Abstract:Eggs were added to rice vinegar emulsion (egg vinegar quality ratio 1:1, 1:2, 1:3, 1:4), to prepare functional vinegar-egg emulsion. The degree of egg protein hydrolysis, protein molecular weight distribution, protein particle size, protein secondary structure, and denaturation temperature were analyzed during the hydrolysis. Results showed that the ratio of egg to vinegar 1:4, the degree of hydrolysis reached a maximum of 12.82%±0.51% (p<0.05) after soaking for 72 h. Lysozyme, yolk high-phosphorus protein, IgY and low-density lipoprotein were not easy to decompose in rice vinegar. But the degradation of egg transferrin, ovalbumin, egg mucin and subunit, and high-density lipoprotein were very obvious. Treated by the rice vinegar, the α-helix and β-sheet of the egg protein decreased, and the β-turn increased, showing that the secondary structure of the protein was disordered. And the protein particle size of egg was lowered, the particle size distribution changed from a single peak to a double peak or even a triple peak. Compared to the egg liquid, the heat denaturation temperature of the vinegar-egg emulsion was increased, it meant that the thermal stability was increased. In summary, eggs hydrolyzed by rice vinegar produced a large number of peptides and small molecule oligopeptides, the structure and properties of proteins were changed. This study provides a reference for the study of quality characteristics and products of vinegar-egg emulsion.
