Supplier Approval Program

I'm trying to create a more robust supplier approval program and need some guidance. We've been a food manufacturer for over 20 years and have 500+ ingredient suppliers. Our ingredient types range from IQF vegetables & proteins, to cheeses & other dairy products, to dry goods.

We are in the process of requesting third party audits, certificates, and corrective actions from all of them.  This task is monumental espescially with the lofty goal of actually trying to read everything we get back.  I know the quick glance and a gut feeling are not going to cut it with FSMA.  Some aren't willing to share their audit and just send the certificate.  Do I accept this?  What are my options? 

My main quesion is what are people using for accept/reject criteria when approving suppliers? 

Thanks in advance!

I ask for a 3rd Party audit, Letter of Guarantee, and Certificates of Analysis for each PO ordered. If a supplier doesn't send me the full audit, the Certificate is OK.

Reading it all is a PITA, but I don't go over each with the magnifying glass, I look for scores, what their minors were on and go from there.

I hope this helps!