Every Steam Disc carries and appID which can be found written in the .sis file on the disc. This is essentially an ID for the game included and having a tag among the general ID (ISBN, DNAS, etc) fields could be a good idea.
Included the SIS (Renamed to txt due to Github) for http://redump.org/disc/36660/ as to show a random example. Useful also since they can be compared to corresponding entry in SteamDB.
https://steamdb.info/app/22350/
Brink_disk1.txt