The first time I ate sushi, I did not vomit even though thinking about sushi made me retch. The reason was none other than my ignorance: I totally ignored that in the salad I was eating there were pieces of sushi, so that salad seemed right to me. However, the second time I ate that salad, already knowing that there was sushi, I suffered arcades. (Now I love sushi, don't suffer).
This little anecdote exemplifies to what extent what we think influences the taste of things. Previous expectations powerfully influence the vision of subsequent events, including those that fall within our taste buds. This effect also occurs in beer consumption.
In an experiment conducted at MIT by the psychologist Dan ariely Two beers were served to customers in a Boston bar. The first was a Budweiser, and the second a Budweiser with two drops of balsamic vinegar for every ounce of beer.
The customers tasting was blind: they did not know what brand of beer they were consuming. Many customers chose beer seasoned with vinegar.
However, if the client was informed that vinegar had been added vinegar before beer B, then people wrinkled their noses when tasting beer B and preferred A, the original Budweiser.
What seemed to happen is that if you told a person that what he was going to try was probably going to taste bad (and beer with vinegar doesn't sound good at all), then he is likely to notice a more unpleasant taste. Previous expectations influence the taste. As explained by himself Ariely in his book The traps of desire:
If, upon arriving at this part of the book, the reader is considering setting up a new beer company, especially one that specializes in adding a few drops of balsamic vinegar to beer, you should first consider the following aspects: 1) if people read the label, or find out the ingredient, most likely you will hate your beer; 2) Balsamic vinegar is currently quite expensive, so it is possible that, despite making beer taste better, the investment is not worth it; I better make a better quality beer.
Expectations influence our perception of taste so much that, in reality, most people seem to like Pepsi more than Coca-Cola, but only if you don't know what you're taking before. If you know, then you prefer Coca-Cola. You can read the full experiment in Why does Pepsi sell less than Coca-Cola if Pepsi tastes better for most people?