Each bag was secured with a different color twist tie. The old one was blue. The new one was white. Seeing the two colors made me think of the 'bread tag code' I learned about from a friend a while back. Basically, each day has a different color twist tie to help you figure out what day the bread was baked.
The system was set up to help stores identify which bread is fresh, which is getting old (so it can be put on sale), and which is out of date and needs to be removed from the shelves. As a rule, unless a stocker has missed pulling an old loaf you should only see two tag colors on the shelves at any one time.
There are a lot of online articles that give a definitive twist tie color schedule, but Snopes says there's no industry-wide standard for color coding. Each manufacturer is free to come up with their own system.
Five years ago today: Turkey Trivia