A kiss is just a kiss — unless it’s a Hershey’s Special Dark Chocolate Kiss. In which case, pucker up for a mouthful of PGPR. PGPR, which began showing up on the ingredient list of drugstore chocolate several years ago, is short for polyglycerol polyricinoleate, a goopy yellowish liquid made from castor beans that reduces the viscosity of chocolate. Since 2006, big chocolate manufacturers such as Hershey’s have been replacing the expensive raw ingredient cocoa butter with PGPR in their recipes.