Oregon content creators Libby Cope and Jacob Arnold have sparked a viral trend by making butter during their trail runs. The couple discovered that heavy cream in double-bagged Ziploc pouches transforms into butter through the natural agitation of running. Their TikTok video showing the process has garnered over 2 million views, inspiring others to try the unusual combination of exercise and food preparation.

Cope, who runs the Instagram account @lib_claire, explained that the idea came from her love of high-quality dairy. After noticing how cream foamed when shaken, Arnold wondered if running with it would create butter. They found no evidence anyone had tried this before, so they experimented with different cream types, temperatures, and running conditions. Their most successful batches came from using higher-quality cream and running in 50-55 degree weather.

The science behind it is simple: cream is an emulsion where fat molecules separate and clump together when agitated, expelling liquid to form butter. The couple has refined their technique, using less cream and avoiding river stops that previously slowed the process. They've inspired others like Irene Choi, who made corn juice honey butter, and Lauren Lecompte, who attempted it during a snowstorm. For Cope, the trend represents a joyful return to running's simple pleasures.