Why do our brains go crazy for the melted cheese on Philly's iconic cheesesteak? What is it about scrapple’s crispy fried goodness? How does surface-area-to-volume ratio make the roast pork sandwich more delicious? This week, we take a road trip to the City of Brotherly Love to feast on some classic Philadelphia fare. We also learn about the science of appetite with a researcher at the Monell Chemical Senses Center in West Philadelphia. It's hard work, but we're making the big sacrifices for science.

This episode originally aired on February 23, 2015, and July 8, 2019, and was produced by Dan Pashman, Anne Saini, and Ngofeen Mputubwele. The Sporkful team now includes Dan Pashman, Emma Morgenstern, Andres O'Hara, Kameel Stanley, and Jared O'Connell. This update was produced by Gianna Palmer.

Every Friday, we reach into our deep freezer and reheat an episode to serve up to you. We're calling these our Reheats. If you have a show you want reheated, send us an email or voice memo at hello@sporkful.com, and include your name, your location, which episode, and why.

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