Time to empty out that big kitchen box. We are not performing science fair experiments in there are we? Empty and toss the expired foods, I guarantee they are lurking in there. Sanitize the drawers and shelves. Deodorize the inside walls with all-purpose cleaner and vacuum the coils behind, soak the ice cube catcher in baking soda.
When putting items back in, wipe them off so the old gunk doesn’t return. Organize the contents… condiments in the side door, dairy together, meat in the meat drawer, produce in the produce drawer and NOW… your fridge and food are fresh and that big box will run more efficiently.