Chill filtering is simply a method in the manufacture of whisky employed to remove fatty compounds and proteins from the spirit before bottling. The distillate is chilled to right around freezing and passed through a filter where the undesired distilling byproducts are removed.
There’s been some controversy about the chill filtering process and its effect on the final product. Though designed to improve the clarity of the whisky, certain flavor components (such as peat particles) can be filtered out along with the rough stuff. As a result, many distillers have abandoned the practice.
Equally controversial, if not more so, has been the addition of E150a caramel coloring to the whisky produced by large brands to safeguard against potential inconsistencies in the color profile of the spirit. These topics remain a source of intense debate amongst Scotch enthusiasts. Fortunately, it’s never been easier to find a dram that perfectly suits your palate. Chill filtered and color corrected? Fine. Non-chill filtered and au naturel? Great. Straight E150a down the hatch? Too far.
The point is, no matter which side of the argument you fall on, you’ll never have to worry about an empty glass. Happy sipping.