you can check if audio if lossy using frequency analysis and spectral analysis.
i'm afraid your shit ton of cds won't be of much interest though. unless you've got some things that can't be found anywhere else.
it's just that sources without the extra cd-r in the lineage will be preferred, as well as sources with a known source and lineage. considering how you're not even sure if a cd is mp3 sourced for some of your cds, i can imagine source and lineage are a question mark too.
check out these posts/threads - maybe you have some of these: