Hello! I recently started working for a company that produces RTE cereal crisps (similar to Rice Krispies). We do not have a validated kill step but I have a customer requesting one. Our process is fairly simple, dry powders are mixed with a small amount of water, extruded, cut, and dried in an oven/toaster. Our product is below 5.5% moisture and aW of 0.40. We do not have an in-house water activity meter, only a moisture meter. I have sent out a few samples to prove the correlation between moisture and aW for my own peace of mind. I have a few questions:
- Where would I find information on how many samples I would need to test to prove that X% moisture is equal to X aW?
- Does validation require a Process Authority or certifying body?
- Once I establish the correlation between moisture and water activity, I would send out finished product monthly to continue to verify, would this be sufficient?
Thank you in advance for your help!