What are the three categories of common fining agents?

• A. Remove unstable proteins; Remove phenolics; Remove color and off-odors
• B. Remove unstable proteins
• C. Remove phenolics (bitterness)
• D. Remove color and off-odors

Answer: (D)

Fining agents are used to remove specific types of unwanted compounds from wine, improving stability, clarity, and balance. There are three common targets: unstable proteins, phenolics, and color and off-odors. Unstable proteins can cause haziness, so protein-based fines help remove them. Phenolics—such as tannins and related compounds—can contribute bitterness and astringency, so fines that bind or remove these substances are used. Color and off-odors come from pigments and volatile compounds that alter appearance or aroma, and fines like activated charcoal or PVPP help address those issues. The complete three-category description best fits how fines are routinely described, whereas options that mention only one or two targets don’t capture the full scope of what fins aim to remove.