What is considered to be an acceptable level of total coliforms for ready-to-eat grains? Obviously the ideal level is zero, but at what point do total coliforms become a health hazard? This is assuming e.coli is NOT present. Seems like the spec requirements vary greatly depending on the manufacturer.
Thank you in advance.
I presume you are referring to the processed/finished product.
"Coliform" is a (variable) group of bacteria. It's level in a finished product is sometimes regarded as an indicator for the hygienic "quality" of the product's process environment.
Coliform is not regarded as a direct health hazard in the haccp "sense", ie not a pathogen.
(generic) E.coli has a similar interpretation to above but is a species.
So there is no meaningful answer to yr health query.
In the general/sanitary micro. quality sense, a spec. like m=10, M=100 cfu/gram is IMEX typical but this may vary depending on the microbial profile of the raw material, etc.
Just as an example of subjectivity, IIRC, the EU's generic E.coli limit for fresh produce is 1000cfu/gram with respect to RTE product/processes.