The array of clarifying agents available include;
Activated carbon, Bentonite (wine grade), Casein and caseinates, Diatomaceous
earth, Egg albumen, Gelatin (low bloom), Isinglas, Kieselsols, Polyvinylpyrrolidone
(PVP), and Sparkalloid. Commercial combinations of some of these
are also available.
Fining agents work on the principle that all of the particles
responsible for the clouding or haze in a wine or beer
have an electrical charge. As an example gelatin has a positive charge
meaning that it can attract negatively charged materials. In binding to
the negatively charged materials the combined weight increases resulting
in settling to occur. In practice it’s usually necessary to have finings
agents of different charges added sequentially to the wine in order remove
the materials of various charges contained in the wine.
Positively Charged Negatively
Proteins which are not removed during post fermentation
settling, fining or filtering are small enough to remain soluble. These
have some effect on the wine flavours in terms of perceived body / mouthfeel.
Polyphenols may be considered as much more active over
time than proteins. They are susceptible to oxidation and polymerization
which will impact the wines aromatic and taste qualities. Polymerized polyphenols
are generally referred to as tannins. The simple flavanoid polyphenols
form the precursors or building blocks of tannins. These flavanoid polyphenols
can be divided into; anthocyanins, flavones and leucoanthocyanins/catechins.
Anthocyanins (red pigments) undergo colour change with
pH shifts. Flavones are yellow polyphenols similar to anthocyanins and
can undergo oxidation reactions leading to brown polymeric pigments.
The leucoanthocyanins and catechins have a similar structure. In red wines
thay may be present at 1-3g/L and a few 10th’s of a milligram in white
wines. These can vary from colourless, non-astringent molecules up to haze
forming, red coloured precipitates depending on the degree of polymerization.
Pinking is thought to be a side reaction of these leucoanthocyanins
due to conversion to flavenes through a slow hydration process. The important
part of this is that we can associate color changes and off flavours with
polyphenols and clarity problems with insoluble polyphenol-protein complexes
The use of the “correct” finings agent is generally arrived
at through experimentation. The degree of clarity required depending on
your intended use and its appearance after course filtration. Fining of
red wines is a concern due to suspected removal of flavour components,
in this case gravity may be the best fining agent. Experience may be the
best teacher but trial and error can produce some less than desirable consequences
such as completely stripped wines. It is often more practical to do nothing
rather then fine a wine with an inappropriate material or a matter of practice.
As shown above there are a lot of materials that can be
used and have been used over time to clarify a wine. The Romans experimented
using sea water to help clarity their wine. Listed below we’ll review a
number of the conventional clarifiers with regard to their functionality,
uses and restrictions. Top of Page
Bentonite / Bentogran (proteins)
AKA: Montmorillonite clay. Naturally occurring
aluminosilicate of sodium, calcium, magnesium, and iron.
Kaolin clays are used as fillers in many commercially available products
but have a lower surface area and efficiency of use. The name Bentonite
comes from the place where it was originally mined Fort Benton, Montana.
Methodology: Bentonites negative charge attracts
positively charged particles, such as protein, to its surface and gradually
carries them down due to the forces of gravity. Bentonite absorbs a large
quantity of water, which increases its surface area and aids in deproteinizing.
The alkaline/basic nature of bentonite results in a rapid reaction in the
acidic wine resulting in simultaneous combination with proteins & other
positively charged particles. Bentonite is relatively non-specific, absorbing
Effects: Benign in flavour retention. Best for
protein stability. Doesn’t affect tannin levels. Polyphenols, and colour
loss with red wines while sodium, calcium, ash and alkalinity are increased.
The colour loss in reds is generally the insoluble / unstable colouring
materials. Can inhibit completion of fermentation and has bulky lees (easily
Uses: Fining agent that acts as a protein
remover. Also useful when added to a clear juice must at the beginning
of a fermentation to provide yeast nucleation sites and speed the onset
of fermentation. Use 1/2 g per litre of wine or a 5% slurry. Dissolve
by blending into water (for every gram of bentonite use about 25 ml of
water: (If added during fermentation use 0.8-1.3 g / L, if added after
fermentation use 0.25-0.375 g/L). Allow to stand for 24 hours and stir
thoroughly into wine. The newer KWK Agglomerated Bentonite may be used
after 1-2 hrs hydration time. Wait two weeks and then rack wine from sediment.
5 ml (one teaspoon) = approximately 3g. When used in conjunction with kieselsol
and gelatin there seems to be a difference of opinion as to whether to
add the bentonite prior to the kieselsol or after the gelatin.
Optimum Temperature: 10oC to 25oC. Best performance
in the upper part of the range.
Contra-indications: Using more than the recommended
amount can strip anthocyanins / melanoidins (colour and flavour compounds)
from a wine.
Storage: Cool and dry.
Hazard Classification: Very low. Prolonged breathing
of dust can cause respiratory disease. Top
Gelatin / Enolophin pH
/ Gelsol (proteins & higher polyphenols)
AKA: Liquid gelatin finings or dried form. Gelatine
Extra No.1, Gecoll Supra 95, Gelarom, Gelaffort, Gecoll and Gecoll No.5.
Davis unflavoured gelatine.
Composition: 100% animal-derived gelatin.
Composed of aminoacids primarily glycine, proline and hrydroxproline. Produced
from cooking / controlled partial hydrolysis of fibrous insoluble protein
collagen found in bone, tendons, skin and connective tissue. pH of a 1%
solution ranges from 4.5-6.5. Gelatin is characterized by bloom value which
refers to the size of the gelatin molecule and consists of proteins of
various natures and in variable proportions. In the wine industry low bloom
values of 70-200 are used and when used in conjunction with keiselsol bloom
values of 70-130 are preferred. The choice of gelatin can have an
impact on its effectiveness.
Methodology: Gelatin is colloidal in nature and
primarily has a positive charge. Gelatin requires tannin to flocculate
which limits its to use primarily red wines. It attracts tannins which
are primarily negatively charged. Once this neutralization has occurred
the turbid particles tend to agglomerate which in turn causes them to settle
out. Acts on both proteins and tannins. Gelatin can also be used to preserve
clarity, and improve the sensory qualities, soften the wine and balance
Effects: reduces astringency in red wines by lowering
tannin levels. Tends to remove more higher M.W. tannins than lower M.W.
ones. (The former are perceived as astringent, the latter as bitter). Improves
and removes colour.
Uses: Positively charged fining agent for
wine and beer. Can be used alone or in conjunction with Enolophin 700 /
Neosol. The most powerful of the organic finings, gelatin will also remove
excess tannins (polyphenolics) and colouring particles (melanoidins) from
wine. For Enolophin 700 use .66 ml per litre (about 15 ml per 23 litres).
non-flavoured gelatin powder use 1 g / 20ml solution and 18ml of solution
per 19 L carboy. Use a syringe for accurate measurement. Place gelatin
container in hot water to soften contents. Stir into wine or beer thoroughly.
Wait two weeks and rack from sediment.
Preparation: dissolve the gelatin in warm/hot not
boiling water. Always add the gelatin to the water not water to the
gelatin. Don’t dissolve gelatin in the presence of acids or juices. Use
is typicallly in the range of 0.1-0.2 g gelatin / L wine (less for
white more for reds). Make up a dilute solution as above and add the desired
amount with a syringe.
Optimum Temperature: 10 to 25oC. Works best
at the lower end of the range.
Contra-indications: Using more than the recommended
amount will remove too much of the colour and flavour compounds from wine
and some of the body from beer. In older wines where the tannins have had
a chance to
polymerize gelatin can strip these astringent tannins
leaving fewer to mask the bitter tannins. Gelatin provides proteins that
fix onto the tannin, however , if used in excess means that a major quantity
of protein will be in the wine leaving a haze (i.e. in white wines that
are low in tannin).
Storage: Keep refrigerated. Top
Enolophin 700 / Neosol(proteins)
AKA: Kieselsol. Baykisol. Sihasol. Silicon
dioxide. Silica. Silica Sol. The other part of Enolophin 2 part finings.
Composition: Solution of about 30% silicon
dioxide in water suspension. Colloidal solutions of high molecular weight,
high surface area polymers of silicic acid. PH 9.8-9.9. Negatively charged.
Methodology: Strong protein reactants. Characterized
by increased floc sizes which result in more rapid sedimentation. These
should be used in conjunction with gelatin but added prior to the gelatin.
More specific for higher molecular weight proteins.
Uses: Fining agent for beer or wine. Should be
used in conjunction with gelatin. For Enolophin 700 use 2.2 ml per Litre
of wine or beer (about 50 ml per 23 litre batch). For Neosol the suppliers
suggested use level are; must (0.5-1 ml/L), wine (0.3-1 ml/L). Ludvik’s
suggestion is 0.44
ml/ Litre of wine (8.4 mls per 19L carboy). Use
a syringe for accurate measurement. Stir thoroughly. Wait two weeks and
rack off sediment.
Storage: Unlimited when kept in the orignal
container at above 6C. Do not freeze or refrigerate. Seal tightly when
not in use. Top of Page
Egg Whites (higher polyphenols)
AKA: Egg white, dried powder, frozen egg whites,
Composition: Proteinaceous; contains albumen
and globulin (dried is 84-87% protein)
Methodology: Albumen is colloidal in nature with
a positive charge on its surface. It attracts tannins (negatively charged).
Once this neutralization occurs the turbid particles agglomerate and settle
out due to gravity.
Uses: Positively charged fining for wine.
Works similar to gelatin, removing tannins and some colour. Separate
the egg white completely from the yolks. Dosage is 1/5 to 1/2 egg white
per 23 litres. Gently beat white with 500 ml of wine and a pinch of
salt (aids in solution of the globulin), remove any foam/froth from the
surface, then stir immediately into the wine. (Do not beat stiff, just
loosen up the white so it will mix into the wine). Wait two weeks and rack.
This is the only fining agent used on the great red wines of Burgundy.
If using dried albumen use 8 to 15 grams per hectolitre. (Note: 1 Kg of
dried albumen ~ = 280 eggs)
Advantages: Changes the tannin structure in reds
favourably, making them more supple, but not thin.
Optimum Temperature: 10 to 25oC. Works best in
the lower part of the range.
Contra-indications: Tannins are attracted to the
albumen because their surface electrical charge has been removed. The wine
becomes temporarily cloudy while the flocculates agglomerate then settle.
There is loss of colour. Not suitable for white wines. Top
AKA: Glue. Fish glue. Made up of collagen fibres
derived from the air bladders of certain fish.
Composition: Shredded, freeze dried, powdered
swim bladder of sturgeon dissolved in liquid suspension.
Methodology: Like gelatin this is positively charged
but unlike gelatin it does not require the presence of tannins to act on
the wine, making it a preferred clarifier for white wines. A less efficient
/ more gentle fining agent than gelatin.
Uses: Positively charged fining agent. Traditionally
used for beer but can also be used for wine. Extremely gentle. Use 1
ml per litre of beer or wine. Dissolve into 250 ml of water and stir
thoroughly into beer or wine. Wait two weeks and rack off sediment.
Contra-indications: Not as strong as any
other fining; may fail to clear completely. Avoid over fining.
Advanatges: The addition of proteins resulting
from the use of Isinglas lends a brillance to the colour and mouth feel.
Storage: Tightly sealed. Top
Polyclar (low M.W. polyphenols)
AKA: Polyvinylpolypyrrolidone food grade.
Polyclar AT /10. Polyamide
Composition: a high molecular weight crosslinked
polyvinylpyrrolidone supplied as a white powder (similar to nylon but with
a more compact structure – more hydrogen bonding)
Methodology: appears to be through the formation
of hydrogen bonds between the carbonyl groups of the Polyclar and the phenolic
hydrogens of the polyphenols. Remarkable ability to complex with a wide
variety of materials. It attracts the low molecular weight polyphenols
rather than the condensed tannins and leucanthocyanins that are removed
Polyphenols can be divided into catechins, flavanols and
anthocyanogens, plus phenolic compounds and polymeric polyphenols or tannins.
Uses: Stabilising additive for wine or beer. Removes
polyphenolic compounds and oxidised melanoidins. This means that when used
in beer it will remove haze-causing husk tannins and oxidized compounds
that contribute to off flavours. When used in a finished wine it can help
remove haze-causing proteins. More importantly, it can
remove oxidized flavour and aroma compounds, making the wine taste fresher
while improving and enhancing the aroma. Also able to gently reduce tannins.
Use 1/2 g per litre of wine or beer. Typical range
is 0.25-0.75g/L. May be directly added or dissolve powder in
500 ml of the wine or beer. Stir into larger amount, mixing very well.
Wait for one week and rack from sediment. May cause gushing and foaming
when added; when in doubt, add to wine or beer in a container with 25%
larger volume than the liquid
inside. 5 ml (one teaspoon) = approximately 1.1 g. Note:
contact time is important. A minimum of 24 hrs is required, longer exposure
should have no harmful effects.
Optimum Temperature: 10-25oC preferrably at the
lower end of the range.
Advantages: the reduction in polyphenols does not
adversey affect the flavour. Easily reoved by filtration. Can stabilize
the colour in white and rose wines. Removes the polyphenols and protein-tannin
complexes. Lowers bitterness in wines.
Contra-indications: Although Polyclar will remove
haze it is not primarily a fining agent. Using more than the recommended
amount can strip melanoidins (colour and flavour compounds) from a wine.
Polyclar is highly selective, it can adsorb up to 4 times as much polyphenols
as nylon. Wine should be filtered after use.
Storage: Room temperature.
Hazard Classification: Low. Inhaled dust irritant
Top of Page
/ metal ions)
AKA: Celite. Calcined diatomaceous earth. Kieselguhr.
Composition: Crystalline Silica, quartz aluminasilicate,
cristobalite. It contains colloidal compounds which make it gel, and the
silica is derived from the preserved skeletons of marine animals
found in dry seabeds. Complex of various polysaccharides and diatomaceous
earth. The diatom is a microscopic organism in colonial algae that has
a silicified skeleton.
Methodology: attracts negatively charged
particles and removes the surface charges which allow agglomeration of
the colloidal particles then settling due to gravity.
Effects: Clarifies a broad pectrum of hazes.
Good at removing hazes left from using other fining agents and in removing
cations such as copper. Little effect on flavour or colour. Most wines
are easier to filter. Noted for working when other fining agents have failed.
Also provides a compact sediment bed, pressing down other fining agents
and increasing yield. Used as a coating medium for filter pads, to decrease
Uses: Positively charged fining agent for
beer and wine. To use, stir 25 g of Sparkolloid into 1 litre of briskly
boiling water. (Use 40ml of water per gram of Sparkalloid.) Boil for three
minutes, stirring well to completely dissolve. All of the translucent globules
must be dissolved and the mixture should be smooth and creamy. Use 12.5
ml of the prepared solution for every litre of wine (about 300 ml for 23
litres). This equates to a dry solids basis of 0.13 to 0.4 grams /
Litre. Stir thoroughly into wine, leave for 2 weeks, then rack off sediment.
Store remaining solution in tightly sealed bottle. Will keep for 6 months
or more. 5 ml (one teaspoon) = approximately 1.2 g. The solution is best
added to the wine while hot.
Optimum Temperature: 10-25oC. Does better
in the lower end of the range.
Contra-indications: Preparation for use is
not straight forward. Should be filtered after use. In the U.S. the wine
must be filtered to be sold as commercial wines after use of Sparkalloid.
Cold mix Sparkalloid is not as effect as the hot mixed version. Do not
use in conjunction with gelatin.
Storage: Keep dry, Seal tightly when not in use.
Hazard Classification: Low. Prolonged exposure
to dust can cause lung irritation. Top
Activated carbon (polyphenols)
AKA: Norit. Carbogran.
Composition: pure form of carbon
Effects: an excellent adsorbant of benzenoid
compounds. Acts to remove / partially remove all classes of polyphenols
and is fairly non-specific. Used to decolorize and deodorize juices and
Uses: add the carbon as a slurry to a portion of
the juice or wine to be treated. The most optimum time to add the carbon
is a soon as possible after fermentation but before bentonite addition.
Carbon added by itself is difficult to remove by filtration and should
be followed by additional fining such as bentonite or sparkaloid to assist
in settling of the carbon. Carbon should be removed from the wine as soon
Advantages: can be used to assist precipitation
during fermentation, clarify wine, remove excess colour in white wine,
remove excess colour in dry sherry’s, reduce colour in red wines such as
for blush wines, reduce the varietal character in late harvest wines
Contra-indications: overuse can strip flavour,
colour and aroma. Generally used as a last resort. Top
Casein is sodium or potassium
caseinate which is the primary protein in milk. Both are obtained through
the precipitating action of acid on milk. The caseinates exert a binding
action on the haze particles and reduce unwanted polyphenol contents such
as tannins. The acidity of the wine causes the alkali casein to lose its
counterion, making it less soluble, resulting in turbidity and the gumming
action of haze removal.
In addition the proteinaceous nature of casein allows
it to from complexes with tannin. It is can be used to remove metal salts
from the wine. Egg albumen works similar to casein in being able to remove
astringency in reds through higher tannin removal. Skim milk powder is
a source of the caseinates. When used in conjunction with PVP can adsorb
stale flavours and reduce discoloring due to ageing. Casein has to be specially
prepared in a high pH solution and added very quickly to the wine because
it precipitates almost instantly. Most of the effects are better handled
with Polyclar or gelatin. Top of Page
New Combinations: colloidal silica and chitosan
This combination is reported to replace isinglas for white
wines and gelatin or red wines. The colloidal silica binds to the smaller
proteins and pulls them together (agglomerates them). Chitosan being derived
from the shells of shellfish and crustaceans acts as an all encompassing
flocculating agent that removes all solids, including the larger proteins
brought together by the colloidal silica.
There are other fining agents that have traditionally
been used, including blood, agar-agar, and occasionally milk. Blood is
tough to get and to keep fresh. Agar-agar is a good fining agent, but can
be very expensive. Gelatin works just as well and is cheap. Milk is mentioned
in some wine-making books under the heading of casein, which is the protein
compound responsible for the fining action.