Salmonella Penetration through Eggshell Associated with Freshness of Laid Eggs and Refrigeration

Abstract

Effects of egg age after laying and refrigeration on penetration of the eggshell by Salmonella enteritidis (SE) and Salmonella typhimurium (ST) were examined. Eggs 0.25 to 3 h, 3.25 to 6 h, 1 day, and 7 days old held at two temperatures were immersed in SE or ST suspensions containing 10(3) or 10(6) CFU/ml at 25 degrees C for 10 min. After holding at 25 degrees C for 2 h, the inner eggshell and egg contents were examined for Salmonella cells. The recovery rates of Salmonella cells from both the inner eggshell and egg contents of the 0.25- to 3-h-old eggs were significantly higher than those of other groups, especially at the high-exposure dose. There was no significant difference noted between SE and ST in ability to penetrate through eggshell. Salmonella penetration was significantly decreased by cooling the eggs at 4 degrees C for 15 min prior to immersing them in SE or ST suspension. The data suggested that Salmonella cells readily penetrated through the shell of freshly laid eggs, but that this penetration was suppressed by cooling the eggs before they were exposed to Salmonella suspensions.

Physicochemical and functional properties of shell eggs following electron beam irradiation

“…24 However, bacterial growth in albumen can be restricted by a number of unique nutritional and physiological features, including iron chelation by conalbumin, limited amino acid or glucose content, antibacterial activity of lysozyme, high alkaline pH and restricted motility in the viscous thick albumen. 25 An initial increase (p < 0.05) in bacterial count for inoculated pathogens of L monocytogenes, E coli and S typhimurium occurred in the albumen after 1 day of storage (Table 1).…”

Salmonella spp.: O ovo como veículo de transmissão e as implicações da resistência antimicrobiana para a saúde pública

“…Porém, as estruturas da casca são especialmente vulneráveis logo após a postura, ou seja, antes de ocorrer a secagem da cutícula (BERRANG et al, 1999). Esta vulnerabilidade pode ser reforçada pelos resultados obtidos por Miyamoto et al (1998), que reportaram taxas de recuperação de Salmonella das membranas internas da casca e do conteúdo de ovos significativamente maiores quando os mesmos foram expostos à contaminação nas três primeiras horas após a postura.…”

Effect of low cost shell coatings and storage conditions on the raw and cooked qualities of shell egg Efecto de recubrimientos de cascara de bajo coste y de las condiciones de almacenaje sobre la calidad de huevos crudos y cocinados

“…In Nigeria for example, poultry eggs are predominantly cooked and consumed as hard-boiled eggs or used as ingredient in food preparation like salads dressing and snacks such as Scotch egg and other egg rolls. Although refrigeration of egg is expected to result in longer shelf life and reduce spoilage, by reducing the possibility of infection of the internal portion by the spoilage-and disease-causing organisms (Miyamoto, 1998), reports on the effect of refrigeration on the consumption quality are rarely published.…”