Artist Ko Yang  has designed a milk carton, titled Expiry Date, that changes color as it nears the expiration date. The carton starts out as white and slowly grows in to a cheese like orange color in order to alert the owner of the freshness of the milk. This is a brilliant way to let the consumer use food without wasting it, however, it is not nearly as appealing to the seller.

Check out the different phases by clicking the link below.