Just an idea: Could they have been told to find a tea with the flavour of a specific fruit and at the bottom of the cup is the name of the fruit written so that the judge will recognise it?
Maybe it's not even written in English but in Hindu, to make it harder for the racers to remember what they have already tasted.
As for the tea having different flavours that's obvious of its colour. In many fotographs we see at least three different shades ( dark tea, yellow and orange coloured tea).