Environmental Monitoring
We recently had an audit, and they said that we cannot have a range for E.coli testing for environmental testing in HZ1. We are a dry food manufacturing facility (cake mixes, flour, hot cocoa etc.) that uses indicator organisms for the testing process. The range we had was <10cfu or less and no greater that <20cfu. I am at a lost on what to do as this has been our standard for over 4yrs. and no other audit called it out. I have been looking for guidance and most say it is up to the company.
Can anyone help us
Stacy
You certainly do not want any E.coli in zone 1. However, I can see why your lab is reporting it <10 even when there is none on petri dish. It is due to dilution factor.
Have you ever had any results that were not reported <10? You should specify your range as none or <10 in your guidance.
You could also ask your lab to test at a higher dilution, which then would result in <1 on your report when no growth detected.
I hope this helps!
Hi Stacy,
Swab results should be reported in cfu/cm2. It isn’t a massive issue to have a range as long as the standards are acceptable. I think the auditor may have been saying that you cannot have a range because E.coli should be ‘Not Detected’?
Clean surface standards are typically around:
TVC < 100 cfu/cm2 Food Contact < 1,000 cfu/cm2 target for other surfaces.
E.coli < 1 cfu/cm2 Food Contact < 10 cfu/cm2 target for other surfaces.
The standards are dependent on the area swabbed and the product. For high-risk RTE products and E.coli* positive on a food contact surface would need further action to ensure the product wasn’t contaminated.
* The infective dose of some E. coli for example O157:H7 is believed to be very low (10–100 cells).
For products that are meant to be cooked this is obviously far less serious.
For some useful background information on swab standards worldwide see the Micro. Guidelines for Food Contact Surfaces forum here where the late great Charles C posted a Compilation of International Micro. Guidelines for food contact surfaces, 2000 onwards. I think it is what you are looking for.
Kind regards,
Tony
Are your raw materials heat treated for pathogens??? E.G. is the flour supposed to be free of coliforms?
Your testing process depends on what your incoming product specs are......
We recently had an audit, and they said that we cannot have a range for E.coli testing for environmental testing in HZ1. We are a dry food manufacturing facility (cake mixes, flour, hot cocoa etc.) that uses indicator organisms for the testing process. The range we had was <10cfu or less and no greater that <20cfu. I am at a lost on what to do as this has been our standard for over 4yrs. and no other audit called it out. I have been looking for guidance and most say it is up to the company.
Can anyone help us
Stacy
Being positive or having a range for E.coli in zone 1 - no you can't. However it sounds like you use indicator organisms.
Are you using Enterobacteriaceae or a different indicator organism.
I'm also a dry mix producer, and my E. Coli results are reported as 'Negative'.
As far as testing by the specs, it's difficult with flour based non RTE stuff, as the specs for flour basically say "This will contain pathogens and is not considered a RTE food', or something of the sort. So yeah, coliforms are always an issue, resulting in pretty high coliform acceptability levels. Even still, I can have a mix tested and have a coliform limit that is thru the roof, and another sample from the same bag with extremely low results. It's a pita.
Your dry mix products are reported as "negative" or env samples?
Your dry mix products are reported as "negative" or env samples?
yeah, i don't enviro zone one any longer. zone 1 is atp only. Other zones I don't do e. coli anymore, I do enterobac. When I did do e. coli it was reported as <1....
Sorry, should have clarified there....
Yes we only use indicator organisms in Zone 1 for environmental testing.
All raw material from suppliers are tested for E.coli
Stacy
We don't test incoming raw anymore. Pointless. If you have a raw ingredient test positive for something that they already tested and found clean, do you expect they will respond? I'd imagine they'll say "we already tested it in our lab, it's clean. Whatever you found is on your end. We have no idea of your collection methods, testing, lab equipment/staff, etc..." So if you get a dirty test, what's your follow up?
Depends on everyone's situation of course, but I stopped testing raw years ago, and every auditor has supported it, and the idea to stop was actually brought up by my internal auditor... Now I just do EM and Finished.