The effect of shell egg pasteurization on the protein quality of albumen

Department of Food Science and Human Nutrition, Clemson University, South Carolina 29634-0371, USA.

The effect of a low-temperature, extended-time, in-shell pasteurization process on the protein quality of egg albumen was evaluated. Ten dozen fresh chicken eggs were pasteurized in a hot-air oven at 55 C for 180 min. The eggs were refrigerated and broken out for analysis on Days 0, 7, 14, 28, 42, and 56 following pasteurization. There were no significant differences in total or soluble protein over the experimental period for the pasteurized or unpasteurized albumen. Mean protein content was 80.6 +/- 0.5% for the pasteurized albumen and 80.9 +/- 0.5% for the unpasteurized albumen. In vitro digestibility, as measured by the AOAC method, was 82.4 +/- 0.7% for the pasteurized albumen and 81.7 +/- 0.6% for the unpasteurized albumen. There were no significant differences over the experimental period in the digestibility of the samples. Free amino acids and discriminant-computed protein efficiency ratio (DC-PER) also did not differ between the pasteurized and unpasteurized albumens or over the experimental period. The in-shell pasteurization process used had no effect on the protein quality of albumen.