A few ideas.
If to asses change you are using just time, you could use 'find':
to get files modified in the last 5 minutes.
If as a reference you need another directory, you may use a dry run of rsync:
Another alternative would be to constantly watch the directory using inotifywait (from inotify-tools):
rsync -av --dry-run source/ destination/
Does that help?
while inotifywait -r -e create,modify,attrib,move,delete /path/to/folder
echo "A file or directory was modified."