Production Guide: Fining Agents Defined

What is a fining agent?

Fining is a process in which a winemaker adds a processing aid to the wine to remove some unwanted component in the wine. Processing aids are “substances that are added during processing but remain at undetectable or insignificant concentrations in the finished product” (Waterhouse, Sacks, and Jeffery 2016). Unlike “ingredients,” processing aids do not remain in the finished product. Since most fining agents are removed intentionally or through natural wine processing, they are grouped into the “processing aid” category. However, the use of some fining agents may become restrictive for wine marketing purposes (e.g., vegan status, Kosher certification) or can cause issue with some wine consumers (e.g., residual proteins that may result in an allergy). Both of these points has contributed to industry interest in plant-based fining agents as alternatives to animal-based fining agents (e.g., gelatin).

Though we often discuss fining agents as targeting a specific component in the wine, most are somewhat unspecific. This means that if the substrate that the fining agent prefers to target is not present in the wine or present at significant concentrations, the fining agent may attach or interfere with other wine components that are present.