Yersinia enterocolitica is one of the few human pathogens that grow at refrigeration temperature for foods, 0–5 C. Typical strains of Y. enterocolitica do not ferment rhamnose. These have been recovered from human infections, various animals, and pig's feces, but only rarely from foods. The atypical strains tend to utilize rhamnose, raffinose, esculin, salicin, a-methyl glucoside, or Simmon's citrate. These atypical strains have been recovered from fish, meat, oysters, and water as well as human patients. Inoculated food studies indicate that present recovery methods for Y. enterocolitica need improvement, but its identification is uncomplicated provided that the typical and atypical strains are taken into consideration. The public health implication of its presence in foods cannot be assessed until the incidence and virulence of the food isolates are determined.