Quinine adulteration and taste preference tests.

<p>A) Quinine was added to ethanol in weekly tests of quinine adulteration in a two-bottle choice paradigm (water vs. 20% ethanol+quinine). B) Quinine preference was determined in a two-bottle choice paradigm (water vs. water+quinine). C) An additional quinine adulteration test was performed in a subset of rats with a higher maximum quinine concentration. N = 12/group in A, B. N = 6-9/group in C.