Page 16 - Grapevine NovDec 2020

In The Winery

Equipment Needed for Fining Trials the same age, for a good comparison tasting. This
would be an excellent way to do a cellar trial in the
Most winery labs have the basics and one should winery with very controlled results if you find fining
be able to acquire additional items needed with lit- trials difficult in the lab. Dilution schemes of egg
tle financial outlay. Here is a list of basics. whites in the lab are difficult but do the best you
can.
1. 375 milliliter screw cap wine bottles (splits) –
may reuse these. Gelatin: Gelatin is a great fining agent typically
2. Accurate scales used early on in the juice or wine. It is known for
3. 500 ml beakers being aggressive and potentially “stripping” the
4. 500 ml Erlenmeyer flasks wine is more likely with gelatin. That said suppliers
5. Stir plate with magnetic stir bars have rapidly introduced what I call “target specific
6. Distilled water or winery tap water used for gelatins” that can enhance or mute certain aromas,
mixing fining agents. and modify specific areas of the palate. These are
7. Graduated cylinders: 50 mil, 100 mil, 250 mil much more refined products than say 20 years ago
8. Pipettes: 1 and 10 milliliter serological pipettes when “bloom and mesh” was the only real differen-
9. Wine glasses – never forget the wine glass! tiation between different grades of Gelatin. Gelatin
is made from collagen in animals and typically binds
Some Common Fining Agents with larger molecular weight [tannins / catechins
and Their Projected Uses etc] and removing more phenolic compounds from
the wine. So if a wine is heavy in tannins and phe-
Casein: This is the principal protein found in milk nolics a review of a gelatin fining trial may be in
and milk is approved by the TTB ( Tax and Trade order. Gelatin does absorb and remove color so
Bureau) to be added to wine. Casein is positive- use with caution. As always – do trials in the lab
ly charged and is used mostly as a fining agent in first. Because different products have different rec-
whites wines that have been in the cellar for an ommended rates I am steering clear of making any
extended time – perhaps over two years. The blanket recommended ranges to try and will refer
action of casein tends to clean up some color you to the supplier of the specific product you care
issues as well as remove some of the aged qualities to experiment with.
including off contributing color compounds. Each
wine reacts differently to casein so trials must be Isinglass: An amazing agent because it is fish col-
performed in the lab, on a small scale, to under- lagen or sturgeon bladders ( buoyancy bladder ) I
stand how your particular wine will react. Either am told. Who in the world thought of adding this
follow the suppliers recommended rates or if using to wine? This is a gentle protein fining agent used
milk you may use up to 7.5 liters of whole or skim mainly on white wines to help elevate / improve
milk per 1000 gallons since that is the TTB limit. the aromatics and improve clarity with improved
lees compaction if used with bentonite. Most likely
Egg Whites: (Albumin): A very proven effective used 30-60 days prior to bottling and while “finish-
and soft approach used for a very gentle fining ing the wine out”. A very gentle fining agent and
mostly on red wines in barrel. Only the whites of worth trying in the ranges of 1/16 – 1/3 pound per
the egg are used, mixed with a “pinch” of potassi- 1000 gallons. A very nice, soft fining agent and
um chloride salt and a small amount of water. Stir even try it with red wines – you may be surprised
the egg white mix gently into the barrel and allow at the results in your trial and decide to use it on
the wine to settle for 30-45 days. For larger win- your reds. Some colleagues in the Napa Valley
eries that want to do a trial in the cellar one could have seen great results with Isinglass on their reds.
use: One egg white in one barrel, two egg whites
in another, three in another and so on up to a typi- PVP: (Polyvinylpolypyrolidone) This is a synthetic
cal maximum of 6 egg whites per barrel. Make sure material that binds mostly to athocyanins (color)
to do this on the same wine in barrels, of nearly and catechins (smaller phenolic compounds). Often

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