Shoppers have been confused by a series of secret letters and numbers printed on food packaging and have been asking what the hidden meaning is. One shopper, Naomi Willis, posted in the Facebook group Reduce Your Supermarket Spend to ask what the codes could mean.
Naomi runs the group with her husband Ricky - better known as Skintdad.
She wrote: "For anyone who works in Tesco, is there a specific name for these codes (A21, F22, D4 etc)? My understanding is that they represent a month and day of the week to help with product freshness."
