It may sound strange at first, but in addition to the sense of taste, the eyes also play a major role in deciding whether something tastes good or not. In contrast to the other senses, the sense of taste is very weak: while it is possible for us to distinguish thousands of colours with our eyes, we have the ability to distinguish only five flavours: sweet, sour, salty, bitter and umami, which roughly translates to meaty, a natural flavour enhancer, which is found especially in tomatoes, cheese, and meat. But as already mentioned, the sense of taste does not only rely on the tongue, but also on the eyes. For example, yellow, orange, and especially red food is considered sweeter than food of other colours. Even professional wine connoisseurs have been fooled in the past. When French researchers offered them white wine dyed with red food colouring, nine out of ten professionals could not distinguish it from ordinary red wine.