Which method is typically used to achieve microbiological stability in wine?

• A. Sterile filtration
• B. Sorbic acid + SO2 addition
• C. Velcorin (DMDC)
• D. Pasteurization

Answer: (A)

Sterile filtration is used because it physically removes microorganisms from the wine just before bottling, preventing any microbial growth in the bottle. By passing the wine through very fine membranes (capable of retention down to yeasts and bacteria), you achieve microbiological stability without exposing the wine to heat or adding stabilizers that could alter aroma or flavor. This keeps the wine’s sensory profile intact while ensuring it remains stable during storage.

Alternative methods exist but are less universally preferred. Sorbic acid with SO2 can inhibit spoilage organisms but may cause off-flavors in some wines and isn’t as universally reliable. Velcorin works well but adds cost and may affect aroma. Pasteurization effectively kills microbes but can change color, aroma, and structure, which is undesirable for most wines.