One concept/inspiration suggested the use of baacodes to link back to the animals; For your idea I'd suggest adding in Moovies - scan your milk carton to get a live web cam showing the cows that your milk came from. I was at a dairy north of Brisbane over Easter with my kids (Maleny dairies) They could probably trial this (perhaps with some help from the Queensland government?) since they are an independent producer who do their own packing/distribution and are proud of their quality products.
Great screen shots Sina. Ive got a smart phone, but would I use it when shopping? Maybe not me as I rush through finding what i want, but this would be great to educate and distract my young kids in store! I'd suggest ensuring the content is great for young kids as well as adults.