Impact of ozone and UV irradiation sanitation treatments on the survival of Salmonella and the physical–chemical characteristics of hen eggs

Abstract

Summary: Salmonella is the second main cause of foodborne illness in poultry production. It is one of the most problematic zoonoses in terms of public health worldwide because of the difficulty in controlling it and its significant morbidity and mortality rates. Recent surveys have shown that small flocks of laying hens have the same or higher prevalence of salmonellosis than larger flocks, mainly due to a lack of control actions, that is, the control of mice and wild animals, employees, and poor management practices. In this regard, different physical and chemical procedures have proven efficacious for reducing external and/or internal Salmonella contamination. This research evaluated the effect of ozone and UV-C rays on Salmonella growth and hen egg quality. Microbiological evaluation was performed on 120 eggs: negative control (C−), eggs not contaminated with Salmonella; positive control (C+), eggs contaminated; contaminated ozonate-treated (O, 600 mg/h for 2 h); and contaminated UV-C–irradiated (ʎ, 254 nm for 15 s) eggs. Moreover, 30 eggs were used (10/group) for the quality assessments of the C, O, and UV-C groups. A 2 log10 CFU/g reduction in Salmonella on contaminated eggs was found in the UV-C group compared with the C+ and O groups. Compared with UV-C treatment, ozonization reduced the amount of yolk tocols and carotenoids (by 2 times). The lipid oxidative status decreased (−1.5 times), similar to the cholesterol level (−28.5%), whereas the amount of cholesterol and its oxidized products increased (+82.1%) in the O group compared with the C group. UV-C irradiation is an effective strategy to reduce Salmonella contamination in eggs without negatively affecting the quality. Therefore, UV treatments remain among the more promising procedures.

Keywords

• eggs
• ozone
• UV
• antioxidants
• cholesterol
• oxidation