Couch odors are common, especially when you combine the amount of time spent on the sofa with the absorbency of the fabric. To keep the couch smelling its best, use deodorizing elements that pull out the odor without damaging the couch itself. Keep in mind that a lot of those commercial fabric refreshing and deodorizing sprays are filled with chemicals, so it is best to instead use more mild cleaning solutions.
Sprinkle a light layer of baking soda over your entire couch, including over and around cushioning. Let the baking soda sit for at least an hour, or even overnight when possible.
Vacuum over the couch to collect the baking soda as well as any loose crumbs that may be causing an odor.
Fill up a spray bottle with one part water and one part white vinegar. Spray this mist over the sofa lightly just as you would a fabric refreshing spray. Let the couch air dry and remember that there will be a slight vinegar odor for an hour or so until the scent fades away.