Winemaking in the Classroom 3 Clarification, Finishing and Bottling Sirromet Wines Pty Ltd 850-938 Mount Cotton Rd Mount Cotton Queensland, Australia 4165.

Winemaking in the Classroom 3

Clarification, Finishing and BottlingClarification, Finishing and Bottling

Sirromet Wines Pty Ltd850-938 Mount Cotton Rd

Mount Cotton Queensland, Australia 4165www.sirromet.com

Courtesy of Jessica Ferguson

Assistant Winemaker & Site ChemistDownloaded from seniorchem.com/eei.html

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Clean-up, add preservative

When wine is dry, or by desired sweet style When wine is dry, or by desired sweet style cool vessel down – colder the better, to help stop cool vessel down – colder the better, to help stop

yeast and encourage settling of dead yeastyeast and encourage settling of dead yeast add SOadd SO22 when cool – Camden tablets or Potassium when cool – Camden tablets or Potassium

Metabisulphite (PMS) saltMetabisulphite (PMS) salt aim for >35mg/L Free SOaim for >35mg/L Free SO22

Consider that PMS is only 57% SOConsider that PMS is only 57% SO22

At least 50% of added SOAt least 50% of added SO22 will convert to bound will convert to bound SOSO2 2 directly following fermentationdirectly following fermentation

Clarification - Racking

Initially, allow wine to settleInitially, allow wine to settle Ensure that containers are fullEnsure that containers are full Transfer carefully (no splashing) to smaller Transfer carefully (no splashing) to smaller

containers, or top up containers and seal.containers, or top up containers and seal. Avoid oxygen/air exposureAvoid oxygen/air exposure May need successive rackings to achieve May need successive rackings to achieve

clarification – more settling occurs following clarification – more settling occurs following each rackingeach racking

Racking

Separation of clear wine from settled Separation of clear wine from settled solids (lees)solids (lees)

Best to use a siphon with the end of Best to use a siphon with the end of the hose held above the leesthe hose held above the lees

Rack wine into a smaller container so Rack wine into a smaller container so that vessel is fullthat vessel is full

Always keep wine vessels fullAlways keep wine vessels full unless unless fermentingfermenting

This prevents spoilage due to This prevents spoilage due to oxidation or aerobic microbesoxidation or aerobic microbes

Further clarification aids Bentonite – clay mineral used for clarificationBentonite – clay mineral used for clarification Try 0.25gm/L dose in wine Try 0.25gm/L dose in wine Make up as 5% slurry in waterMake up as 5% slurry in water Make up day before use to allow swelling of particlesMake up day before use to allow swelling of particles mix vigorously (use electric beater) while adding powder mix vigorously (use electric beater) while adding powder

slowly to hot waterslowly to hot water Add to wine immediately after SOAdd to wine immediately after SO22 addition, or after racking addition, or after racking

for further clarificationfor further clarification Rack clear wine 2 days after bentonite additionRack clear wine 2 days after bentonite addition Wine should not be chilled – bentonite works better over 10Wine should not be chilled – bentonite works better over 10˚C˚C

Safe wine storage

Full containersFull containers low dissolved oxygenlow dissolved oxygen Free SO2 >35mg/l @ Free SO2 >35mg/l @

pH 3.20pH 3.20 no fermentable sugars no fermentable sugars

leftleft Keep wine cool – Keep wine cool –

1515˚C is great, but at ˚C is great, but at least <20˚C. least <20˚C.

Finishing wine – fining and stability Consider acid addition trial for flavour and balance Consider acid addition trial for flavour and balance

(can use citric or tartaric acid)(can use citric or tartaric acid) Other fining agents: powdered milk, gelatine, isinglass Other fining agents: powdered milk, gelatine, isinglass

- to alter or reduce bitterness, phenolics, tannins- to alter or reduce bitterness, phenolics, tannins Good idea to trial all finings on bench firstGood idea to trial all finings on bench first 100mL wine samples, add solution of fining agent 100mL wine samples, add solution of fining agent

equivalent to final dose in wineequivalent to final dose in wine For example, to trial a 0.2g/L tartaric acid addition:For example, to trial a 0.2g/L tartaric acid addition: add 0.2mL of a 10% tartaric acid solution to 100mL of add 0.2mL of a 10% tartaric acid solution to 100mL of

wine on the benchwine on the bench

Finishing Wine - Stabilising Protein stability: More an issue for white-style wines, Protein stability: More an issue for white-style wines,

prevents protein haze in bottled wineprevents protein haze in bottled wine Proteins are removed by bentonite finingProteins are removed by bentonite fining Test for protein stability: heat a filtered wine sample Test for protein stability: heat a filtered wine sample

for 6 hours at 80for 6 hours at 80˚C, cool and check for haze ˚C, cool and check for haze formationformation

Cold stability: Prevents tartrate precipitation in bottle, Cold stability: Prevents tartrate precipitation in bottle, difficult to achieve on small volume wines and difficult to achieve on small volume wines and without a way of cold filtering without air exposure without a way of cold filtering without air exposure

Could try refrigerating wine and racking wine off of Could try refrigerating wine and racking wine off of any crystals that precipitateany crystals that precipitate

Finishing Wine - Filtration May not be necessary for some red wines that May not be necessary for some red wines that

have achieved good clarity through have achieved good clarity through racking/fining aloneracking/fining alone

Filtration options – depends on sweetness levels, Filtration options – depends on sweetness levels, persistent turbidity or clarity issues persistent turbidity or clarity issues

Gravity or small electric pad filters are available Gravity or small electric pad filters are available Suggest pad filter just prior to bottling – gives Suggest pad filter just prior to bottling – gives

brilliance to winebrilliance to wine Wine should not be chilled when filtering as this Wine should not be chilled when filtering as this

exacerbates dissolved oxygen pick-upexacerbates dissolved oxygen pick-up

Bottling Logistics In industry we would check the following In industry we would check the following

pre-bottling:pre-bottling:

pH, titratable acidity, free/total SOpH, titratable acidity, free/total SO22, CO, CO22, , HH22S,S,

alcohol, flavour, colour, dissolved alcohol, flavour, colour, dissolved oxygen, protein stability, tartrate (cold) oxygen, protein stability, tartrate (cold) stability, residual sugar, turbidity/clarity, stability, residual sugar, turbidity/clarity, specific gravityspecific gravity

Adjust Free SOAdjust Free SO22 levels to 35-40mg/L levels to 35-40mg/L Use clean, preferably sterilised bottlesUse clean, preferably sterilised bottles Fill bottles carefully with no splashing (avoid Fill bottles carefully with no splashing (avoid

increasing dissolved oxygen)increasing dissolved oxygen) Seal with screw-caps, crown seals or corksSeal with screw-caps, crown seals or corks

Finally….. A word of caution

If wine is not dry at bottling, be aware of If wine is not dry at bottling, be aware of the risk of re-fermentationthe risk of re-fermentation

Increase SOIncrease SO22 levels pre-bottling to FSO levels pre-bottling to FSO22

> 40mg/L> 40mg/L Can also use Potassium Sorbate at 100-Can also use Potassium Sorbate at 100-

150mg/L as an extra preservative (ensure 150mg/L as an extra preservative (ensure SOSO2 2 levels are adequate for sorbate to be levels are adequate for sorbate to be

effective)effective) Advise that wine should be drunk earlier Advise that wine should be drunk earlier

rather than later!rather than later!