Sufu is a delicious traditional Chinese food, mainly produced by fermentation using soybeans as raw material. Egg white is rich in protein and is theoretically an excellent material for sufu processing, however there are few reports on egg-white sufu (EWS) currently, and no such product is available on the market. In this paper, a novel sufu was processed with egg white as main material, and the formation mechanism of its unique quality was explored by monitoring the dynamic changes in the pre-fermentation and post-fermentation stages. The dynamic change curve of protease activity showed an "S" shape, with a peak of 32.33 U/mL on the 4th day of pre-fermentation stage. After a 4-day pre-fermentation and 90-day post-fermentation, most of the proteins in the EWS had been hydrolyzed, and the sufu was moderately soft and delicate in texture, with a hardness of 950.3 g and a total free amino acid content of 19.863 mg/g. SEM and SDS-PAGE detections suggested that the proteins in EWS had been extensively degraded, which led to the formation of its unique texture and flavor. The EWS was slightly better than soybean sufu in terms of texture, fragrance and mouthfeel, with flavor compounds mainly composed of aldehydes and alcohols, resulting in a slightly higher total sensory evaluation score.
