One taste can undo a judgement built entirely on looks. You had decided, quite confidently, from appearance alone, and a second of actual contact with the thing dissolves it. The speed of the reversal shows how thin the original judgement was, however certain it felt.

It is worth collecting these experiences on purpose, because they are cheap lessons in the unreliability of first impressions. Eat the unattractive dish. Read the badly designed book. Talk to the person who looks like nothing to you. The correction rate is high enough to be interesting, and the habit generalises to situations where the cost of getting it wrong is considerably larger than a meal.