-white proteins during pasteurization. Total bacterial counts increased considerably after incubation of egg-white with enzyme preparations, but after pasteurization the number of bacteria decreased to levels which were compatible with bacteriological standards for egg-white products.