What is the sufficient volume of the microbial suspension of not more than 100 CFU? What does 100 CFU refer to?
A. The micro-organisms are to be added to the diluted/suspended product at the end of the preparation (usually a 1 in 10 dilution is prepared) or after the neutralization (in the last fraction of the rinsing fluid in the case of filtration or simultaneously with the preparation in/on the Petri dish in the case of the plate count method) if inhibition of growth by the sample cannot otherwise be avoided. The 100 CFU refers to the inoculum (e.g., what will be on the filter or on the plate).
