In Plant Based Promises, foodie, researcher and broadcaster Giles Yeo looks at the science behind plant based diets and the increasing number of plant based products appearing in supermarkets and restaurants. The market for plant based products could be worth $162 billion in the next ten years and Giles asks how sustainable and healthy the products are and the role they play in decreasing the world's carbon footprint.

Globally food production accounts for about 30% of greenhouse gases. In the UK we eat over six times the amount of meat and more than twice the amount of dairy products recommended to prevent the global temperature increasing more than 1.5 degrees C, after which extreme weather events become more severe. But eating less meat and dairy means new protein sources from plants are needed and how easy or practical is it for people to change their diets? Veganuary, where people pledge to go vegan for the month of January show that people are willing to change what they eat for a variety of reasons including animal welfare, sustainability and health.

In programme one Giles, an expert on food intake looks at some of the foods being developed to replace animal based foods and looks at alternatives to the iconic cheeseburger. Giles meets biochemist Professor Pat Brown founder of Impossible Burgers, a Silicon Valley start up making burgers from genetically modified yeast to replicate the taste of meat.

But from high tech to the artisanal, sisters Rachel and Charlotte Stevens missed eating cheese so much they are now making cheese alternatives using traditional moulds, cultures and aging techniques while replacing dairy ingredients with nuts.