i guess vaccum packing might work, but i really dont know. most people underestimatea dogs nose, they say that if you put it in coffee or vicks vapor rub the dog wont smell it. Well I'm almost positive they're wrong. Nothing can really throw the dog off, the dog can seperate the two smells. I've been studying the senses for quite some time, and i'll just say it's pretty damn hard to throw a good dog off.