An analysis of the microflora of broken eggs used in confectionery products in Negeria and the occurrence of enterotoxigenic Gram-negative bacteria

Modified pressure imaging for egg crack detection and resulting egg quality

Cracks in the shell surface compromise the primary barrier for external microbial contamination of the egg. Microcracks are very small cracks in the shell surface that are difficult to detect by human graders. New technology has been developed that uses modified pressure and imaging to detect microcracks in eggs. Research has shown the system to have an accuracy of 99.6% in detecting both cracked and intact eggs. A study was undertaken to determine if quality differences existed between modified pressure imaged and control eggs during extended cold storage. Three replicates were conducted with eggs stored at 4 degrees C for 5 wk with weekly quality testing. The physical quality factors monitored were Haugh units, albumen height, egg weight, shell strength, vitelline membrane strength and elasticity, and whole egg total solids. All measurements were conducted on individual eggs (12/treatments per replicate) each week with the exception of whole egg solids, which were determined from 3 pools (4 eggs each)/treatment per replicate each week. Percentage of whole egg total solids was the only significant difference (P < 0.05) between treatments (23.65% modified pressure imaged and 23.47% control). There was a significant difference (P < 0.05) for egg weight between replicates (60.82, 58.02, and 60.58 g for replicates 1, 2, and 3, respectively). Therefore, imaging eggs in the modified pressure system for microcrack detection did not alter egg quality during extended cold storage. Utilizing the modified pressure crack detection technology would result in fewer cracked eggs reaching the consumer, consequently enhancing food safety without affecting product quality.

Thermal resistance of Salmonella enterica serotypes, Listeria monocytogenes, and Staphylococcus aureus in high solids liquid egg mixes

Decimal reduction times (D-values) were determined for Salmonella enterica serotypes, Listeria monocytogenes, and Staphylococcus aureus in two high solids egg mixes designated A and B (water activity [a(w)] = 0.76 and 0.82; solids = 53.12 and 52.63%; pH = 5.09 and 5.29; viscosity = 183 and 119 centipoise/s, respectively) using a low-volume (0.06 ml) sealed glass capillary tube procedure. For Salmonella, D-values ranged from 0.035 (70 degrees C) to 0.193 min (64 degrees C) in product A and from 0.048 to 0.193 min in product B. For Listeria, D-values ranged from 0.133 (70 degrees C) to 0.440 min (64 degrees C) in product A and from 0.074 to 0.364 min in product B. For Staphylococcus, D-values ranged from 0.332 (70 degrees C) to 1.304 min (64 degrees C) in product A and from 0.428 to 1.768 min in product B. For Listeria, the D-values of all heating temperatures were significantly higher (P < 0.01) in product A than in product B. The similar trend was also observed for Salmonella and Staphylococcus but only at 66 degrees C for Salmonella and 64 degrees C for Staphylococcus. Greater temperature dependence was observed for Salmonella inactivation in the low a(w) and low pH product (A), while the product (B) with the higher a(w) and pH had greater temperature dependence for Listeria. Compared across both egg mixes and all heating temperatures, the Staphylococcus strains were from 6.2 to 11.7 times more heat resistant than S. enterica serotypes and from 2.2 to 7.5 times more heat resistant than L. monocytogenes.