While most people associate food poisoning with dairy products, meat, or seafood, the ever-popular holiday ham could be risky as well, suggests a new report from the Centers for Disease Control and Prevention (CDC).
Apparently the high salt and sugar content of pre-cooked canned hams can encourage the growth of the bacteria Staphylococcus aureus if the ham is improperly handled by the consumer. Healthy people can carry the bacteria in their nose and throat, or on their hair and skin, and the organisms are particularly abundant in cuts, pustules and abscesses.
Under the right temperature and conditions, once introduced by careless handling, the bacteria can grow out of control on a ham's moist surface, producing toxic substances along the way -- and potentially causing food poisoning in those who consume the contaminated ham.
Ham is the most commonly reported vehicle of transmission in staphylococcal food poisoning, according to the report. The salt content of precooked, packaged hams is high, often as high as 3.5%, which provides an ideal growth medium for Staphylococcus.
In one such outbreak last September, 18 people developed nausea, vomiting, diarrhea, chills, and muscle aches after eating ham at a retirement party in Florida. It's not clear how the 16-pound ham served at the party became contaminated with S. aureus. But it is known that a food worker first baked the ham at 400 degrees F for one and a half hours and then sliced the ham with a commercial slicer. The ham was then stored in a small plastic container, refrigerated overnight and served the next day cold.
To reduce the risk of food poisoning, the amount of manual handling should be minimal, and food preparers should wash their hands thoroughly before handling food, according to the report. Food slicers and preparation surfaces should be cleaned and sanitized, and ham should be served cold. If served hot, the meat should be cut just before serving to keep bacteria from spreading.
To permit rapid cooling, food should be stored in small portions in containers that are shallow and loosely covered, This method facilitates adequate air flow and rapid transfer of heat from the food to the container.
Morbidity and Mortality Weekly Report (1997;46:1189-1191)