Trigger to audit table changes
You can catch values for every inserted column in a row and save them into the table where you save other audit data.

There are third party tools, such as ApexSQL Audit, that create such triggers, captures data (for UPDATEs both old and new) and shows reports.

When a row is inserted into a table with the following columns:

 

All column values are shown as separate columns



You can find more useful info here: Auditing triggers in SQL Server databases

Disclaimer: I work for ApexSQL as a Support engineer