As you continue to read about whiskey, you're bound to run across these three criteria that aficionados have when it comes to evaluating the quality of their dram: authentic color, ABV, and the use of chill filtration. Some are so didactic about this that they feel that any hooch that's been colored, chill filtered, or isn't at least 46% should be tied to a stake and set ablaze.
Let's look at these separately before I weigh in with my opinion.
The reality is that most whiskeys aged for 12 years or less will come out pretty pale if they haven't spent a tremendous amount of time in a sherry cask. For a good example of what whiskey tends to look like, buy yourself a bottle of Ardbeg 10. The color is extremely pale. But holy shit, you'd be the wrongest shade of wrong you'll ever be in your life if you conclude Ardbeg 10 doesn't have flavor or character based on how it looks in the glass.
The reason why most “brown liquor” looks brown at all is through the use of a dye called Caramel E150. Also, Santa isn't real and most American settlers didn't enjoy a turkey-based relationship with the Native Americans who originally called this nation home. For an in-depth look at the chemistry and variety involved in E150, Whiskey Science has a great write-up.
Purists dislike the added color since it's simply low-grade deception; the colorant only exists to convince the consumer that their liquid is of a higher quality than it actually is. On the other side of the debate, blenders like Richard Paterson argue that people taste first with the eyes, and sampling a product that seems visually pleasing provides many of us with a positive first impression and allows us to focus more on the quality of the taste. The truth lies somewhere between marketing fluff and depthless cynicism.
By law, if you're going to call something whiskey—regardless of what kind of whiskey it is or where it comes from in the world—it needs to be at least 40% alcohol by volume. However, there are many consumers who flat-out refuse to buy anything that doesn't bat at least 46% ABV.
In general, as you increase the proof of the whiskey, you actually do get more flavor. Whatever malt you prefer, if there's a “cask strength” version (which typically means it's at least 55% alcohol, or 110 proof), you will get far more intensity.
Many purists take umbrage with an ABV of 43% or less, since it basically means that the distiller has added the water for you, thereby cheapening the product in the names of making their supply stretch just a tiny bit farther.
But logically, if most of us add some water anyway to kick the ABV down to 43% (or less!), is there any reason to make a fuss? In my opinion, even with a splash of water, a cask-strength version of a whiskey diluted to 40% will always be more intense than it's entry-level cousin that was bottled at the distillery at 40%. Chemistry tells us there should be no difference, but it's hard to fool the tastebuds.
Note, however, that there are a lot of powerhouse whiskeys that transmit huge flavor at 40%, and some whiskeys that become only more hot on the palate without any additional flavor when the ABV is cranked to monstrous levels. Additionally, how “hot” you perceive a whiskey to be varies from bottle to bottle even at an identical ABV.
A biggie, here.
The process of chill filtering is designed to create a more consistent product, distillers argue. Normally, when ice or water is added to whiskey, it becomes cloudy. This is 100% normal. Chill filtration makes it so whiskey has the same level of transparency and clearness when water is introduced. Like color additives, many distillers claim that consumers expect consistency in the product and by god, they're going to give it to them.
The issue is that the filtration is actually filtering out small bits of protein and esters that give any whiskey at least part of its taste. It's hard to quantify how much of a difference this makes, but the reality is that you are losing at least some amount of flavor.
Perhaps you can't quantify it, but the purists say that if you enjoy a chill-filtered whiskey, it'd be better to some degree if it had been bottled non-chill filtered (NCF). How much better? You'll never know, but in truth, neither do the most vocal critics.
I tend to be less dogmatic about these three things than a lot of spirits authors online. For example, the Dalmore 12 is colored, chill-filtered, and bottled at 40%, and I still think it's a wonderful dram with a unique flavor profile. I buy it often, and friends I've introduced to the Dalmore 12 have bought it themselves. By all accounts, boycotting Dalmore based on their distillery practices would have prevented me from enjoying what I consider a perfectly fine scotch. Same goes with Cragganmore 12, a Diageo product that's been chill filtered, artificially colored, and diluted to the legal minimum. The only problem? It's a powerhouse of a whiskey.
That said, I think that the above-mentioned drams are exceptions to the rule, and as such I do have a preference for a 46% ABV scotch with no color added and no chill-filtration. To me, those are signs that the distillery has tried to make something for me and guys like me, not the Average Joe.
When you see something cask strength, NCF, and NCA, it signals a craft product, not a mass-market commodity. The distiller has left it up to me to determine the level of dilution where I enjoy the spirit best, entrusts me to know what whiskey is supposed to look like, and has ensured that what's in the bottle is the most flavorful it can possibly be.
All things being equal, those are qualities that I like to support, but taken collectively it's not a hill I'm prepared to die on. Try a whole bunch of stuff and see where your own thoughts lie.