If you have odors coming from your kitchen drain, I will assume you have a garbage disposal. What happens is food gets stuck to the underside of the rubber flaps at the entrance of the drain and, stuck to the sides of the drain. The remedy is simple - by a large baby bottle brush at the dollar store. Stick it down the drain and rub it against the sides of the drain and the underside of the rubber at the entrance. Pull it out slowly or black, nasty, smelly gunk will fly everywhere.
Once you've given it a good cleaning, run some dishwashing soap down the drain.