total count method
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How to enumerate microorganisms in food products?

Total count method:

  1. Prepare the sample:
  • If it is solid: take a small quantity and homogenize it with a diluent so that you have a first dilution 1/10.
    For instance: 10 g of minced meat + 90 mL of MRD (Maximum Recovery Diluent).
  • If your sample is already liquid, skip this step.
  1. Perform serial dilutions with the Dilucup® System to reduce the concentration of microorganisms to a countable range.
  2. Plate and incubate: place 1 mL of the diluted suspensions on agar plates or equivalent and incubate them. This step will allow microorganisms to become visible colonies.
  3. Count the colonies after incubation. Plates should have between 30 and 300 Colony-Forming Units (CFU) to ensure statistical validity.
  4. Calculate the number of microorganisms per millilitre or gram in the original sample by dividing the number of CFU by the dilution factor.
    For example: 131 CFU / 10-2 = 1,31 x 104 CFU/g.

Enumerating microorganisms in food products is an essential analysis to ensure the quality of the product and its safety for consumption.

With the Dilucup® System you save a lot of time with serial dilutions and get accurate results.