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Help interpreting e. coli reading results

Started by , Mar 27 2018 04:40 PM

MPN - most probable number.  <0.3 MPN usually means that results are below detectable levels for that particular test. So can't say for sure that sample did not contain E. coli  at all (can't really ever say that), but that the levels were below detectable levels. 

4 Replies

I have a question, a costumer requested an E.coli test on pasteurized almonds, this is the result from the lab:

E. Coli / AOAC 966.24

E. Coli 1 <0.3 /g MPN (what this means?)

 

so the 0.3 means that is contaminated with e. coli?

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MPN - most probable number.  <0.3 MPN usually means that results are below detectable levels for that particular test. So can't say for sure that sample did not contain E. coli  at all (can't really ever say that), but that the levels were below detectable levels. 

1 Thank

thank you so much

I have a question, a costumer requested an E.coli test on pasteurized almonds, this is the result from the lab:

E. Coli / AOAC 966.24

E. Coli 1 <0.3 /g MPN (what this means?)

 

so the 0.3 means that is contaminated with e. coli?

 

Hi svg87,

 

Previous post2 is "operationally" correct.

 

Statistically the "<" means that the sets of tubes used to test for the species were all negative, ie no detection. Mathematically this does not yield a specific answer for the MPN.

 

So the (most likely) answer for the MPN is then "interpreted" as being less than the (most likely) value would have been if One tube had been positive. And that value in yr case was (apparently) 0.3cfu/gram.

 

PS - Just for illustration here is one set of tubes (3x3x3) where the (null) result was < 3 cfu/gram

 

MPN table.png   83.68KB   0 downloads

2 Thanks

thanks Charles :spoton: 


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