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    EB0719EB0719EB0719EB0719EB0719

    HomeHomeHomeHomeHomeWinemakingWinemakingWinemakingWinemakingWinemaking

    College of Agricultural, Human, and Natural Resource Sciences Washington State University Pullman, Washington

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    General Winemaking ProcedureGeneral Winemaking ProcedureGeneral Winemaking ProcedureGeneral Winemaking ProcedureGeneral Winemaking Procedure

    WhiteWhiteWhiteWhiteWhite

    AddAddAddAddAddSOSOSOSOSO

    22222

    (100 ppm)(100 ppm)(100 ppm)(100 ppm)(100 ppm)

    PressPressPressPressPress

    SettleSettleSettleSettleSettle

    FermentFermentFermentFermentFerment(less than 60F/15.5C)(less than 60F/15.5C)(less than 60F/15.5C)(less than 60F/15.5C)(less than 60F/15.5C)

    FinishFinishFinishFinishFinish

    Age (more applicable to reds)Age (more applicable to reds)Age (more applicable to reds)Age (more applicable to reds)Age (more applicable to reds)

    BottleBottleBottleBottleBottle

    RedRedRedRedRed

    AddAddAddAddAddSOSOSOSOSO

    22222

    (75 ppm)(75 ppm)(75 ppm)(75 ppm)(75 ppm)

    Ferment (35 days)Ferment (35 days)Ferment (35 days)Ferment (35 days)Ferment (35 days)(approx. 80F/26.7C)(approx. 80F/26.7C)(approx. 80F/26.7C)(approx. 80F/26.7C)(approx. 80F/26.7C)

    PressPressPressPressPress

    CompleteCompleteCompleteCompleteComplete

    FermentationFermentationFermentationFermentationFermentation

    Select FruitSelect FruitSelect FruitSelect FruitSelect Fruit

    CrushCrushCrushCrushCrush

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    Despite the claims of some that goodwine can be made only by experts, the ama-teur can produce high quality wines athome. In fact, thousands of people have

    found that satisfactory wine can be preparedat home with easily obtainable materials.

    Wine in the simplest terms is the prod-uct of the fermentation of fruit juice byyeast. During fermentation, yeast convertssugar into roughly equal amounts of alco-hol (ethanol) and carbon dioxide (CO

    2)

    along with numerous minor by-products.This bulletin tells you about some commonproblems in home winemaking, what ma-terials youll need to get started, and howto go about making red, white, and fruitand berry wines.

    Common ProblemsCommon ProblemsCommon ProblemsCommon ProblemsCommon Problems

    SanitationSanitationSanitationSanitationSanitationA very important factor, often overlooked

    by home winemakers, is good sanitation. Thepoint of good sanitation is to ensure that aclean fermentation occurs without contami-nation of the juice with wild yeast or othermicroorganisms that can spoil the wine bycausing off-odors or flavors.

    Consistent winemaking success dependson making sure all of the equipment com-ing into contact with the juice and/or wineis properly sanitized. Clean the equipmentwith a warm, nonodorous detergent solu-tion, then scrub, if necessary, and finally,rinse several times, preferably with hot wa-ter. A rinse with a dilute bleach (hypochlo-rite) or sulfur dioxide (SO

    2) can also be used

    as a final sanitizing step. (Keep in mind that

    hypochlorite tends to corrode stainlesssteel. Fresh, clean water should be used asa rinse.) See Sulfur Dioxide section for moreinformation about SO

    2, page 4.

    Sanitize bottles with a final rinse with a200 parts per million (ppm) SO

    2solution.

    Drain the bottles thoroughly. Sanitize corksby soaking them in a 200 ppm SO2

    solu-tion or by boiling them in water. Afterward,handle the corks only with sanitized tongs.

    Avoid touching sanitized equipment sur-faces or the juice, since the hands are anabundant source of microorganisms, particu-larly of lactic acid bacteria which can spoilthe wine. Dont use your mouth to start thesiphoning action during the final stages ofwinemaking. Instead, use a sanitary suctionbulb or an uncontaminated hose.

    Also be on the alert for Drosophyla

    melanogaster, the fruit fly, a commonsource of wine infection. This source of con-tamination can be controlled to a greatdegree by simple good housekeeping. Dur-ing fermentation of red wines, cover thevessels with a clean sheet or other cloth tokeep the flies away. Clean up all spills im-mediately. Finally, and perhaps most im-portantly, remove pomace, skins, seeds, etc.from the winemaking area immediately af-ter pressing.

    OxidationOxidationOxidationOxidationOxidation

    A second pitfall often encountered bythe home winemaker is oxidation. After theprimary fermentation, in which largeamounts of protective carbon dioxide gas(CO

    2) are produced, you must take precau-

    tions to minimize exposure of wine to air.In the finishing vessel, this is done by fill-ing the containers as full as possible andusing air traps.

    There are several types of air traps. Mostdepend on water as the air lock. The trapallows carbon dioxide to escape while pre-venting air from entering the vessel. You caneasily make a water-type air trap from glassor plastic, or purchase one from a wine shop.

    A second type of air trap, which does notuse water, can be made by using thick-walled surgical tubing. First slit the tubinglongitudinally for 1/2 to 1 inch with a razor.Then plug the tubing at one end with ashort length of glass rod or other clean

    dowel or plug. Attach the other end to aglass tube inserted into a rubber stopper oa size to fit the container being used (Fig1). If the rubber tubing is thick enough andslit properly, it will allow expulsion of gasefrom the container, but will not allow air to

    enter.During the finishing of the wine-racking(siphoning), addition of fining agents, etc.take care to minimize aeration. For examplewhen racking, the siphon hose in the receiving vessel should be below the surface ofthe wine (Figures 2 and 3). However, whenhydrogen sulfide (H

    2S, rotten egg smell)

    is detected, deliberately aerate the vessel toremove the odor.

    IngredientsIngredientsIngredientsIngredientsIngredients

    FruitFruitFruitFruitFruitThe main determinant of the quality o

    any wine is the fruit used in its productionAlways use high quality, sound fruit. This inot to say that overripe fruit cannot be usedHowever, avoid fruit that shows excessivebrowning or contains obvious rot or moldCut out diseased portions of the fruit priorto crushing and extracting the juice.

    3

    HHHHHomeomeomeomeomeWinWinWinWinWinemakinemakinemakinemakinemakinggggg

    by Charles NagelandJoseph Powers,Department of Food Science Human

    Nutrition, Professor Emeritusand Associate Professor,

    Washington State University

    Fig. 1. One style of air trap. The slit allowsgases to escape while preventing air fromentering.

    Glasstube

    Plug

    Rubbertubing

    Slit

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    Often, fruit used for winemaking doesnot contain enough sugar to produce thedesired 10% to 12% alcohol. Table 1 showsthe amount of sugar addition and the re-sulting volume required to adjust the sugarcontent to 23 Balling1, which should en-

    sure at least 12% alcohol if the mixture isfermented to dryness. If a lower alcoholcontent is desired, adjust the fermentationprocess roughly on the basis of a 2-to-1 ra-tio of sugar-to-alcohol yield.

    Among the most common problemswith home wines is the juice has not beenproperly adjusted for acid content. Forlight wines, the acid content should rangebetween 0.65% and 0.8% (expressed as tar-taric acid, weight/volume basis). In sweetwines, acid contents of 1.2% or more areacceptable. In highly pigmented wines,

    which usually contain a large amount oftannin compounds, the acidity can be con-siderably less, since the tannins seem tocompensate for the lack of acidity. There-fore, in heavy red wines, an acidity of 0.5% to 0.7% is generally acceptable. Again,higher acidities are tolerated in sweeter

    wines. In fact, sugar will aid considerably inmaking a harsh acid wine taste less harshand more rounded.

    Table 2 shows the average sugar and acidcontents of a number of fruits used inwinemaking in the Pacific Northwest. Ex-

    cluded from the table are grapes. Generally,if the grapes are produced in central Wash-ington, little adjustment will be necessary.If the grapes are grown in western Wash-ington, however, they usually do not reachfull maturity and often require sugar addi-tion as well as acid reduction.

    The values in Table 2 are average valuesand can vary considerably depending uponthe variety of fruit used. For example, Bingcherries are generally low in acid and mayrequire acid addition, while Royal Ann cher-ries are relatively high in acid and often re-

    quire both sugar addition and acid reduc-tion. Apple varieties are similar. Red Deli-cious are quite low in acid and may requireacid addition, whereas MacIntosh or Wine-sap tend to have enough acidity.

    Other fruits not listed in the table arepeaches, apricots, and pears. Peaches andpears tend to have sugar and acid contentssimilar to apples. When overripe, however,these fruits often require acid addition.

    YeastYeastYeastYeastYeastWhile wild yeasts are found on most

    fruit, and they may be used in a naturalfermentation, they are not a reliable source.A more controlled, predictable fermentationis usually attained with purchased wineyeast. You can buy wine yeasts of severaltypes from wine supply houses, usually in adry granular form.

    Certain wine yeasts are propagated aspure strains and are often named after theregion from which they were originally iso-lated. However, do not presume that by us-ing a certain wine yeast strain (such asMontrachet), a wine will result characteris-tic of the region name. Wines for which aregion may be famous are a result of manyfactorsonly one of which may be the yeast.

    Sulfur DioxideSulfur DioxideSulfur DioxideSulfur DioxideSulfur DioxideSulfur dioxide is discussed here sepa-

    rately since it is most important in thepreparation and preservation of wines. SO

    2

    is used in wines because it prevents oxida-tion. It is also a selective antiseptic that pre-vents the growth of undesirable microor-ganisms, including wild yeast, while allow-ing wine yeast to grow.

    If you obtain Campden tablets from awine supply shop as a sulfur dioxide source,instructions are usually supplied to indicatethe amount necessary to obtain a certainconcentration of SO

    2. If you buy sodium

    bisulfite (NaHSO3), sodium metabisulfite

    (Na2S

    2O

    5), or potassium metabisulfite

    (K2S

    2O

    5), a simple calculation is necessary to

    determine the amount necessary to gener-ate a given amount of SO

    2. These sulfite salts

    are 61.5%, 67.4%, and 57.6% SO2, respectively.

    For example, a 100 ppm (0.01%) SO2

    so-lution from K

    2S

    2O

    5is equivalent to 0.1 gram

    SO2

    per liter. Hence, 0.1 gram divided by0.576 equals 0.1736 gram K

    2S

    2O

    5to make 1

    liter of a 100 ppm SO2

    solution. In gallons(1 gallon = 3.78 liters) 3.78 multiplied by0.1736 equals 0.66 gram per gallon. For ad-dition of small amounts of SO

    2, it is conve-

    nient to prepare a concentrated solutionwhich can then be transferred through a pi-pette (a narrow glass tube) according to thevolume and amount of SO

    2desired. For ex-

    ample, you can prepare a solution contain-ing 100,000 ppm (10%) SO

    2by weighing out

    Fig. 2. During racking, clear wine is siphonedto another finishing vessel placed below the

    first. Sediment is left behind in the uppercontainer.

    1Balling is a term used interchangeably with Brix(pronounced Briks). Both measure the approxi-mate percentage of sugar in the fruit.

    Fig. 3. Take care not to siphon settled sedi-ment during the racking process. Tippingthe upper container can help siphon theclear wine without disturbing the sediment.

    Residue

    Siphoning tube

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    17.1 grams sodium bisulfite, 14.8 grams ofsodium metabisulfite, or 17.4 grams of po-tassium metabisulfite and dissolve withenough water to make up a 100 millilitersolution. Thus, in order to obtain a 100 ppmconcentration, either add 1 milliliter of the

    concentrate to 1 liter of juice or wine or3.78 milliliters to a gallon.

    EquipmentEquipmentEquipmentEquipmentEquipment

    Stemmers and CrushersStemmers and CrushersStemmers and CrushersStemmers and CrushersStemmers and CrushersThe sophistication of equipment used in

    winemaking depends largely on the volumeand type of ingredients you wish to use.

    To make high quality white grape wines,remove the stems before fermentation. Thestems contain a large amount of tannicmaterial which can lead to an overly astrin-

    gent wine. With small amounts of grapes,you can remove the stems by hand. Withcertain red wines it may be desirable to leavesome stems in the must (the juice beforefermentation).

    To prepare grapes for fermentation, theberries must be crushed. It is preferred theyonly be crushed enough to break the berryand force out the pulp and seeds. If youmacerate the skins and seeds the wine maybe highly astringent and difficult to press.A roller-type crusher is recommended. Thistool, however, can be relatively expensive.

    For small amounts you can use a woodenplunger and a suitable container. If you wishto prepare a pulp from stone fruits,(peaches, apricots), any machine, such as ablender, can be used after you remove thepits. One of the simplest crushing devicesis the conical sieve arrangement used in thehomemaking of jellies and jams in whichthe material is crushed with a wooden rollerand forced through the sieve.

    PressesPressesPressesPressesPressesThe simplest type of press for home use

    can be improvised using a coarse cloth orgauze sack. Place the crushed fruit inside thesack, then close the sack by tying and sus-pending it overhead. If you let the sack hangfor an hour or two, a considerable amountof juice will drain without applying pres-sure. Apply pressure by twisting the sack toproduce higher yields.

    A more sophisticated piece of pressing

    equipment is the basket or cider press. Thechoice of size depends on the size of the op-eration. Although the initial investment mayseem high, a press is justified if you expectto make wine year after year. The operationis much faster, and a press yields more juice,particularly from such readily pressablefruits as grapes and apples.

    Primary Fermentation VesselsPrimary Fermentation VesselsPrimary Fermentation VesselsPrimary Fermentation VesselsPrimary Fermentation VesselsSince fermentation produces carbon di-

    oxide, you can use open containers duringthis process. This may be desirable in caseswhere the juice has not yet been separatedfrom the solids, as in red wines. Use anyfood-grade, easily cleaned containers suchas crocks or large plastic containers. Plasticcontainers are easily cleaned, virtually un-breakable, and if the proper plastics are se-lected, nontoxic. Loosely place some typeof lid or cover on top to prevent exposure

    of the fermenting material to contamina-

    tion from the environment.

    Finishing VesselsFinishing VesselsFinishing VesselsFinishing VesselsFinishing VesselsOnce the vigorous stages of the fermen-

    tation are completed and the juice has beenseparated from the solids, transfer the juiceto closed containers with some type of airtrap to minimize exposure to air. The ideacontainer is the glass jug. You can usuallyfind gallon jugs or smaller bottles at garagesales, second-hand stores, or even recyclingcenters. Keep several jugs on hand. Moreconvenient are the 5-gallon carboys com-monly used for distilled water readily available in most winemaking shops. Use glasscontainers, not plastic. Glass containers canbe readily inspected for cleanliness. You canalso easily observe the progress of the fer-mentation and clarification of the result-ant wine.

    All finishing vessels must be easy to clean

    Ballingof juice

    0

    12345678910111213141516171819202122

    Dextrose (lb)

    2.8206

    2.70842.59552.48152.35892.25112.13432.01681.89841.77881.65841.53701.41451.28521.13351.04140.91490.78750.65900.52940.39860.26680.1340

    Resulantgallonage

    1.2203

    1.21151.20271.19391.18411.17591.16681.15771.14851.13911.12971.12031.11071.10041.08771.08151.07161.06171.05161.04151.03121.02091.0105

    Cane orbeet sugar (lb)

    2.4877

    2.38872.28902.18862.08041.98531.88231.77871.67431.56881.46261.35561.24751.13351.02910.91840.80690.69450.58120.46690.35160.23530.1182

    Resultantgallonage

    1.1836

    1.17651.16921.16471.15361.14341.13921.13161.12391.11611.10831.10041.09241.03381.07631.06811.50981.05151.04421.03461.02611.01741.0088

    Table 1. Amounts of dextrose or sucrose required per gallon to increase the solublesolids of juice to 23 Balling.

    Source: U.S. Internal Revenue Service (1961), U.S. Laws (1954).

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    incapable of imparting of f-flavors or odors.Select plastic containers carefully, sincesome contain toxic materials.

    Racking MaterialsRacking MaterialsRacking MaterialsRacking MaterialsRacking Materials

    During the finishing of the wine, solidmaterials settle out of the wine. Thus, youmust rack or siphon off the clear winewithout disturbing the solids on the bot-tom (see Figures 2 and 3). Clear plastic hosesof Tygon or similar material are convenient

    for this operation. Attach the hose to a bentglass or plastic tubing placed in the con-tainer and hold it so that it does not dis-turb the solids on the bottom. With a trans-parent hose, you can observe the operation

    more easily and can determine when de-bris is being siphoned.

    Fining MaterialsFining MaterialsFining MaterialsFining MaterialsFining MaterialsAfter a number of rackings, the unfin-

    ished wine may not yet be crystal clear. Thus,

    you may need to fine to remove the remain-ing small suspended particles from the wine.The most common fining agents are bento-nite and Sparkalloid. Bentonite is an alu-minum silicate clay which will strongly bindproteins and form a floc (a light fluffy mass)

    that will asborb colloidal material on itssurface and then settle out of the solution.To use bentonite effectively, moisten it wellbefore use. Heating helps hydrate it. Preparea bentonite solution at least one day in ad-vance. Normally, winemakers prepare a 6%solution (about 2 ounces per quart, or 60grams per liter). Directions for use ofSparkalloid (a proprietary agent) are usu-ally supplied with the material.

    For highly tannic wines, which includehighly pigmented red wines, use a proteinfining agent. The protein combines with

    tannins and forms a floc. This can reducethe astringent character of a wine. The mostcommonly used protein fining agents aregelatin, casein, and egg white.

    With bentonite, casein, or gelatin, thequantity commonly used is 0.08 to 0.64ounce (2.27 to 18.2 grams) per 10 gallons(37.8 liters) of wine. Bentonite is usuallyused with white wines and 0.32 ounce (9.1grams) per 10 gallons of wine is usually suf-ficient to obtain adequate stabilization andclarification. About 0.16 ounce (4.55 grams)of protein fining agent per 10 gallons of red

    wine is usually adequate.

    Laboratory Materials and MethodsLaboratory Materials and MethodsLaboratory Materials and MethodsLaboratory Materials and MethodsLaboratory Materials and MethodsYou should have a hydrometer for mea-

    suring the soluble solids (sugar content)of the juice and fermenting wine (Fig. 4).A hydrometer is a cylindrical glass devicewith a bulb on one end containing a densematerial. The slender end is divided into ascale usually in degrees of Brix or Balling. Thehydrometer is floated bulb down in the juiceor wine, and a reading is taken from the Brixscale at the meniscus (where the liquids sur-face meets the scale). The reading for all prac-tical purposes equals the percentage of sugarin the liquid. The hydrometer must be cleanand dry before use.

    You also need to measure titratable acid-ity (TA). Equipment required includes a 10-milliliter burette (a graduated glass tube),a 1% phenolphthalein solution, a 0.1 N (nor-

    Fruit

    AppleBlackberry

    CherryCurrantLoganberryPlumRaspberry

    Table 2. Average sugar and acid contents of several fruits used in winemaking in thePacific Northwest.

    Source: H. Y. Yang and E. H. Wiegand, Production of Fruit Wines in the Pacific Northwest, FruitProds. J. (1949), pp. 8-12, 27, 29.

    Total sugar (%)

    11.27.2

    8.56.46.9

    12.06.8

    Total acid ( % )

    0.70 as malic1.20 as citric

    1.00 as malic2.10 as citric2.00 as citric0.90 as malic1.60 as citric

    Fig. 4. The hydrometer is an essential tool in home winemaking. It measures the sugarcontent of the juice and fermenting wine. Take readings at eye level at the meniscus, wherethe concave portion of the liquids surface meets the hydrometer scale. For accurate read-ings, make sure the hydrometer comes to rest in free suspension without touching thesides of the container.

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    mal) sodium hydroxide solution, a 100-mil-liliter beaker, a glass rod, and a 5-milliliterpipette. Perform the titration as follows:1. Fill the burette (a 10-milliliter pipette can

    be used instead) with the sodium hydrox-ide solution and allow a small amount to

    run through. Record the sodium hydrox-ide level in the burette.2. Place about 50 milliliters of hot distilled

    water in the beaker.3. Add 5 milliliters of juice to be tested to

    the hot water using the pipette.4. Add 5 drops of the phenolphthalein so-

    lution to the water-juice mixture.5. Slowly add the sodium hydroxide from

    the burette to the mixture, stirring withthe glass rod. Stop the sodium hydroxideaddition when the mixture turns pink.

    6. Record the sodium hydroxide level in the

    burette, and calculate the number of mil-liliters used. Multiply the volume of so-dium hydroxide used by 0.15. The prod-uct is the percentage of titratable acidityof the sample expressed as tartaric acid.Since you must weigh the preparation of

    the proper concentrations of several materi-als (fining agents, sulfur dioxide, etc.), acquirea single or double beam balance capable ofweighing up to 200 grams. (Table 3.)

    Steps in WinemakingSteps in WinemakingSteps in WinemakingSteps in WinemakingSteps in Winemaking

    White WineWhite WineWhite WineWhite WineWhite WineCrush white grapes as soon after harvest

    as possible. While crushing, add enoughsulfur dioxide to produce about 100 ppm(0.01%) in the juice. At this time, add pec-tin enzymes, if they are to be used, to helpclarify the juice and aid in pressing. Allowthe resultant juice, must, to stand for 4to 18 hours on the skins in order to extractcharacter from the skins. Drain the mustand press the solids (pomace) to extract theremaining juice. Put the combined juices inclosed containers, and store at cool tem-peratures overnight to allow the solids tosettle. At this time, take a sample and checkit for TA and soluble solids. Then siphon theclear juice into clean containers that willbe used for the primary fermentation andadjust the sugar and acid levels if necessary.

    You can combine the remaining solidsand repeat the settling procedure to increase

    yield. Eventually, the solids can be fermentedseparately to maximize yield. Carefully watchthe juice resulting from the solids, since it isin this material that you may most often en-counter problems with hydrogen sulfide pro-duction through the action of the yeast. The

    settling operation as a whole is optional. Theprocedure, however, does produce a cleaner,fruitier wine than if the juice is fermentedwith the solids in it.

    The most convenient way to start the fer-mentation is to add dry yeast directly tothe must. The safest, most sure method,however, is to prepare a small amount ofmust ahead of time and add dry yeast, gen-erating an actively fermenting starter whichis added to the bulk of the must. (Do thiswhile settling is underway.)

    Ferment white wines at cool tempera-

    tures (preferably below 60F/15.5C) sincethis best retains desirable aromas. If you dothe active primary fermentation in an opencontainer, transfer the fermenting juice toa container to which an air trap can be at-tached in the latter stages of fermentationwhen CO

    2evolution slows. This will mini-

    mize danger of the fermentation stopping(sticking) and avoid oxidized wine.

    Red WineRed WineRed WineRed WineRed WineThere are two major differences between

    red and white wine production. First, most

    of the color and tannins are contained inthe skins, particularly in red grapes. Thus,in order to extract these components youmust carry out the fermentation in thepresence of the skins. Second, since we usu-ally wish to emphasize factors other than afresh, fruity character in red wines, fermen-tation is done at relatively high tempera-tures (80F to 85F/26.7C to 29.4C).

    You may remove stems either before orafter crushing. Add about 75 ppm (0.0075%)sulfur dioxide. After crushing, allow the mustto stand overnight so the SO

    2can work.

    (During this period, measure and adjust thesoluble solids and acidity of the must.) Addan actively fermenting yeast starter. Do notfill the containers more than about 2/3 fullin order to avoid overflowing.

    After fermentation starts, the skins willrise to the top of the container. Punch themdown at least twice daily to aid in color and

    tannin extraction. If you look at the juiceand skins, you can normally determinewhen color extraction is nearly complete

    (normally 3 to 5 days of active fermenta-tion). The extent of color extraction you al-low depends on the type of final productdesired. If a ros wine is the objective, re-move the skins sooner than if you want arobust, deeply colored, highly tannic prod-uct, which normally requires more aging. Foa ros, use a lower fermentation tempera-ture, since that will emphasize the fruitycharacter of the grape.

    After color has been extracted, remove theskins and solids, and press to extract thejuice. You can skim most of the skins off the

    top of the actively fermenting juice. Screenthe rest of the juice or run it through acoarse cloth to remove the larger solid materials. Combine the press and screen juicesand put them in closed containers with airtraps to prevent entrance of oxygen.

    Malolactic FermentationMalolactic FermentationMalolactic FermentationMalolactic FermentationMalolactic FermentationNormally, red wines are allowed to un-

    dergo malolactic fermentation (the conversion of malic acid to lactic acid and carbondioxide by lactic acid bacteria). This fermen-tation results in a reduction in the total acid-ity of the wine because lactic acid has oneacid group while malic acid has two. Thisprocess is needed because the tannins in redwines accentuate the acid character resulting in harsh tasting wines.

    Dry preparations of Leuconostoc oenosare available with directions for rehydrationThe culture should be added to the ferment

    Table 3. Metric equivalents of commonmeasures.

    Approximate weight(gram/tsp)

    5.6

    3.15

    6.7

    1.3

    Material

    Bentonite(granular)Gelatin

    (food grade)Potassium

    metabisulfite( crystal )

    Sparkalloid

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    ing must after extraction of the solids. Af-ter adding the culture the wine should bestored in closed containers with an air trapat room temperatures (68F, 20C) until themalolactic fermentation is complete (usu-ally 2 weeks to 2 months; carbon dioxide

    evolution should stop and titratable acid-ity reduced).

    Fruit and Berry WinesFruit and Berry WinesFruit and Berry WinesFruit and Berry WinesFruit and Berry WinesYou can make other fruit and berry wines

    by procedures similar to those for grapewines. One of the major differences is thatyou will have to macerate the fruit into thickpulp that is not easily pressed. In this case,it is wise to ferment the whole pulp, and,as the pulp rises to the surface during ac-tive fermentation, scoop it off and drain itthrough a fine-meshed cloth. If you do this

    during the active fermentation, the dangerof oxidation will be small, since the yeast isstill producing large amounts of CO

    2. Col-

    ored fruits often have most of their color inthe skins, so treat them like red grapes.

    A major problem with many fruit winesmade from peaches, apples, apricots, andpears is oxidation. Always use sound fruit andcut out discolored pieces prior to macera-tion. Also add sulfur dioxide at the time ofmaceration (crushing). Using pectic enzymesmay aid in clarification and increase yield.

    Most of these fruits, as well as berries

    and rhubarb, require amelioration (adjust-ing the sugar-acid content) . Therefore,once the juice is obtained, add enoughsugar to adjust the sugar content to 21%to 23%. At this time test and adjust acidityif necessary. For most berries and rhubarbthe juice must be diluted with a 21% to23% sugar solution in order to reduce theacidity. For some of the low acid fruits suchas pears, peaches, and certain apple vari-eties, you may need to add acid. After fer-mentation, acid can be added to tastemuch more readily, since the sugar will notbe present to interfere with the perceptionof acidity.

    Finishing OperationsFinishing OperationsFinishing OperationsFinishing OperationsFinishing OperationsThe finishing operations described here

    are common to all types of table wines. Thefirst racking (siphoning) may occur in thelatter stages of fermentation when a con-

    siderable amount of the yeast has settledout. At this time, siphon the wine abovethe lees (residue in the bottom of the con-tainer) into a clean container, taking careto minimize aeration of the wine (unlesshydrogen sulfide is detected; see Oxidation

    section). An early racking is particularlydesirable if you want to stick (stop) thefermentation before all the sugar is con-sumed. This can result in a small amountof residual sugar. If a totally dry wine isdesired, delay the first racking until thesugar is completely gone (less than 0.5%sugar).2 With some white wines you mayneed to resuspend the yeast by agitationin order to ferment the last remainingsugar. Carefully mix with a clean rod, mini-mizing the amount of air incorporated intothe wine.

    After the fermentation is complete, storethe wine in a cool area. The lower the tem-perature at this point, the better. When yousee that most of the solids have settled out,rack the wine again. Add approximately 25ppm SO

    2to protect against oxidation. Fill

    the containers to the neck to minimize airspace between the stopper and wine. Thisspace should only be large enough to al-low for changes in volume due to tempera-ture fluctuations.

    Repeat the racking operation until veryfew solids continue to settle. Generally, two

    to four rackings over a period of 6 monthswill be adequate. However, you may needto store red wines in large containers for ayear or more before the final f inishing andbottling.

    Commercial wineries often fine theirwines prior to cold stabilization. You mayfind it more convenient to expose the winesto low temperatures (24F to 32F/-4.4Cto 0C) shortly after fermentation. This willaid both in precipitating potassium bitar-trate and in settling out the solids. If youlive in a cool region, you can get the desir-able temperature range by placing the wineoutside in the early winter. After therackings, the wine should be reasonablyclear, although if you shine a light throughthe wine you may see suspended matterat a point perpendicular to the light beam(Fig. 5).

    The fining operation is an attempt to re-

    move this fine colloidal material from thewine. With white wines a treatment of 0.32to 0.64 ounce (9.1 to 18.2 grams) of bento-nite per 10 gallons (37.8 liters) should beadequate to settle out the suspended mat-ter. It may be worthwhile to test, on a small

    scale, different amounts of bentonite in or-der to determine the minimum amountrequired for clarification. Avoid excessivebentonite since it may impart a musty fla-vor to the wine.

    For most red wines, use a protein mate-rial for fining. Use a 1% gelatin solution(prepared by heating 10 grams per 1000milliIiters0.33 ounce per quartof water).The treatment rate should be in the rangeof 0.16 to 0.65 ounce (4.5 to 18.4 grams)per 10 gallons of wine. Add the fining agentduring racking while the wine is being si-phoned into a new container. Once thefloculated material has settled out, imme-diately rack the wine into a clean container.Siphon the residue containing the settled

    Fig. 5. After periodic rackings wine shouldappear reasonably clear. Shining a flash-light through the wine, however, will revealhow much suspended material remains.Fining is the next step.

    2A good method for checking low levels of sugaris to use tablets made specifically for this pur-pose and available from winemaking shops.

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    material into a common container and re-settle it to increase the yield.

    The wine is now ready for aging or bot-tling. Age red wines either in the originalcontainer or in oak wood. The length of timewine is held in the oak wood will depend

    upon condition of the barrel, its age, andsize. Obviously, in a small oak container (lessthan 50 or 55 gallons) the amount of sur-face area to liquid is relatively large and,therefore, it takes a short time to extract oakmaterials into the wine. Also, the wine ab-sorbs oxygen faster. A new barrel containsmuch more oak extractives than an old bar-rel. Therefore, carefully taste the wine peri-odically to determine the rate of pickup ofoak extractives. You dont want to obtainso much of the oak that it detracts from thecharacter of the wine. If the wine is placed

    in oak barrels, keep the container full andsealed so the wine does not become oxidizedor turn into vinegar.

    Aging of red wines is hastened consider-ably by storing at slightly higher tempera-tures (60F to 65F/15.5C to 18.3C). Af-ter the wine is held in the oak barrel as longas necessary, bottle it immediately. The redwine will continue to age in the bottle at arate that depends on the temperature at

    which it is stored. In no case should the tem-perature exceed 65F/18C.

    Clarify white wines and bottle them assoon as possible. Store the wine at a rela-tively cool temperature (preferably below55F/ 12.7C) and allow it to age in the

    bottle. Generally, white wines are short-lived and should be consumed within thefirst year or so after bottling. Store thebottles on their sides or inverted to pre-vent drying of the cork.

    The type of bottle you use can vary con-siderably (Fig. 6). Screw-cap bottles are con-venient and inexpensive, since a corker andcorks are not required. Clean the bottles byscrubbing with a detergent, rinsing with hotwater, and rinsing with a 200 ppm solutionof SO

    2prior to use. Used corks can be uti-

    lized only if they have not been torn up by

    using a screw-type cork puller. Corks in goodcondition are those removed with the two-pronged cork puller (Fig. 7). If you use corks,heat them in boiling water. Boiling has sev-eral functions. First, it moistens and expandsthe corks so they are no longer brittle. Sec-ond, it washes the corks and extracts corkyflavor. Third, it sterilizes them. Inspect newcorks for cork dust or other debris. If sani-tizing with SO

    2, give the corks a preliminary

    washing to remove debris.With both white and red wines at the

    time of bottling, add approximately 25 ppmto 40 ppm SO

    2to scavenge the oxygen

    picked up in the bottling operation.

    SummarySummarySummarySummarySummary

    You can make good, palatable wines iyou take the necessary precautions. Keepsanitation uppermost in mind. Liberal useof scrubbing brushes, detergents, and hotwater along with dilute bleach solutions osulfur dioxide solutions for sanitizing is re-quired to produce consistently good winesPay close attention to the quality of thefruit that goes into the production of thewine, adjust the sugar content, and ame-liorate or adjust the acid so it is within anacceptable range for consumption. Youmust exclude air from your wine. Oxida-tion can rapidly destroy the varietal characteristics of the wine and produce flavorreminiscent of certain sherries. Finallykeep records so you can repeat any suc-cessful procedure and minimize mistakes

    Fig. 7. The two-pronged cork remover. Itstwo prongs grasp the side of the cork without damage.

    Fig. 6. Types of wine bottles. From left to right: sherry, Burgundy, two kinds of Bordeaux,three Rhine or white, and a screw-cap bottle for fruit and berry wines.

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    Additional ReadingAdditional ReadingAdditional ReadingAdditional ReadingAdditional Reading

    Amerine, M. A., and Marsh, G. L. 1962.Winemaking at Home. San Francisco:Wine Publications.

    Fessler, J. H. 1968. Guidelines to Practi-

    cal Winemaking. Oakland: JuliusFessler.

    Taylor, Walter S., and Vine, Richard P.1968.Home Winemaking Handbook.New York: Harper & Row.

    Wagner, P. M. 1976. Grapes into Wine.New York: Alfred A. Knopf.

    AcidityAcidityAcidityAcidityAciditythe quantity of acid, i.e., theamount of the natural acids which givea tart or sour taste to wine or fruit.

    Air trapAir trapAir trapAir trapAir trapdevice which allows carbon di-

    oxide to escape during fermentationand at the same time excludes air fromthe container.

    AmeliorationAmeliorationAmeliorationAmeliorationAmelioration adjusting sugar and/oracid content to improve quality of fin-ished wine.

    Citric acidCitric acidCitric acidCitric acidCitric acida fruit acid commonlyfound in citrus or berries.

    Colloidal materialColloidal materialColloidal materialColloidal materialColloidal materialsmall particles that

    remain suspended in a fluid mediumwithout settling.

    FiningFiningFiningFiningFiningprocess of adding a componentto clear up cloudy wines.

    FlocFlocFlocFlocFloca light fluffy mass formed by the

    aggregation of a number of fine sus-pended particles.

    HydrometerHydrometerHydrometerHydrometerHydrometera sealed glass tube thatfloats in liquids and is used for measur-

    ing specific gravity or density of the liq-uid. Often has graduated scales whichread as percent sugar.

    LeesLeesLeesLeesLeesthe sediment at the bottom of avessel.

    Malic acidMalic acidMalic acidMalic acidMalic acida fruit acid commonlyfound in apples and other tree fruits.

    MustMustMustMustMustunclarified juice.

    OxidationOxidationOxidationOxidationOxidationchemical process in whichwine reacts with oxygen. Process brownswines, and when slow is partially re-sponsible for aging red wines.

    PomacePomacePomacePomacePomacesolid residue of fruit after thejuice has been expressed.

    PpmPpmPpmPpmPpmparts per million.

    Primary fermentation vesselPrimary fermentation vesselPrimary fermentation vesselPrimary fermentation vesselPrimary fermentation vesselcontainerin which juice (or must) is held duringinitial fermentation.

    RackingRackingRackingRackingRackingthe removal of wine from sedi-ment (i.e., lees) by siphoning or pump-ing.

    StickingStickingStickingStickingStickingprocess in which a wine stopsfermenting before all the sugar has beenconverted to alcohol and carbon diox-ide.

    Sulfur dioxide (SOSulfur dioxide (SOSulfur dioxide (SOSulfur dioxide (SOSulfur dioxide (SO22222)))))a gas formed

    when elemental sulfur is burned. SO2

    is

    a selective antiseptic and an antioxidant.

    TanninTanninTanninTanninTannina general term for the compo-nents in wines that impart an astrin-gent and/or bitter taste. In most fruits,tannin is found in the skins, stems, andseeds.

    Winemaking TermsWinemaking TermsWinemaking TermsWinemaking TermsWinemaking Terms

    Winemaking Supply SourcesWinemaking Supply SourcesWinemaking Supply SourcesWinemaking Supply SourcesWinemaking Supply Sources

    Liberty Malt Supply Co.1419 1st

    Seattle, WA 98101

    Jims Home Beverage SuppliesN. 2613 Division

    Spokane, WA 99207

    The Wine Cellar5 N. Front

    Yakima, WA 98901

    Stans Merry Mart733 S. Wenatchee Ave.

    Wenatchee, WA 98801

    Evergreen Brewing Supply12121 NE Northrop Way

    Bellevue, WA 98005

    Arlenes Flowers9th and Lewis

    Pasco, WA 99301

    Arlenes Flowers1177 Lee Blvd.

    Richland, WA 99352-4299

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    Issued by Washington State University Extension and the U.S. Department of Agriculture in furtherance of the Acts of May 8 and June30, 1914. Extension programs and policies are consistent with federal and state laws and regulations on nondiscrimination regardingrace, color, gender, national origin, religion, age, disability, and sexual orientation. Evidence of noncompliance may be reported throughyour local Extension office. Reprinted January 2004. Subject code 660. B.

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