Factors impacting SPC results

- single vs. composite sampling - distribution of microorganisms in food - types of microorgansims in food (oxygen tolerance) - nature of food material (fatty - add emulsifier, acidic- add buffer) - nutritional adequacy of plating medium - pH, aw, redox potential of plating medium - incubation temp. and time - type of diluent used - competing or antagonistic microorgansims