Effect of Radio Frequency Energy for Intervention Processing on the Quality of Intact Eggs

Abstract

During conventional pasteurization, eggs are submerged for 60 min at 56.7 °C, a lengthy and costly process that affects egg quality. Radio frequency (RF), a means to pasteurize eggs without affecting quality, is a novel option based on fast volumetric heating; however, there is scarce information about the quality of such treated food. This research consisted in a comprehensive quality study on eggs treated with RF. The RF system was operated at 40.68 MHz, 40 W and 16 W (8 min total), and 42 rpm. The quality assessment included the determination of Haugh unit, yolk index, compression strength, albumen turbidity, albumen and yolk pH, and yolk color. Additional analyses were conducted to quantify the mineral composition of the eggshell (40.68 MHz, 40 W, 42 rpm, 5.5, 8.5, and 10 min); these samples were observed by SEM. The results showed that RF did not significantly (p > 0.05) change any quality parameters. The mineral composition remained constant in processed eggs. The SEM images of RF-treated eggs showed some smooth spots; however, these areas could exist due to the high variability of the eggshells. RF is an option to process intact eggs, maintaining their fresh quality and keeping the integrity of the eggshell to ensure the food safety of the internal egg components.

Keywords

• eggs
• radio frequency
• food processing
• food quality