Qualitative exposure assessment for Salmonella spp. in shell eggs produced on the island of Ireland

Abstract

A qualitative exposure assessment for Salmonella in eggs produced on the island of Ireland was developed. The assessment was divided into three main modules (production and packing, distribution and storage, and preparation and consumption), and each of these stages into defined steps in the exposure pathway. In the production and packing stage the initial prevalences of Salmonella in the contents and on the shell of eggs were estimated to be negligible and low respectively. Numbers of Salmonella both in and on eggs were estimated to be low. At each subsequent step in the pathway, qualitative assessments were made of the impact of events on the probability and level of Salmonella contamination on the shells and in the contents of eggs. At the end of each module assessments were combined to give an overall probability and level of Salmonella contamination. In the first two modules the assessment focused on the effect of the duration and temperature of storage on yolk membrane integrity and the likelihood of shell penetration. During the final stage the influence of factors such as safe-handling procedures, pooling practices, consumption patterns and the effectiveness of cooking, on the prevalence and level of Salmonella contamination in a food item at time of consumption was assessed. The outcome of this assessment was an estimate of a low probability and level of Salmonella contamination of egg-containing foods, prepared with eggs produced on the island of Ireland.

Lag Phase of Salmonella enterica under Osmotic Stress Conditions

“…Models for the lag and the "work to be done" as a function of the water activity showed similar properties, but in rich medium above 5% salt concentrations, the data showed a maximum for this work. An accurate description of the lag time is important to avoid food wastage, which is an issue of increasing significance in the food industry, while maintaining food safety standards.Salmonella enterica causes severe enteritis in both humans and animals (19,25). Human infection usually results from eating contaminated food, such as poultry, milk, beef, eggs, pork, and seafood (13); consequently, monitoring and control of contamination by Salmonella are necessary and important in the food industry.…”

Determination of Salmonella in egg shell and egg content in some selected areas of Bangladesh

“…The variation may be due to individual sampling in comparison to pooled survey sampling [26] . Other study in Belgium, New Zealand, Australia, and Canada reported a range of 2-13% salmonella infection in large sampling frame as part of public health surveillance system [26][27][28] . A study on table egg in Dhaka city showed overall 14-17% inner egg and 18-31% egg shell contamination with Salmonella Spp.…”

Elimination of Salmonella enterica serovar Typhimurium in artificially contaminated eggs through correct cooking and frying procedures

“…In almost all cases, salmonellosis is caused by the consumption of foods containing raw or insufficiently cooked eggs (GUArD-PeTTer, 2001;GANToIS et al, 2009;PereSI et al, 1998;mUrChIe et al, 2008;meNSAh et al, 2002), which guarantees the persistence of contamination by Salmonella species. This contamination occurs even when there are low quantities of bacteria in yolk or albumen (hUmPhreY et al, 1991) and mild conditions of temperature, as evidenced by Grijspeerdt and herman (2003), who reported that S. typhimurium growth was satisfactory at 25 °C.…”

“…Then, 100 µl of the suspension (10 6 CFU.ml -1 ) was inoculated with a needle (25 × 48 mm) connected to 1 ml syringe into each egg at the 2 o´clock position in an approximately parallel path. The final bacterial concentration was approximately 10 4 CFU.g -1 of yolk (PereSI et al, 1998;NAmATA et al, 2004;mUrChIe et al, 2008). The position and size of the syringe was previously confirmed inoculating 100 µl of gentian violet, instead of the inoculum, in three eggs and breaking them into Petri dishes to visualize the presence of the dye in the yolk (CoGAN et al, 2001).…”

“…The consumption of raw or slightly cooked eggs (in mousse, mayonnaise, beverages and other foods) contributes to an increase of the salmonellosis rate (rADForD; BoArD, 1993;loCK;BoArD, 1995), being necessary an incorporation of hygiene and disinfecting measures in the technology of fresh egg production (SChoeNI et al, 1995;mUrChIe et al, 2008). The risk of microbial contamination is minimal for hard-boiled eggs, but medium and certainly soft-boiled eggs are a potential risk factor for salmonellosis.…”