Press it with a spatula and squeeze some juices from the patty. Juices from fully cooked meat should have no traces of pink color. Two types of meat can be served rare if cooked properly. Roast beef may be served rare if cooked to 13O degrees F for a minimum of two hours. The external surfaces are exposed to micro-organisms, so as long as the outside is cooked, the steak is safe to serve if it has not been subjected to time and temperature abuse.
Staph bacteria grows well in high salt concentrations and in high sugar concentrations.
It will also survive freezing. Since it is the toxin that is poison and not the bacteria itself food poisoning may occur even after the bacteria has been killed by heat. The most common source of Staph bacteria is the human body. Even healthy people carry the bacteria in their mouths, throats, noses, pimples, and infected wounds. When an infected person does not use proper food handling techniques they may transfer the Staph bacteria to food.