Modify log text

We would like to modify the log text for certain change log activated on certain tables. For example, when we change employee rate, or customer credit line, e-mail is forwarded to email recipients but we have no clue which employee's rate or Customer credit record has been updated. The idea would be to select a few meaningfull fields to be added to the log text attached to email so as to have some idea of nature of changes.

Many thanks