ISOLATION, ENUMERATION, AND IDENTIFICATION OF GRAM-POSITIVE COCCI FROM FROZEN CRABMEAT

Bacterial levels in frozen crabmeat samples were determined by plate c ounts using four staphylococcal isolation media incubated for 24, 48, and 72 h at 26 and 35 degrees C. Staphylococcal counts determined by t he spread-plate Food and Drug Administration Baird-Parker protocol inc ubated at 35 degrees C for 48 h (FDABP48-35) served as the standard fo r comparison. When FDABP48-35 counts were compared to counts from 29 c ombinations of media, time of incubation, and incubation temperature, only FDABP and Borrego, Florido, Mrocek, and Romero (BFMR) counts, rep resenting 11 combinations, were statistically comparable to FDABP48-35 counts. Cocci (91.5%) were the dominant bacterial type; gram-positive rods (8.3%) and gramnegative isolates (0.2%) were also detected. Isol ates tested by the coagulase reaction were predominantly coagulase neg ative (CN) (97.7%). Of 100 isolates analyzed by the BIOLOG identificat ion procedure, 62% were classified as Staphylococcus lentus, S. homini s, and S. epidermidis. Three isolates were identified as Staphylococcu s aureus. These data indicate that species identification of staphyloc occi from crabmeat can assist in determining the source of contaminati on, and that staphylococcal isolates from crabmeat are more likely to be coagulase negative.