Ultrasonic Vibration as an Aid in the Acetic Acid Method of Cleaning Eggs

Abstract Experiments were conducted to evaluate the use of ultrasonic vibration as an aid to the dilute acid method of cleaning eggs. It is expected that ultrasonics could increase the efficiency of cleaning by reducing the length of time the eggs are exposed to the acid solution. To determine whether ultrasonics could be beneficial, penetration of the cleaning solution into the egg, shell thickness, shell cleanliness, interior quality, and microbial, organoleptic, and functional properties were measured. Shell penetration was less, as a result of ultrasonic vibration, when the egg and acetic acid solution were the same temperature (22 C) at time of washing than when the eggs were 22 C and the solution was either 12 or 32 C. When egg and cleaning solution were 22 C, no cleaning solution penetrated the shell after 5, 10, 20, 40, and 80 sec of exposure but penetration increased after 160 and 320 sec of exposure. No differences (P>.05) in shell thickness resulted from cleaning in 1, 2, or 3% acetic acid with ultrasonic vibration for 30, 60, 120, and 240 sec, and the shell thickness of eggs so treated did not differ (P>.05) from that of commercially washed eggs. All three solutions produced clean eggs at each exposure time, and their cleanliness was comparable to that of commercially washed eggs. No differences (P>.05) in Haugh units were caused by length of exposure to the cleaning solution and by exposure to ultrasonics. After 4 weeks storage at 22 C only eggs exposed to ultrasonics in the 1% solution had lower (P After storage for 1, 2, 3, and 4 weeks at 23 C eggs washed in 3% acetic acid with and without ultrasonics had one log cycle less (P .05) were found to have been caused by ultrasonic vibration during washing with 3% acetic acid.