I really have no idea, but here's my current guess. From the page at: https://en.wikipedia.org/wiki/Melton_Mowbray_pork_pie#Melton_Mowbray_pork_pie https://en.

I really have no idea, but here's my current guess. From the page at: https://en.wikipedia.org/wiki/Melton_Mowbray_pork_pie#Melton_Mowbray_pork_pie https://en.wikipedia.org/wiki/Melton_Mowbray_pork_pie#Melton... Protection was granted on 4 April 2008, with the result that only pies made within a designated zone around Melton, and using the traditional recipe including uncured pork, are allowed to carry the Melton Mowbray name on their packaging So, it appears that a "pie zone" may be a "Protected designation of origin". https://en.wikipedia.org/wiki/Protected_designation_of_origin https://en.wikipedia.org/wiki/Protected_designation_of_origi... However, applying this to the context of the article barely makes sense. Perhaps the 1920s "pie zone" is what eventually evolved into the 2008 law?