Interlaboratory evaluation of the AOAC method and the A-1 procedure for recovery of fecal coliforms from foods.

An interlaboratory evaluation was made of the 96 h AOAC method and the 24 h A-1 procedure for the enumeration of fecal coliforms in samples of yellow corn meal, rye flour, mung beans, raw ground beef, and raw oyster homogenate. Results indicated that the efficiency of the A-1 procedure, measured in terms of recovery of fecal coliforms, and the reproducibility of that recovery were dependent on the particular food being analyzed. Accordingly, until its efficiency can be more fully demonstrated, the A-1 procedure is recommended only as a screening procedure for fecal coliforms in foods.