RESCAPE: Innovative techniques for eggs decontamination
Reducing Egg Susceptibility to Contaminations in Avian Production in Europe
|Project acronym: RESCAPE|
|Duration: October 2006-September 2009|
|Funded by: DG Research (FP6)|
|Website: Not available|
Project name: Reducing Egg Susceptibility to Contaminations in Avian Production in Europe
Sub title regarding the application described : Gas plasma prototype for superficial decontamination of table eggs
Contacts: Dr. Lucia Vannini, University of Bologna - Department of Food Science, Viale Fanin 46, 40127 Bologna, Italy, Tel: +39 051 2096576; Fax: +39 051 2096574; email@example.com
1. Context and problematic
The highly competitive market of egg production with its low profit margins has resulted in the development of intensive caged hen egg production in Europe. However, keeping hens on the floor or outdoor could present an increased risk of bacterial contamination since the total count of aerobic bacteria is generally significantly higher for nest eggs from non-cage systems compared to eggs from enriched or conventional cages (EFSA, 2005) even if there is not a common scientific agreement on this subject. Treatments of eggs such as egg washing, currently banned in Europe with the exception of a few countries (e.g. The Netherlands and Sweden) may help to prevent any potential or additional food safety risk for human health, but its use remains controversial and limited in Europe since it is claimed to damage the cuticle of the egg thus favoring the penetration of bacterial pathogens. Therefore, the development of efficient measures alternative to washing for reducing eggshell contamination is a matter of great importance to producers.
2. Results and Applications
Within the RESCAPE project, innovative egg decontamination treatments including hot air and gas plasma exposure, modified atmosphere packaging (MAP) or chitosan coating have been developed and compared. While hot air and gas plasma treatments can be used immediately after the laying of eggs and before their commercialization, (MAP) or chitosan coating are “long-term” approaches in that they are active all over the chain from farm to fork. Both MAP and chitosan coating did not exert an efficient mean to control the bacterial load on shell egg. In fact, no significant difference in the cell load of S. Enteritidis in experimentally contaminated eggs was detected over a 45-days storage regardless the gas used in the MAP or with respect to uncoated eggs. As far as the other two techniques, a significantly higher efficacy was evidenced for gas plasma than hot air in reducing the initial loads of S. Enteritidis, L. monocytoges, E. coli contaminating the surface of the eggs. On experimentally contaminated eggs, a 3 to 4 log reduction was observed after gas plasma treatment in comparison to a ≤ 1 log reduction equal for hot air treated eggs. Such a difference was lower for naturally contaminated eggs with a 1.5 log reduction on gas plasma treated eggs versus 1 log reduction on hot air treated eggs. Regarding egg quality, no influence was detected in shell eggs treated with hot air or gas plasma, while both MAP and chitosan coating treatments positively affected some quality traits of eggs during storage (Haugh Unit, albumen pH and weight loss).
3. Novelties, benefits and added value
The research activities carried out within the RESCAPE allowed the identification of promising and efficient treatments which could be used for the superficial decontamination of eggs, i.e. hot air and cold gas plasma treatments. Moreover, the observed improvement in some quality traits of MAP or chitosan coated eggs could be exploited by food industries producing egg-based ingredients or products.