The water in Kentucky is hard — meaning, it has a high pH and a high proportion of minerals, including calcium and magnesium. These elements are optimal for distilling. The yeast in bourbon adores those minerals. They aid the fermentation process and create the distinctive, crisp Kentucky bourbon we know and love. Even though bourbon can be made anywhere in the United States, over 95% of it is made in Kentucky. Bourbon's birth and heritage reside in Kentucky, but you may be asking yourself why. Ninety-five percent of the world's bourbon is produced in Kentucky, and if you're wondering if there's something in the water, there is.