The nation’s brewpubs are keeping pace with production breweries in sheer diversity of styles and audacity in pushing the envelope, brewing up sours and barrel-aged beers.

This big, delicious sipping beer with a warming and lingering alcohol glow can be thought of as a dark, “imperialized” version of a hefeweizen.

Some of the best sour beers in the world are created by master blenders instead of master brewers. And yet you can’t take some classes and suddenly become an expert blender.

Brewers often fall silent when asked for advice on blending, not so much because they aren’t willing to share ideas, but because it’s so difficult to get started.