Packaging Design Eco Freshness Tag by Zeyuan Zhang This design targets and aims to solve a simple but tricky problem in life, that is how to tell the freshness of an egg. Customers may open a bad egg without pre-notice which can lead to either food poisoning or contamination of other ingredients. This issue enlightens the design of egg freshness tag which is a paper based chemical indicator reacts with carbon dioxide by the change of color to inform the freshness level. Different colors represent different grades of freshness, green for fresh, yellow for stale and red for bad.