"Staph", as this common food-borne disease is nicknamed, is caused by a toxin produced by the bacterium Staphylococcus aureus. That microorganism creates the toxin most readily in the 40o
F temperature zone, particularly in low-acid foods. Custard-filled foods are notorious sources of staph. Such foods should not be left out of the refrigerator for long.
For the record, mayonnaise has been given a bum rap: It's not the underlying reason chicken and other mayonnaise-dressed salads become contaminated under the hot sun at picnics. In fact, the relatively high salt and vinegar-lemon content of commercially prepared mayonnaise slows down bacterial growth. The real culprits are low-acid ingredients such as the chicken. However, homemade mayonnaise usually is too low in acid and salinity to retard the bacterial growth.
** Asian Recipes