Penetration of salmonella enteritidis into eggs subjected to rapid cooling

Eggs were cooled to 0°C using two different cooling rates, natural convection, and forced convection at an air speed of 30.5 m/min. Upon rapid cooling using forced convection and when brought back to room temperature, eggs were more prone to penetration by Salmonella enteritidis (strain PS8NSR). Eggs cooled using forced convection had 100% penetration by PS8NSR; eggs cooled using natural convection had 91.3% penetration; and uncooled eggs had 48% penetration. Scanning electron microscopy revealed that shells of both cooled and uncooled eggs had microscopic cracks; however, cracks were more numerous and larger in shells of cooled eggs.