Expiration Notification of Lot Number Items

We sell a variety of lot numbered items that have expiration dates.  Some customers want to know if the items they have purchased from us have expired (since they are rarely consumed).  I am trying to create an alert via a saved search that will look at fulfillments and notify sales reps if an item their customer purchased is expiring.  I tried using a transaction saved search but I don't see expiration dates anywhere in the criteria.  Any help would be appreciated.

Thanks,