Ultrahigh pressure promotes colorless bovine serum albumin-glucose conjugates generation

- Ultrahigh pressure (UP) at 240 and 360 MPa promotes glucose-BSA conjugate formation.
- UP-conjugation of glucose-BSA did not cause advanced pigment formation.
- UP-conjugation of glucose-BSA did not change the secondary structure of BSA.

Browning generation always limits the application of protein-carbohydrate conjugates. In the present study, we found that ultrahigh pressure can promote bovine serum albumin (BSA)-glucose conjugation without browning generation. BSA-glucose conjugates were fabricated at 120, 240 and 360 MPa for 4 h. The intermediate products, browning intensity, glucose concentration and secondary structure of conjugates were tested. Results suggested that BSA-glucose conjugates were generated at pressures of 240 and 360 MPa with significant increase of absorbance at 294 nm (Abs294) from 0.88 to 0.93 and 1.17, and marked consumption of glucose to 87 and 85%. While, insignificant change was found in browning (Abs420) or the secondary structure of BSA during conjugates formation with 40-42% α-helix, 5-10% β-sheet and 21-23% β-turns. Near no BSA-glucose conjugates were formed at lower pressure of 120 MPa. This study indicated that ultrahigh pressure is a potential method to generate colorless BSA-glucose conjugates.Industrial RelevanceThe color generation is a serious problem limiting the industrial application of protein-carbohydrate conjugates. There is nearly no report about inhibiting the color formation during fabricating protein-carbohydrate conjugates. Our study suggested an effective method to fabricate colorless BSA-glucose conjugates, which may provide potential improvement in food processing.