Beetroot and smoked mackerel

Tonight we cooked for our friends K and J, who are vegetarian (+fish) and trying to avoid animal fats. For starters I tried processing plain cooked beetroot with smoked mackerel plus freshly ground cumin that I'd heated in a dry pan. That's all. Nothing else. Sprig of parsley on top for show. It was really lovely with some poppy seed biscuits. The colours are not right in the blip, thanks to the lighting in our kitchen, but I don't seem to be able to correct them in Paintshop. I managed to make it an alarming bright blue without trouble, but a decent beetroot colour eludes me. any hints gratefully received!