What a fast-food chain discovered: during "routine" mystery client visits, shoppers rated some products as too salty, while other scenarios did not pick up this trait. Thanks to the mystery programme we were able to discover that one particular product, once heated, became too salty, delivering a flavour out of line with the standard quality. The solution proposed was to produce two different versions of the sandwich with two different amounts of salt, to be used in the two cases: a sandwich to be heated, and a sandwich to be eaten at room temperature. At that point the shoppers were trained to assess this difference and, in a dedicated cycle, first ordered the sandwich hot and then asked to have it at room temperature, verifying that the staff replaced the sandwich.
