Fining is a method of clarifying wine by adding a coagulant to the must and letting it settle to the bottom. Some common fining agents are egg whites, bentonite, sparkalloid, and gelatin.
Notes from the winemaker: In my opinion fining is always remedial. My objective in commercial production is never to have to fine a wine. The questions of whether or not to fine a particular wine, what to use, how much and when require the application of professional expertise and so are best avoided altogether. I see part of my role as identifying protocols and methods to use with ProVina-sourced grapes that result in wines that don't require fining. But there are going to be WinePod wines that will benefit from a bit of remediation. Over-oaking and oxidation can be somewhat ameliorated with a combination of milk and egg whites. Excessive harsh tannins can be removed with egg white and/or gelatin. How to provide the professional expertise to assist the WinePod user base in making fining decisions is an open question at this time.
More notes from the winemaker: Online literature citations suggest that wheat gluten can be used as a fining agent for wine (indicating that it precipitates well) and the FDA has recognized its use as GRAS, but gluten protein is soluble at pH 2.0 and may be at least slightly soluble at wine pH and alcohol content. TTB has proposed rulemaking for allergen labeling in concordance with the Food Allergen Labeling and Consumer Protection Act of 2004 that would mandate listing on the packaging any wheat products used in wine processing.