'If you say you're ethical, you have to back it up'

Oatly is a company which makes a range of milks out of oats. Since its products are plant-based, rather than animal-based, it says this makes it an environmentally ethical business. This is a big selling point with millennials, says CEO Toni Petersson.

But, he adds "if you're going to be ethical, you need to back up every claim that you make".

Video Journalist: Jeremy Howell

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