Chill filtering

Chill filtering is a method in whisky making for removing residue. In chill filtering, whisky is cooled to between -10 and 4 degrees Celsius (often roughly 0) and passed through a fine adsorption filter. This is done mostly for cosmetic reasons – to remove cloudiness, rather than to improve taste or consistency.

Method

Chill filtering works by reducing the temperature sufficiently that some fatty acids, proteins and esters precipitate out so that they are caught on the filter.^[1] The chillfiltering prevents the whisky from becoming hazy when in the bottle, when served, when chilled, or when water or ice is added. However, as this only happens at an alcohol content below 46 %abv, stronger bottled whisky is non-chill filtered or unchill-filtered, as the spirit will generally remain unclouded at this alcohol level.

Controversy

The merits of this method are disputed, opponents^[who?] claim that it diminishes the flavour of the whisky. As such, some distilleries pride themselves on not using this process, for example, the Aberlour Distillery's distinctively flavoured A'bunadh whisky or Laphroaig's Quarter Cask bottles are not chill-filtered.

Some whisky bottlers produce whiskies that are not chill-filtered, reportedly due to the reduction in flavour compounds that chill filtering produces. Skipping the chill filtering step can also reduce production costs.

See also

• A'bunadh (a Speyside single malt Scotch whisky that is not chill filtered)
• Booker's (a cask strength Bourbon whiskey that is not chill filtered)
• Laphroaig (an Islay Scotch whisky which has a “Quarter Cask” single malt expression that is not chill filtered)

References

1. ^ "Chill Filtering, Whisky". thewhiskyguide.com. http://www.thewhiskyguide.com/Articles/Chillfiltering.html.