As the saying goes, you either love Marmite or you hate it. On one side are devoted fans who worship “black gold” and would pour it on their cornflakes if they could. On the other are those who hate its yeasty, bitter tang. I’m one of the latter: for me, Marmite has the taste of stale, acrid sardines and the texture of cold treacle. They say the best things for you often taste the worst – such as cabbage, lentils and green tea – but I’d need a lot more convincing before spreading Marmite on my toast.