Abstract:Bird’s nest is a traditional nourishing food with rich nutritional value, however, there are few reports on its digestive characteristics. The gastrointestinal digestion of stewed bird’s nest was simulated through in vitro experiments in this research. The results showed that the solubility of protein, total sugar acid after the digestion of stewed bird’s nest increased from 13.85% to 47.23%, from 7.49% to 39.02%, and from 18.69% to 44.24%, respectively. For sialic acid, 17.41% existed in free form, 11.85% bound to glycan and 14.98% bound to protein. The degree of hydrolysis of bird’s nest protein was 11.54%, and 50% of the peptides were oligopeptides. Monosaccharide composition analysis showed that the solubility of O-type glycoprotein was lower than that of N-type glycoprotein. Glycoprotein staining showed that glycoproteins were hydrolyzed into several bands between 3.7×104~1.5×105, and the glycochain was tightly bound to the protein. The secondary structure of undissolved proteins during digestion was mainly β-fold and α-helix. The changes of chemical composition of the bird's nest during digestion process was comprehensively studied in this work, which could provide theoretical support for further development of new bird's nest products with high gastrointestinal digestion characteristics.
