Breaded chicken coated in whey protein isolate (WPI) has been shown to reduce oil absorption during batch frying. What is not known is how this is affected by repeated fryings and whether antioxidant-rich oil will enhance this effect. The objective of this research was to determine how successive daily frying of WPI-coated breaded chicken in antioxidant-rich oil affects oil quality and oil inhibition, moisture retention, color, and texture of the breaded chicken. Chicken fritters with and without a 10% WPI post-breading dip were fried successively for 6 h per day over five days in oil without antioxidant or with either 1000 ppm rosemary extract or propyl gallate. The control oil became spent at 12 h of frying (>24% TPM, <50% DEGLEV). During this time, the oils treated with antioxidants were significantly less spent, and the WPI-treated fritters fried in these oils exhibited 22-49% less lipid; retained 10-18% more moisture; and became darker, less red, and less yellow (lower L*, a*, and b* values) compared to the un-dipped fritters fried in the control oil. These results suggest that the presence of antioxidants in the frying oil mitigated some of the degradative changes in the oil during frying but likely did not play a major role in moisture retention or inhibition of oil absorption.
Keywords: lipid reduction; oil stabilization; total polar materials; whey protein isolate.