Abstract Cook-chill systems are increasingly being used in the UK as a convenient means of catering for hospitalized patients. When such a system is operational, it is recommended that sampling of food be performed prior to regeneration. At our hospital we have established a food hygiene laboratory to achieve this. On routine sampling of nut roast prepared by the cook-chill method, Salmonella enteritidis was isolated. It was subsequently established that raw egg had been used in the preparation of the food which had been fried. Our investigation thus exposed potentially dangerous practices in the production line and highlights the need for constant vigilance where the system is used to provide food for a relatively high risk population group.