2 replies to this topic

[Nuttawut.s]

Hi everyone

  I have some question about the limit of pathogen in defference unit like 

some standard is  S. auresu = Not deteced in 0.1 g , another is  S. aureus = Not detected in 10 g 

 

I understand that not detected in 10 g is tighten (cover) 0.1 g , am i right ? 

 

Not detected in 10 g  > Not deteced in 0.1 g 

[Tony-C]

Hi Nuttawut.s,

 

Welcome to the IFSQN forums.

I think I’ve got the gist of your question. Not detected in 10g is a test that is 100 times more sensitive than not detected in 0.1g

 

Kind regards,

Tony

Edited by Tony-C, 07 June 2022 - 04:58 AM.

[moskito]

Hi Nuttawut,

 

for assessment you need some more information e.g. the sampling plan etc.

example:

Salmonella-"free" is often written as n.d. in 25 g

The result can be based on

a) one sample of 25 g is taken from a large batch

b) 30x 25g samples are taken in a representative mode from the same batch -> is often written as n.d. in 25 g too
    (we have performed such sampling by automatic valve during loading e.g. for chocolate)

From statistical point of view there is a huge difference for a risk assessment. 

Example b is sometimes written as n..d in 750 g. But it will not become clear whether the result is based on one sample of 750 g or 30 samples of 25g.

The better way to write e.g. micro specs as n, c, m , M as described here on p 15

microbiological-specifications-nestle.pdf

 

Rgds

moskito