What does 'louching' refer to in the context of spirits?

Louching refers specifically to the phenomenon where a spirit, particularly anise-flavored spirits such as absinthe or ouzo, becomes cloudy when water is added. This cloudiness occurs due to the solubility of essential oils and compounds found in the spirit, which precipitate out of solution when diluted. The louching effect not only alters the visual appearance of the drink but can also enhance its aromatic qualities, making the experience of consuming anise-based spirits more complex and enjoyable. The other options do not align with the term "louching," as they pertain to different aspects of spirit production and aging processes.