Indianapolis’ metropolitan area is home to 23 breweries. And a dozen more plan to open this year. Head an hour or two away from I-465 and you can find many more brewpubs, microbreweries and taprooms. Meanwhile, national mega-producers increasingly offer seasonal and limited selections. But, as business booms and some worry about an oversaturation in the specialty beer market, for the beer-maker who actually gets his or her hands dirty with hops, malt and wort, it all comes back to the delicate alchemy of fermentation.