Abstract: The methods for separating eggshell from its inner-membrane, which have been mentioned in some literatures before have been compared, and certain improvements of the separating technology have been made. It has been found out that if one- step alkali treatment was only used during separation, any acid needn’t be used, and the separation technology could be simplified, the separation was very thorough. Meanwhile, the main factors closely related with the results of keratin hydrolysis, including extracting temperature, alkali concentration and ratio of solid/liquid, have respectively been studied, then based on this, the orthogonal test has been conducted and optimal combination of the three has been obtained, under 85℃, 5.2% of alkali used, and 1:16 of solid/liquid, the extracting rate of keratin from eggshell inner-membrane was 48.6% under this experiment. The keratin in hydrolysis liquid could be purified by dialysis, dehydration by polyethylene glycol, and vacuum drying.

Key words: eggshell membrane, keratin, hydrolyze, extracting