Food Unwrapped returns with Jimmy Doherty, Kate Quilton and Matt Tebbutt revealing the secrets behind the food on our plates. Kate lifts the lid on the nation's favourite yeast extract, putting Marmite's latest TV advert - which claims that they can predict whether you love it or hate it - to the test. Jimmy finds out how plastic packaging is polluting the food chain with potentially global implications. And Matt undertakes his strangest science experiment yet: running across a pond of custard, which bizarrely helps solve the age-old mystery of how to get ketchup out of the bottle smoothly!