Egg disinfection is an important issue to the poultry industry. In order to reduce egg shell contamination, three experiments were conducted at the Texas A&M University in College Station, USA.
The aim was to evaluate treatment parameters in an effort to optimize the reduction of eggshell surface microorganisms using UV light (UV) and hydrogen peroxide. A UV chamber equipped with UV-C lamps (254 nm) was used in combination with hydrogen peroxide sprayed onto the eggs immediately before UV exposure.
In the first experiment, eggs were sprayed with 3%, 4.5% or 6% hydrogen peroxide before UV exposure for 1 or 2 min. Total aerobic microorganism enumeration was accomplished by rinsing eggs in phosphate buffered saline and plating rinsate onto tryptic soy agar. Results indicated that 3% hydrogen peroxide reduced microbial counts (log10 cfu/egg) equal to 4.5% and 6%. It was also found that 1 min of UV exposure was as equally effective as 2 min.
The second experiment examined the effect of repeated applications of the combination of hydrogen peroxide and UV exposure. UV was administered for 1 min in combination with 3% hydrogen peroxide for 1, 2 and 4 applications. Data indicated that 2 applications resulted in lower eggshell microbial counts than 1 application, but 4 applications did not provide further reductions compared with 2 applications.
In the third experiment, the effect of UV intensity in combination with hydrogen peroxide was investigated. Three UV intensities were used: high (14 mW/cm2), medium (8 mW/cm2), and low (1.3 mW/cm2). A total of 96 eggs were used for the treatment groups (32 eggs/treatment) and 16 untreated eggs served as controls. Results indicate that the medium intensity was equally as effective compared with the high, but the low intensity yielded the highest eggshell counts.
The combination of these experiments has further defined the methodology for a simplistic eggshell disinfection technique that could have many applications in the commercial poultry industry.
Source: S. M. Gottselig, K. S. Woodring, and C. D. Coufal, Texas A&M University; Proceedings of the International Poultry Scientific Forum 2011, Atlanta, USA