Effects of ultrasound on the thermal and structural characteristics of proteins in reconstituted whey protein concentrate.
The sonication-induced changes in the structural and thermal properties of proteins in reconstituted whey protein concentrate (WPC) solutions were examined. Differential scanning calorimetry, UV-vis, fluorescence and circular dichroism spectroscopic techniques were used to determine the thermal properties of proteins, measure thiol groups and monitor changes to protein hydrophobicity and secondary structure, respectively. The enthalpy of denaturation decreased when WPC solutions were sonicated for up to 5 min. Prolonged sonication increased the enthalpy of denaturation due to protein aggregation. Sonication did not alter the thiol content but resulted in minor changes to the secondary structure and hydrophobicity of the protein. Overall, the sonication process had little effect on the structure of proteins in WPC solutions which is critical to preserving functional properties during the ultrasonic processing of whey protein based dairy products.
School of Chemistry, University of Melbourne, VIC 3010, Australia.
Jayani
J
Chandrapala
Bogdan
B
Zisu
Martin
M
Palmer
Sandra
S
Kentish
Muthupandian
M
Ashokkumar
D008894:Milk Proteins / Q000737:chemistry* / Q000528:radiation effects* / Q000648:ultrastructure; D011487:Protein Conformation / Q000528:radiation effects; D011829:Radiation Dosage; D013010:Sonication / Q000379:methods*; D013696:Temperature; D000067816:Whey Proteins
D008894:Milk Proteins; D000067816:Whey Proteins