Can there be an odor from a dishwash? We do not have an air vent on our dishwasher

Washed food not cleaned out at the bottom of the dishwasher. The dishwasher normally shares the sink trap and discharges above that trap.

You might try cleaning the dishwasher and to place a box of baking soda in there for a while, Maximize surface area. Dump some on a flat plate.