^^^^(red) - Was it "scientifically" validated or ?
No, absolutely not. During the Rabbi's first visit, he explained that the process would be nothing like a normal audit, and that much of what he was interested in couldn't be tested or measured - it came down to his experience/knowledge/interpretation. He also confirmed that this was why we'd found quite widely differing views amongst the different certification bodies with whom we'd spoken.
In the specific case of liquid grape products, his explanation was roughly:
Back in ye olden days, it was common practice to make an offering of wine / grape juice at the temple(s) of one's chosen deity/ies. But it would be wasteful to simply pour it out, so it wasn't at all unusual to pour the wine out of one receptacle as the offering, and then catch it in another for later consumption. This created a situation where, unless you knew the full history of your grape product, you had no way of knowing whether it had or had not been offered to the wrong god(s). The potential contaminant is therefore a spiritual(?) one, and that makes it "challenging" to test for removal of this by a cleaning process, or to analytically validate absence in a subsequent product...