Is there any actual difference in the chemistry or components of a Kopi Luwak coffee bean, and a more traditional coffee bean? If so, what are those differences?
Actually they recently came up with a reliable test for civet coffee. Apparently a great deal of supposedly authentic stuff never actually traveled through the bowels of a cat.
According to the abstract, the levels of citric acid, malic acid, and the inositol/pyroglutamic acid are so much higher in kopi luwak that their ratios can be used to validate mixes with other beans where the proportion of kopi luwak is 50% or greater.
I think that coffee from the Civet has lower levels of both nutritional chemicals and psychoactive (including caffeine) compared to normal coffee beans, because in the Civet most of it has been digested.