Berkley makes some different scents you can apply or put on/in with the plastics. Walmart usually has some scent stuff you can shoot into the plastic bag also.
One of the easiest things you can do for scent that won't just wash off is take some really fine salt like popcorn salt and add a little to the plastic before you shoot the plastic. Then the salt is infused into the body.
Fine popcorn Salt & Anise oil are simple things picked up at a grocery store that work fairly well.
