Examining Committee  
Dr. Yoshi Mine, Chair  
Dr. Iris Joye, Advisor  
Dr. Michael Rogers, Advisory Committee Member   
Dr. Massimo Marcone, Department Member  
  
TITLE: EFFECT OF TEMPERATURE-RELATIVE HUMIDITY ON THE PHYSICOCHEMICAL AND FUNCTIONAL PROPERTIES OF POWDERED EGG WHITE PROTEIN  
  
ABSTRACT:  
The relationship between physicochemical and functional properties of egg white  protein (EWP) powders subjected to various two-week temperature-relative humidity (T-RH) treatments was investigated. The most severely treated sample (i.e., EWP powder incubated at 70℃ and 70% RH had the lowest protein solubility, a decrease in accessible thiol and amino group content relative to the other samples. Protein aggregation  in this sample was  found to be governed by intermolecular disulphide and isopeptide bonds and/or other N-crosslinks between the proteins.  EWP samples treated at 50℃ and 70% RH also contained protein aggregates, but these aggregates seemed to be mostly stabilized by disulphide bonds. Overall, T-RH treatments at low temperature (<50℃) and low RH (< 50%) did not seem to significantly affect the physicochemical properties of the proteins in the EWP powder. However, none of the T-RH treatments enhanced the studied functional properties, i.e. foaming, emulsifying and gelling properties.