How to enumerate the microorganisms in a food sample using Dilucup?
- First homogenize the sample if it is solid. This is the first 1/10 dilution.
- Once the sample is suspended or if the sample is liquid, serial dilute it using Dilucup.
- Plate 1 mL of the selected suspension(s) and incubate.
- Count the colonies (the plates should have between 30 and 300 CFUs to get a statistically valid result).
- Divide the average number of CFUs per the dilution level to get the number of microorganisms per mL or g in the original sample.
Watch the video to understand it better!