FINING!

Fining \fine-ing\ vb : to make free from impurities.

 

A typical white wine regimen:

Post Harvest - Acidulate for pH correction.

Winter - Cold stabilize/reduce acidity.

Spring - Heat stabilize with Bentonite. Reduce harsh tannins & clarify with Gelatin & Kiesolsol.

Summer - Fine tune mouthfeel with Casein and/or Isinglass. Filter & Bottle. Enjoy!

A typical red wine regimen:

Post Harvest - Acidulate for pH correction. Fine with Gelatin to reduce excessive tannins.

Winter - Cold stabilize/reduce acidity.

Spring - Fine tune mouthfeel with Casein and/or Egg Whites.

Summer - Filter & Bottle. Enjoy!

One assumes that you are monitoring SO2, bringing to recommended levels after the end of M/L and maintaining through fining, filtering and then bottling.

BENTONITE: Aluminum Silicate is used primarily to achieve Heat Stability. While it will remove some hazes, its prime use is to remove unseen protein fractions that are unstable at wine pH. Hazes that remain after using 2 lbs./1000 gallons will respond better to a gelatine-kiesolsol treatment.

Dose: 1/2 tsp./gallon = 3 lbs./1000 gallons

SPARKOLLOID: This is a very useful haze removing fining agent. It is a long-chained polysaccharide in an agar base. Possessing a slight positive charge, it forms a microscopic spiderweb, trapping fine colloidal and negative charged particles as it settles. Also tends to collapse bentonite, compacting the lees.

It is simmered in water for 20 minutes to dissolve the agar and is added warm.

Dose: 1 tsp./gal.

KIESOLSOL: Soluble Silica Gel. Has a negative charge which attracts positive charged proteins and tannin-protein complexes. This coagulative process is rapid, uses little silica, and results in compact lees. Add Kiesolsol and then gelatine to remove some hazes. More common is to remove excess tannins with gelatine, followed by Kiesolsol to remove excess gelatine. The resultant coagulant then fines the wine.

Dose: 1/2-1 ml./gallon, with 1/4-1/2 lb. gelatine/1000 galllons ( 1/4-1/2 tsp./5 gallon ).

POLYCLAR/PVPP: Microscopic, insoluble nylon that binds with some phenolic compounds. Can remove color precursors, preventing enzymatic browning/pinking in whites. Not as effective after the fact. Also, may clean-up an imperfect wine’s odor/flavor. Can remove anthocyanin (red) color, as in too-red blush wine. Useful for reduction of bitterness (monomeric tannins only).

Dose: 1/2-6 lbs./1000 gallons ( 2 tsp.-8 tbl./5 gallons ).

GELATIN: A protein that attracts tannins, reducing bitterness/astringency. White wines that have a slightly harsh or bitter flavor can be smoothed out with a very small amount of gelatin, followed by kiesolsol.

Hazy whites that have resisted other clarification agents like bentonite will fall crystal clear with gelatin.

Dose: 1/8-1/4 lbs. gelatin/1000 gallons ( 1/8-1/4 tsp./5 gallons ), followed by 1/2-1 ml./gallon kiesolsol.

Tannin was formerly used to settle gelatin, but kiesolsol is preferable. Gelatin will not coagulate and settle out in whites without kiesolsol.

In reds, use gelatin for clarity at levels of 1/4-1/2 lb./1000 gals. For reduction of bitterness in young reds, use 1/2-2 lbs./1000 gallons.

Being rather non-specific, gelatin is often too harsh a treatment for older reds coming out of barrel, so casein or egg whites may be preferred.

To prepare, make a 1% solution (1 gram/25 ml. cold water). Allow to expand. Add hot water to 100 mls. to dissolve.

CASEIN: Potassium Caseinate can improve both flavor and color in slightly oxidized whites. It is more gentle on reds when used close to bottling to reduce astingency. Can also reduce oakiness and slight microbial off-odors.

Dissolves in water, though not easily. Mix 1 volume in 9 volumes water for a few hours. Dilute this paste to be a 1-2% solution. Stir until dissolved. Do not heat. Store in freezer.

Dose: 1/8-1/2 lb./1000 gallons ( 6 grams/5 gallons ). Not over 1 lb/1000 gallons or may impart a milky flavor.

SKIM MILK: A home source of casein. Use powdered skim milk, not whole milk. Caseins flocculate quickly with the wine’s acidity, tending to clump before they can react with the tannins. Best to inject in a fine stream with a syringe or baster. Or, add while racking.

Dose: 1/2 pint skimmed milk/5 gallons. Or, 10 grams powdered skim milk/5 gallons in a bit of water.

EGG WHITES: The albumin attracts older, long-chained tannins, slightly reducing astingency and improving mouthfeel in red wines only. Salt is added to solubilize the globulin, clarifying the mixture. It clumps rapidly, so follow the addition advise of casein.

Dose: 1/2 egg/5 gallons = 5-6 eggs/60 gallon barrel. Some use a "pinch" of salt. Or, 2 times the volume of salted water. Salted water = 10 grams salt/1 liter water.

Just wisk the mixture. Do not beat to a fluff.

For dried egg white, use 2.5-4 grams/5 gallons with a bit of warm water.

At The Daume Winery, I use egg whites, a pinch of salt, a wisk and, of course, a copper bowl. Add while stirring the barrel, avoiding aireation.

ISINGLASS: Collagen from the air bladder of sturgeon, "Isinglas is to whites what egg white is to reds". It reacts with older, long-chained tannins to gently improve mouthfeel. Older forms of the stuff were very hard to dissolve and smelled strongly of fish. I have an English form from James Vicker called Drifine that is easy to prepare and is much less smelly.

Dose: 10-30 miligrams/liter.

These fining agents are very useful tools to achieve brilliant clarity as well as a more pleasant and balanced mouthfeel.

Always test first to determine the desired effectiveness and the correct quantity to use. Too much added can take too much out of the wine and may leave excess fining in the wine.

It’s important to understand phenolic extraction and developement as the wine ages. Phenols include tannins and color pigments. They come mostly from grape skins, as well as seeds, stems and barrel oak.

As wine ages, phenols link togather, becoming "poly" phenols. Young tannins may taste too coarse. With age, a pleasant dryness/astringency may remain.

Also, remember from the previous discussion of "co-pigmentation" that there is an equilibrium existing between tannins and color pigments. Removal of tannins with protein fining agents can disrupt this equilibrium. The result can often be loss of color stability. It is highly recommended to fine for tannic astingency early in the game before your wine is over 4 months old.

 

Reference Books: (All books are available at The Home Beer/Wine/Cheesemaking Shop)

Ough: "Winemaking Basics"; AWS: "Complete Handbook of Winemaking";

Wagner: "Grapes into Wine"; Lundy: "Homemade Table Wines";

Fessler: "Guidelines To Practical Winemaking"; Vine, etc: "Winemaking, From Grape Growing to Marketplace";

Margalit: "Winery Technology & Operations";

Zoecklein, etc: "Wine Analysis & Production"; Margalit: "Wine Chemistry";

Boulton, etc: "Principles & Practices of Winemaking"