Be it in spreads, cheese sauces or atop gratins – yeast flakes, with their slightly nutty and cheesy aroma, are touted in many recipes as the ultimate way to get an umami kick without harming an animal. Looking like a mix of oat flakes and brown sugar, they can be used as a cheese substitute, as seasoning and to bind liquids. But what are yeast flakes? They are made from yeast fungi, usually baker’s or brewer’s yeast, which are cultivated on molasses or grain. This produces a liquid yeast that is sprayed onto rollers, dried and then ground into coarse flakes. But there’s no need to worry about…