Microorganisms can be divided and analyzed into the following categories and standards:


CategoryTreatmentMin.°COptimum.°CMax. °CStandard
Psychrophilic cell-151020
Psychrotrophic cell-52535ISO 6222ISO 21527-1,  ISO 21527-2
Mesophilic cell

Mesophilic spore

10 min 80°C

103545ISO 4833-1,  4833-2

NEN 6813

Thermoduric cell

Thermoduric cell and spore

30 min 63,5°C

154550NEN 6808 ONLY for Streptococcus thermophilus

NEN 6808 ONLY for Streptococcus thermophilus

NEN 6807 for all other micro-organisms (incubation 30°C)

Thermophilic cell

Thermophilic spore

30 min 100°C

405570Not (yet) available

NEN 6809

Table 1: according to Microbiologie van voedingsmiddelen 2015

Psychrophilic microorganisms are cold-loving organisms. These bacteria, moulds, and yeast can grow at refrigeration temperatures. Most psychrophilic bacteria can be found in alpine soils, ice formations, and deep oceanic waters. Most of these psychrophilic are Archeas, but also some fungi and yeast.


Psychrotrophic bacteria, yeast, and moulds can grow at room temperature and refrigeration temperatures. These psychotropics can cause spoilage in food and water.

CRM products for the total psychrotrophic count:

Mesophilic count

Mesophilic microorganisms are those that can grow well at body temperatures. This group of microorganisms includes most pathogens.

CRM  for the total mesophilic count:


Thermoduric bacteria do not love high temperatures but can survive a period exposed to high temperatures. These bacteria can survive pasteurization.

CRM  for the total thermoduric count:

Thermophilic bacteria

Thermophilic bacteria love to live in high temperatures environments. This can be an indicator of poor hygiene in the dairy industry.

CRM  for the total thermophilic count:



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