Scientific Opinion on the public health risks of table eggs due to deterioration and development of pathogens

Abstract

Salmonella Enteritidis is considered the only pathogen currently posing a major risk of egg-borne diseases in the European Union (EU). The possible impact of extending the shelf-life of eggs on the risk to consumers posed by S. Enteritidis was estimated by applying a quantitative model and comparing the actual situation regarding the storage of eggs in the EU with different possible scenarios combined, considering the prolongation of the bestbefore and the sell-by date from 7 to a maximum of 70 days. Extending the sell-by date by one week (from 21 to 28 days), but leaving the best-before date unchanged, is estimated to result in a relative risk of illness of 1.4 and 1.5 for uncooked and lightly cooked egg meals respectively, compared to the current situation. If the best-before date is also extended by one week (from 28 to 35 days), the relative risk would be 1.6 and 1.7. In the worst case scenario considered (sell-by date of 42 days, best before date of 70 days), such figures would be 2.9 and 3.5. It should be noted that the absolute risk is greater for uncooked meals compared to lightly cooked meals. An effective way to minimise any increase in risk during extended storage is to keep the eggs refrigerated both at retail and the household. Regarding egg spoilage, such events strongly depend on the hygienic conditions of egg production and practices of egg handling, including storage times and temperatures. Finally, the impact of the prolongation of storage time on the quality criteria for eggs (3-hydroxybutyric acid and lactic acid) destined for manufacturing of egg products is considered negligible. Specifically, EFSA was asked to assess: (i) the public health risk posed by relevant pathogens and in particular by Salmonella in the consumption and handling of table eggs (Term of Reference, or ToR1), (ii) the public health risk deriving from deterioration (ToR2) and (iii) possible consequences for public health of an extended shelf-life of table eggs for the specific freshness criteria for egg products as laid out in the hygiene package (ToR3). © European Food Safety Authority, 2014 KEY WORDSIn order to answer the first ToR, the BIOHAZ Panel based its conclusions on the results of a quantitative model, aimed at describing the behaviour of Salmonella Enteritidis following vertical transmission, since this serovar is recognised to be the major pathogen related to egg-borne disease because of its ability to contaminate the interior of intact eggs during their formation within the body of an infected hen. The possible impact of extending the shelf-life of eggs on other serovars of Salmonella, as well as on other pathogens, is evaluated in a qualitative manner, with no individual serovar other than S. Enteritidis currently posing a major risk of egg-borne salmonellosis in the European Union (EU), although S. Typhimurium has been associated with relatively small outbreaks due to duck eggs. Trans-shell contamination (i.e. secondary contamination) is also discussed, but the impact of a prolongation of the shelf ...

The European Union summary report on trends and sources of zoonoses, zoonotic agents and food-borne outbreaks in 2013

“…Salmonella was rarely found in table eggs or products of vegetable origin. The fact that eggs and egg products were still the most important source of food-borne Salmonella outbreaks in 2013 might be explained by the fact that, as mentioned in a recent EFSA BIOHAZ Panel opinion (EFSA BIOHAZ Panel, 2014), very large numbers of eggs are eaten and eggs are very important and complete foods not only for their nutritional aspects, but also for their functional properties, i.e. the coagulant capacity of proteins, the foaming capacity of albumen proteins, the emulsifying capacity of the yolk, etc.…”

The European Union summary report on trends and sources of zoonoses, zoonotic agents and food‐borne outbreaks in 2014

“…At the same time, the number of S. Enteritidis isolates reduced from 282 to 257, which is a reduction of only 8.9%. Therefore, the proportion of Salmonella isolates from laying hens being typed as S. Enteritidis has actually increased from 37.2% to 43%, and this serovar is recognised as being the only one of major significance in terms of contamination of eggs, because of its special ability to invade, survive and multiply within intact eggs (EFSA BIOHAZ Panel, 2014).…”

Global Gene-expression Analysis of the Response of Salmonella Enteritidis to Egg White Exposure Reveals Multiple Egg White-imposed Stress Responses

“…Studies on the antimicrobial activity of egg white generally employ Salmonella enterica serovar Enteritidis as the model bacterium as it represents the predominant (90%) serotype responsible for foodborne diseases (salmonellosis) resulting from egg or egg-product consumption (EFSA BIOHAZ Panel, 2014). Moreover, egg products (whole, yolk, or liquid egg white) are used in the fabrication of various foodstuffs (sausages, sauces, cakes, pasta, etc.)…”