Britain consumes almost 220,000 tonnes of bacon every year. Chris finds out how mass-produced bacon can be made, while Gaby cooks up the posh stuff. Both types can have the chemical additives sodium nitrite and sodium nitrate added - but what do they do and could they be harmful?Matt reveals the role of slave labour in bringing food to the table. Matt meets two immigrant workers from Slovakia who were recruited in their home town to work in the UK. They say they were made to work for up to 70 hours a week and threatened with violence.Chris visits a butcher to learn the importance of storing and preparing cooked and raw meat separately to avoid cross-contamination. He also demonstrates how washing a raw chicken under running water can result in campylobacter being splattered across work surfaces, the wall, nearby food and utensils. Campylobacter is present in 65 per cent of raw chickens in the UK and it can be really dangerous, with 110 people a year being killed by it.In Oxford, food inspector Richard visits a hairdressing salon which is selling food and drinks outside its premises. There is no handbasin, no fridge and the wooden work surfaces are impossible to keep clean. And in Newcastle inspectors Paula and Caroline visit a kebab shop where they discover a boiler has broken down, which means the staff can't wash their hands properly.