Kraft Heinz has decided the "ketchup bottle of tomorrow" is going to be made out of paper.

The company says it's partnered with Pulpex, which describes itself as "a new packaging technology company with a single-minded mission to deliver sustainability through renewable packaging," to develop a Heinz ketchup bottle made out of wood pulp instead of plastic.

"Pulpex’s current data indicates the carbon footprint of Pulpex bottles is materially less than glass and plastic on a bottle-by-bottle basis," Kraft Heinz says in a press release. "Once used, they are also expected to be widely and readily recyclable in paper waste streams."

The companies will develop a prototype to "assess performance"—by which they probably mean they want to make sure the wood pulp won't leak or impart unwanted flavor—of the Pulpex bottle. They will ship these bottles to consumers if the prototypes pass mustard... erm, muster.

Kraft Heinz says its partnership with Pulpex "aligns with its goal to make all packaging globally recyclable, reusable, or compostable by 2025" and "will help Kraft Heinz achieve net zero greenhouse gas emissions by 2050." (Assuming, of course, the bottles work as intended.)