Our friends at PCCA have a blog post you probably want to check out: "Changes to the Paycheck...
Raw material substitution?
The new blog post from Gus Bassani, PCCA's chief scientific officer, explains "Why Brand and Generic Substitution Is Not the Same as Raw Material Substitution" — definitely worth a read.
You already know to get your ingredients from reputable repackagers and manufacturers, but Bassani explains that substitutability is a bit of a different creature. "USP specifications," he explains, "may not cover every important aspect of a raw material."
Check out the whole story.