Fining agents, use

Fining is a winemaking technique used to enhance sensory or clarity properties of the wines. Common fining agents used with North Coast white wines are bentonite (a clay), casein (milk protein), gelatin (animal protein),... 

Fining Agent Used Fining Agent Level (mg/L) Folin-Ciocalteau mgA. GAE) Gallic Acid Catechin Epicatechin t-Caftaric Acid CaffeicAcid Malvidin-3- Glucoside A... 

Antioxidant Activity towards Human LDL. At equivalent total phenol levels (by the Folin Ciocalteau method), all samples had similar activity at 10.0 pM where inhibition was generally above 95%. At 20 pM GAE all wines inhibited more than 99% of LDL oxidation regardless of the fining agent used. However, the wines had very different antioxidant activities at 5.0 pM (Table IV). The antioxidant activity at 5.0 pM GAE increased with all fining agents and dramatically with PVPP and bentonite. Because the antioxidant activities were compared after dilutions to equivalent total phenol levels, it is important to note that the data shows which samples of phenolics have the most potency at the same concentration, not which sample has the highest antioxidant concentration. 

Lysozyme may also influence protein stability in white wines. Thus, fining trials should be conducted prior to bottling wines treated with the enzyme. Although evidence is lacking, utilization of lysozyme may have an indirect sensory impact on palate structure similar to that of proteinaceous fining agents used in red wines. 

Incipient hazes may not be removed at all by simple filtration. An array of fining procedures have been developed to achieve stable clarity in such cases. Fining agents ate substances that ate or become insoluble in wines, and, as they precipitate, adsorb or coptecipitation incipient sources of cloudiness. Ptopedy used, the fining agents themselves ate not retained in the wines and thein effect is subtractive rather than additive. 

Antimony trioxide and sodium antimonate are added to specialty glasses as decolorizing and fining agents, and are used as opacifiers in porcelain enamels. Antimony oxides are used as white pigments in paints, whereas antimony trisulfide and pentasulfide yield black, vermilHon, yeUow, and orange... 

The small amount of mercury(I) chloride in suspension has no appreciable effect upon the oxidising agent used in the subsequent titration, but if a heavy precipitate forms, or a grey or black precipitate is obtained, too much tin(II) solution has been used the results are inaccurate and the reduction must be repeated. Finely divided mercury reduces permanganate or dichromate ions and also slowly reduces Fe3+ ions in the presence of chloride ion. 

Sami-Manchado, P. et al.. Analysis and characterization of wine condensed tannins precipitated by proteins used as fining agent in enology. Am. J. Enol. Viticult., 50, 81, 1999. 

The other abrasive agents used are tin oxide, chromic oxide, sand, carbides (silicon carbide and boron carbide), zirconium silicate, zinc oxide, garnet, rouge (fine red powder of iron oxide), kieselgurh, tripoli, magnesium oxide, hydrated silica etc. 

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