Chateauneuf-du-Pape is one of many new wine brands that have started using the new tetra packaging. This packaging replaces glass bottles and is more easily transported. Other notable wine brands that use tetra packaging include Quarter Trebbiano, Sangiovese Rose, and Sangiovese.
A Tetra Brik is a carton produced by the Swedish packaging company Tetra Pak. The Tetra Brik is specifically designed for cold beverages. The noun Tetra Brik is a proper noun, the name of a specific product. Proper nouns are always capitalized.