The TTB with its Beverage Alcohol Manual, BAM, defines 35 different types of American whiskies. Before the whiskey boom of the past 10 years only a handful of these were actively produced. Between all of the craft distilleries and NDP’s, Non Distilling Producers, introducing new brands we are now seeing many more of these 35 types being introduced. An example is class type ‘Whisky distilled from Bourbon Mash’. Whenever you see a ‘distilled from XYZ mash’ statement on a label, you know the whiskey has been aged in a used barrel. For my money, I want the genuine article so therefore I purchase Straight Whiskey. The word ‘Straight’ carries much legal meaning; it means the whiskey has been aged at least 2 years in a new charred oak container, with an exception for only Straight Corn Whiskey. It also means no flavors or coloring has been added and that it is the product of only one state. A few years back, I put together this spreadsheet based on the CFR’s and the BAM showing the differences between the most common whiskey types.
link to google sheet – Basic American Whiskey Types
A side note about our spirits labeling laws. The BAM is the TTB’s simplified interpretation of the actual labeling laws found in the CFR’s. If you want to read the BAM here is the link BAM. The TTB also writes regulatory rulings and other guidance such as FAQ’s.