It is my understanding that the "lemon oil" prized for protecting the
finish on wooden furniture, etc., comes from lemon grass, which is also
used in Tai cooking.  I have some growing in my backyard for the latter
purpose.  Commercial firms pushing pseudo-lemon oil products generally
put some perfume into the polish to make it smell like lemons, but check
the label to make sure the real thing - lemon grass oil - is in the
product for really good wood finish.