Overview: Sian Williams and Stefan Gates continue the investigative documentary lifting the lid on supermarket food, this week focusing on meat. Sian finds out how little meat there is in a budget sausage - and all the other ingredients shoppers are paying for instead - and discovers how the brain is fooled into believing supermarket farm brands are higher quality than their budget versions. She also sees first-hand the conditions in which chickens are reared, and Stefan investigates how the dangers of poultry contaminated with potentially deadly bacteria.