To put it broadly, this is about guilty pleasures, that are not accepted in one's social environment. This excludes more serious topics (politics, religion, legal/moral questions etc.). Think of movies, music, sports teams, books and the like.
Furthermore, I refrain from using actual examples to avoid a discussion about them ("But he is right! They are the worst team ever!"). This could be changed upon request, but I don't think it's necessary.
I enjoy music by band "so-and-so"*. Now I have a nice talk with "Bob". Bob is a good acquaintance of mine, and also a real music connoisseur. Somehow, the discussion strays away a bit from positive topics, and he notes the decline in musical taste. His prime example is, you guessed it, "so-and-so". So he rants about them, their inferior music, lack of talent, cheesiness etc.
I listen to him patiently. He can't know that I like them. And I get a strong impression that he couldn't even imagine it in his wildest dreams, since he knows that I like the music he approves of. And now, that he finished, he asks me after my opinion on them.
I don't want to lie. On the other hand, his critique is spot on, and I don't have rational arguments to support my stance. The ensuing situation is rather awkward.
*Not an actual band, although a quick google search showed, that there are bands of that name, but spelling differs slightly. But I don't know them.
How to avoid, or at least, alleviate such an awkward situation? How to react to Bob to avoid as much of an embarrassment (for both of us) as possible?
Please note that Bob's perceived reaction to my confession would not be laughter, but rather an embarrassment himself (for offending me, in a way). And my concern is not, that he would think less of me (after all, it is about rather trivial matters), but that it would ruin the moment.