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Wine Instabilities ask the Back to Vintage with Download the 2018 Vintage Catalogue at grapeworks.com.au Wine-Making Wine instabilities - the Additives Cleaning Grapeworks has an extensive Tools range of yeasts, enzymes, tanins, Food Grade malo bacteria and other solids won’t hurt you wine-making additives. Plastic A range of hazes and deposits can form in wine and these can sometimes cause concerns for consumers. The AWRI helpdesk has recently received queries asking if there are any health risks associated with consuming wines affected by hazes or deposits. This column discusses the common Food Grade Polyethylene. instabilities seen in wine and provides reassurance that they do not pose health or safety risks. 225L, 350L, 500L, Ferment 700L, 1000L Vats What are the most common instabilities found in wine? Hazes and deposits in packaged wine consistently make up around 40% of investigations conducted by the AWRI IBC helpdesk. The majority of these are protein, 1000L IBC EVOH oxygen barrier tank with steel pallet and frame. tartrate crystals and wine yeast/bacteria. Bin Liners Grape protein hazes in wine Liners for harvest and fermenting. Packs of 5 or Rolls of 40 units. Wine-grapes contain proteins that Nally Mega Bins persist through the winemaking process Square food grade polyethylene. Solid and vented bins with and can cause hazes in finished wine. optional gal tipping bars. Wineries usually prevent protein hazes by using bentonite fining to remove most of the haze-forming proteins from wine prior to bottling. In some cases insufficient fining can result in residual soluble grape VC Tanks Variable Capacity Tanks proteins remaining in wine, or late copper High quality flat bottom stainless steel VC tanks with floating lid additions to wine before bottling can result and kit. Tanks inner are mirror polished for easy cleaning. in formation of a copper-protein complex, which can come out of solution and form tartrate can also form in some wines with reactions occur following inhalation of Capacity 100L 230L 330L 530L 1000L a haze once the wine is bottled. Similar to high calcium levels. Being non-toxic and yeast in its aerosolised form rather than Diameter mm 470 620 620 750 1020 those in cloudy apple and pear juices, or non-allergenic, tartrates are actually from consuming foods or beverages made Height mm 800 820 1160 1270 1400 cloudy beers and ciders, the ‘solids’ simply commonly used as food additives (such as with the microorganism. Natural wines, or affect the appearance and texture of the cream of tartar used in baking) and pose deliberately unfiltered and unfined wines, Seal Size mm Ø 450 600 600 700 1000 product consumed. These types of proteins no health risks if consumed. often contain residual yeast lees to aid in Outlet mm 12 25 25 25 25 are non-toxic and non-allergenic, and are wine texture. Many other food products Suction Hose Large range of replacement VC seals available. also contain microbiological species, such found in other fruits and vegetables. While Yeast and bacteria 25, 50, 75 & 100mm ø. CALL FOR VC TANKS 1500 & 2000 LITRE. a protein haze, particularly in white wine, Yeast and bacteria are commonly as yoghurts or probiotic milk drinks. may not look attractive, it poses no risks to found in deposits in wine, due either human health. to insufficient filtration or yeast and Fining agents bacterial growth in wine post-bottling. Different types of fining agents can Tartrate crystals Fortunately, the pH, sulfite and alcohol be used when clarifying wine. Many Ferment Covers Crystals of potassium bitartrate (KHT) conditions typically found in wine make it of these are proteins derived from egg, Covertec breathable and non-breathable covers are are one of the most common deposits an environment that is extremely hostile fish, gelatine or milk and as such have found in wine. Grape juice naturally to food-borne pathogenic organisms, potential to cause allergic reactions in ideal for open fermenters. Keep out fruit flies, wasps contains both potassium and tartaric acid, ensuring wine presents a low risk to health some consumers. Research has shown that and contaminants. Complete range of square which associate together to form KHT from a microbiological perspective. Good Manufacturing Practice ensures rectangular and round covers available. crystals. After fermentation, when wine The most common microorganisms that minimal residual protein remains in becomes saturated with KHT at levels detected in packaged wine are the the final wine, at amounts not associated greater than its solubility in an ethanol/ yeast that conducts wine fermentation, with adverse reactions in food allergic water solution, it drops out of solution Saccharomyces cerevisiae, which is consumers. When making wines suitable Aird Cleaning Chemicals as crystals. To a consumer, KHT crystals also used in baking and brewing, and for vegans, winemakers can now choose Clean and sanitise sustainably. Remove wine tartar, colour, neutralise might look like small glass shards in white the bacteria that conducts malolactic plant-based clarifying agents instead of bacteria, microbes, black mould etc. Meets Food Codex, FSANZ & wine. In red wine, they are usually dark fermentation, Oenococcus oeni. These animal-derived products. organic production by OFA. red in colour and could be mistaken for organisms are not harmful to humans residual colour, tannin or even pieces of when consumed. It is also unlikely that For further information about deposits oak/wood. These crystals often dissolve wine consumers with an allergy to baker’s in wine or any other technical matter, Download the 2018 Vintage National 03 9555 5500 upon touch, or, if consumed, present yeast will react adversely to wine, bread please contact the AWRI helpdesk on (08) as a gritty texture. Crystals of calcium or beer, because generally such allergic 8313 6600 or email [email protected] Catalogue at grapeworks.com.au Email [email protected] www.grapeworks.com.au 66 Grapegrower & Winemaker www.winetitles.com.au February 2018 – Issue 649.
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  • CALCIUM STABILITY in a Nutshell ESSENTIAL CHEMISTRY
    CALCIUM STABILITY in a nutshell ESSENTIAL CHEMISTRY Precipitation of calcium tartrate is becoming more frequent all over the world and causing both economic and brand damage that companies should be aware of. The cause of the problem is still unknown but may be found in climate change, viticultural and enological practices or the use of untreated concrete tanks. Whatever the origin, it is important to know how to identify wines that are potentially calcium unstable and how to treat them. Calcium content (0.04 - 0.15 g/L) of wine is 10-20 times lower than potassium. Calcium precipitates mainly as calcium tartrate (CaT). CaT solubility is only 3 times lower at -4°C than at 20°C: cooling has little effect on the rate of CaT precipitation. Potassium bitartrate precipitation does not induce that of CaT. Low calcium content and the presence of inhibiting factors in wine makes the formation of CaT germs that start the crystallization process unpredictable. WINE COMPOUNDS THAT HAVE AN INHIBITING EFFECT ON CALCIUM PRECIPITATION GLUCONIC ACID MALIC ACID CITRIC ACID COLLOIDS POTASSIUM MAGNESIUM MAIN FACTORS PROMOTING CaT PRECIPITATION CALCIUM LOW HIGH INSTABILITY TARTARIC ACID INSTABILITY pH The main factors promoting calcium precipitation are calcium, pH and tartaric acid. In particular, pH has a tremendous impact. The increase of only 0.1 points has a dramatic effect on the speed and intensity of precipitation. HOW TO RECOGNIZE CALCIUM TARTRATE PRECIPITATE Both CaT and potassium bitartrate form white (or red in the case of red wine) crystals and a sandy precipitate. To distinguish one salt from the other, perform the following trial put some crystals in a flask or beaker add some clean water warm the solution between 80-100°C stir occasionally If crystals do not dissolve, it is calcium tartrate ENARTIS SOLUTION FOR CALCIUM STABILITY HOW TO CHECK IF WINE IS CALCIUM UNSTABLE Analyze wine calcium content (Ca1).
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  • Things We're Dwelling on Now… Cold Stabilization
    Grape Resources www.fruit.cornell.edu/grapes Things We’re Dwelling on Now… Cold Stabilization Chris Gerling, Enology Extension Associate, Cornell University - NYSAES First published in Cellar Dweller - January 2010. Cold stabilization time is here for many of us. When you think about it, cold stabilization shares with all winemaking the principle that bad results are unlikely to hurt anyone, but you can definitely upset people. Here are some tips to keep in mind when attempting to get the “wine diamonds” out before they show up at a dinner party. Faster chilling is better. For quicker and more complete precipitation, changing the temperature drastically is the best way to shake those crystals loose. Seeding with potassium bitartrate and agitating the wine can speed up the process further. Stabilization can still take place with traditional chilling and higher temperatures, but the process will take more time. Chilling is only effective on potassium bitartrate. In a year where a lot of deacidification took place, a fair amount of calcium carbonate was most likely used. Calcium tartrate is NOT responsive to temperature like potassium bitartrate is. The standard conductivity and freeze tests are also not effective in determining stability. What conditions do affect calcium tartrate? Alcohol, pH and the presence of sugars and acids all play a role in both potassium and calcium tartrate precipitation. As a general rule, higher alcohol and higher pH will favor precipitation, while organic acids and sugars seem to inhibit it. Malic acid seems more inhibitory than lactic, however, so malolactic fermentation can be considered as a step towards precipitation, especially when the pH bump is considered.
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  • Tartaric Acid Handling 1 2 Identification of Petitioned Substance
    Tartaric Acid Handling 1 2 Identification of Petitioned Substance 3 Chemical Names: 14 4 2,3-dihydroxybutanedioic acid CAS Numbers: 5 L(+) tartaric acid: 87-69-4 6 Other Name: D(-) tartaric acid: 147-71-7 7 2,3-dihydroxysuccinic acid Mesotartaric acid: 147-73-9 8 Thearic acid Racemic acid: 133-37-9 9 Uvic acid 10 L(+) tartaric acid Other Codes: D(-) tartaric acid L(+) tartaric acid: 205-695-6 Mesotartaric acid D(-) tartaric acid: 201-766-0 Racemic acid Mesotartaric acid: 205-696-1 Racemic acid: 205-105-7 11 Trade Names: 12 None 1513 Characterization of Petitioned Substance 16 17 Composition of the Substance: 18 Tartaric acid [HOOCCH(OH)CH(OH)COOH; C4H6O6] is a four-carbon, organic acid with two OH groups 19 on the second and third carbon atoms, and two carboxylic acid (COOH) groups involving the first and 20 fourth carbons. The chemical structure of L(+) tartaric acid is shown below: 21 22 Source: Reusch, 1999 23 24 Tartaric acid exists in three distinct isomeric forms, as shown in the Fisher projection formulas below. Two 25 forms are chiral isomers, which means that the molecules are non-superimposable on their mirror images. 26 The form of tartaric acid found naturally in grapes and often produced synthetically for use in handling is 27 the L(+) tartaric acid isomer. This form is generally referred to as the ‘dextro form’ (Church and Blumberg, 28 1951). The D(-) form of tartaric acid is less common in nature and has almost no practical uses. The third 29 form is an achiral isomer, mesotartaric acid, that also can be manufactured (Reusch, 1999).
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  • The Production and Action of a Tartrate Decomposing
    THE PRODUCTION AND ACTION OF A TARTRATE DECOMPOSING ENZYME DISSERTATION Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By RICHARD RUSSELL BARTON,i' B.S., M.S„ XX-XXX The Ohio State University 1 9 5 2 Approved by: ACKNOWLEDGMENT The author ■wishes to express his appreciation to the following men for their help and guidance: Drs. Howard D. Brown aid Freeman S. Howiett of the Department of Horticulture, The Ohio State University and The Ohio Agricultural Experiment Station for their help and criticisms in preparing this manuscript. Dr. William D. Gray of the Department of Botany, The Ohio State University for his helpful suggestions during the course of this work and for supplying a strain of fungi used in this work. Dr. Richard S. Davidson formerly of the Department of Botany and Plant Pathology, The Ohio Agricultural Experiment Station for his many helpful suggestions and for treating fungi with radio-active materials. ii £09371 TABLE OF CONTENTS page Introduction .......................................... 1 Review of Literature .................................. 3 Methods and Materials ................................. 28 The ability of fungi to utilize tartrates ......... 28 Growing fungi for production of tartrase ............ 28 Extraction and preparation of a tartrase preparation ... 30 Separation and culture of single spore isolates ...... 31 Testing the activity of tartrase produced by different strains of Aspergillus versicolor ................. 33 Relationship between constituents of media and tartrase activity ................ 3^+ Relationship between metallic ions added to substrate and tartrase activity ............................ 35 Relationship between external factors and tartrase activity........................................ 36 Determination of enzymatic breakdown products of tartaric acid .............................
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  • Calcium and Its Unpredictable Presence
    ask the Calcium and its unpredictable presence Earlier in the year this column featured KHT deposits and cold stability. This month the focus is shifting to calcium instabilities, another type of deposit seen quite commonly by the AWRI helpdesk. CALCIUM-INDUCED INSTABILITIES continue to be a problem for winemakers. While there are many types of calcium deposits that can arise in wines such as calcium DL-tartrate, Calcium L-tartrate deposits can calcium oxalate, calcium sulfate and calcium mucate, it is be a frustrating problem for calcium tartrate, or more importantly crystals of calcium L-tartrate, which the AWRI helpdesk sees most often. winemakers because the crystals are slow to form and usually do not Q. HOW CAN I TELL IF MY WINE IS AT RISK OF THROWING A CALCIUM TARTRATE DEPOSIT? come out of solution for some time, Knowing the concentration of calcium in wine will give often months, after bottling. an understanding of the risk of calcium instability. Calcium deposits are often seen in wines where calcium concentrations exceed 60 mg/L for red wines and 80 mg/L for white wines. If a wine has calcium levels close to or above those levels, Q. WHAT HAPPENS TO CALCIUM TARTRATE DURING then other factors that may increase pH, such as malolactic COLD STABILISATION? fermentation and blending, can also increase the likelihood of Unlike for potassium bitartrate, temperature has little effect calcium L-tartrate precipitation. on the rate of calcium L-tartrate precipitation and therefore there is no predictive test for calcium L tartrate instability. Q. WHY IS MY WINE HIGH IN CALCIUM? This fact means that simple cold tests are ineffective The calcium content in grapes will vary from year to year indicators of calcium L-tartrate instability and cold stabilisation and from vineyard to vineyard.
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  • Acid Reduction Techniques in Must and Wine
    Ohio Agricultural Research and Development Center _________________________________________________________________________________________________________________________________ Horticulture and Crop Science 1680 Madison Avenue Wooster, OH 44691-4096 Phone: (330) 263-3878 Williams Hall Fax: (330) 263-3887 Williams Hall (330) 263-3685 Gourley Hall Acid Reduction Techniques in Must and Wine Todd Steiner Enology Outreach Specialist The Ohio State University/OARDC Department of Horticulture and Crop Science Wooster, OH Since each harvest year is different, the winemaker must be able to adapt his vinification practices in achieving a well balanced wine. Excess acidity at harvest may occur in cool climate viticultural areas such as it does in the Northeastern United States and Canada. Wine acidity is responsible for freshness, tartness and crisp taste. Wines of high acidity may appear to be very tart or acidic whereas wines of low acidity may appear flat or insipid. Therefore, it is vital to develop a wine that has a good balance with acid being a major factor. The predominate acids found in must and wine are tartaric and malic acid often accounting for over 90 percent of the total acids found in grapes with citric acid considerably lower in concentration (1). Other organic acids formed mainly during fermentation at different levels would include acetic, succinic and lactic acids (2). In determining correct acid concentrations in wine one must not make acid adjustments based on the titratable acidity and taste alone. It is vital to examine juice and wine acids and their direct effect on pH. Monitoring juice pH is important to help determine ripeness of the grape, wine color, chemical and microbial stability.
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  • Re‐Evaluation of L(+)‐Tartaric Acid (E 334), Sodium Tartrates
    SCIENTIFIC OPINION ADOPTED: 29 January 2020 doi: 10.2903/j.efsa.2020.6030 Re-evaluation of L(+)-tartaric acid (E 334), sodium tartrates (E 335), potassium tartrates (E 336), potassium sodium tartrate (E 337) and calcium tartrate (E 354) as food additives EFSA Panel on Food Additives and Flavourings (FAF), Maged Younes, Gabriele Aquilina, Laurence Castle, Karl-Heinz Engel, Paul Fowler, Maria Jose Frutos Fernandez, Peter Furst,€ Rainer Gurtler,€ Ursula Gundert-Remy, Trine Husøy, Wim Mennes, Romina Shah, Ine Waalkens-Berendsen, Detlef Wol€ fle, Polly Boon, Paul Tobback, Matthew Wright, Jaime Aguilera, Ana Maria Rincon, Alexandra Tard and Peter Moldeus Abstract The EFSA Panel on Food Additives and Flavourings (FAF) provides a scientific opinion on tartaric acid- tartrates (E 334-337, 354) when used as food additives. The Scientific Committee for Food (SCF) in 1990 established an acceptable daily intake (ADI) of 30 mg/kg body weight (bw) per day, for L(+)- tartaric acid and its potassium and sodium salts. The metabolism of L(+)-tartaric acid and its potassium sodium salt was shown to be species dependent, with a greater absorption in rats than in humans. No toxic effects, including nephrotoxicity, were observed in toxicological studies in which the L(+)-form was tested. There was no indication for a genotoxic potential of tartaric acid and its sodium and potassium salts. In a chronic study in rats, no indication for carcinogenicity of monosodium L(+)- tartrate was reported at the highest dose tested (3,100 mg/kg bw per day). The available studies for maternal or developmental toxicity did not report any relevant effects; no studies for reproductive toxicity were available; however, no effects on reproductive organs were observed in the chronic toxicity study.
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  • Bitter Orange (Citrus Aurantium Var
    Bitter Orange (Citrus aurantium var. amara) Extracts and Constituents (±)-p-Synephrine [CAS No. 94-07-5] and (±)-p-Octopamine [CAS No. 104-14-3] Review of Toxicological Literature June 2004 Bitter Orange (Citrus aurantium var. amara) Extracts and Constituents (±)-p-Synephrine [CAS No. 94-07-5] and (±)-p-Octopamine [CAS No. 104-14-3] Review of Toxicological Literature Prepared for National Toxicology Program (NTP) National Institute of Environmental Health Sciences (NIEHS) National Institutes of Health U.S Department of Health and Human Services Contract No. N01-ES-35515 Project Officer: Scott A. Masten, Ph.D. NTP/NIEHS Research Triangle Park, North Carolina Prepared by Integrated Laboratory Systems, Inc. Research Triangle Park, North Carolina June 2004 Abstract Citrus aurantium (bitter orange, Seville orange, sour orange) and extracts of its dried fruit and peel have been used for years in traditional Western medicines, Chinese and Japanese herbal medicines, and as flavorings in foods and beverages. Bitter orange is regulated by the U.S. FDA; the peel, oil, extracts, and oleoresins are Generally Recognized as Safe as a direct additive to food. The peel is used in many pharmacopoeial preparations for flavoring and treatment of digestive problems. Oils from the fruit, peel, and other plant parts are also used for flavoring and fragrance and do not contain alkaloids. p-Octopamine and p-synephrine, the most frequently mentioned biogenic amines found in bitter orange extract, are agonists for both a- and b-adrenoceptors (octopamine has weak b-adrenergic activity). Octopamine is used as a cardiotonic and to treat hypotension. Synephrine is used as a vasoconstrictor in circulatory failure.
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  • Potassium Sodium Tartrate
    SAFETY DATA SHEET L(+) POTASSIUM SODIUM TARTRATE Section 1: Identification of the Substance and of the Company 1.1 Product Identifier: Product Name: Rochelle Salt (Potassium Sodium Tartrate) Synonyms: Rochelle Salt; Seignette Salt; Sodium Potassium Tartrate; 2,3- dihydroxy-[R-(R*,R*)]-butanedioic acid, monopotassium monosodium salt tetrahydrate CAS Number: 6381-59-5 (Tetrahydrate); 304-59-6 (Anhydrous) EINECS: 206-156-8 E Number: E337 REACH Registration: 01-2119524666-34-0002 Molecular Weight: 282.22 Chemical Formula: KNaC4H4O6 . 4H2O 1.2 Relevant Identified uses of the Substance and Uses Advised Against: Relevant Identified Uses: As additive in food industry, in plating industry, in the preparation of cigarette paper, in the mirror industry, as additive for gypsum and cement, for pH correction, as metal cleaner, for preparation of Fehling reactive, as complexant agent 1.3 Details of the Supplier of the Safety Data Sheet: Supplier: ATPGroup, Inc. 2 Madison Ave. Larchmont, NY 10538 USA Telephone: 914-834-1881 Fax: 914-834-4611 www.atpgroup.com 1.4 Emergency Telephone Number Telephone 800-424-9300 – CHEMTREC (24/7) – within USA & Canada +1 703-527-3887 – CHEMTREC (24/7) – International & Maritime 914-834-1881 – ATPGroup Page 1 of 9 Section 2: Hazards Identification 2.1 Classification of the Substance: Classification according to Reg. EC 1272/2008 Classification according to Reg. EC 67/548 Not classified as dangerous Not classified as Dangerous Precautionary: P261: Avoid breathing dust Safety Phrases: S1/2: Keep locked up and out of P262: Do not get in eyes, on skin, or reach of children. on clothing. S22: Do not breath dust P280: Wear protective gloves, S37/39: wear suitable gloves and protective clothing, eye protection, eye/face protection.
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  • KHT Deposits and Cold Stability
    ask the KHT deposits and cold stability POTASSIUM BITARTRATE (KHT) is the crystalline Figure 1 shows the distribution of the tartrate species as a substance that drops out of solution when a wine is cold function of pH. The maximum concentration of HT- (which stabilised. However, if cold stabilisation is unsuccessful, wines can precipitate as KHT) occurs between pH 3.6 and 3.7, can end up with KHT deposits after packaging and these depending on the alcohol concentration, and this is the point represent around 25-35% of the AWRI helpdesk’s haze/deposit at which precipitation will be greatest. Consequently, any wine investigations each year. So why does this type of deposit treatments that might change a wine’s pH, such as blending, continue to be an issue for the wine industry? One reason is acid additions or malolactic fermentation, could affect KHT that there is no universal definition of ‘cold stability’, so a wine precipitation. If a wine has been ‘cold stabilised’ prior to such might pass one type of ‘cold stability’ test yet fail another. A treatments, cold stability checks must be conducted again second reason is that wines contain a range of compounds that before bottling. can inhibit KHT crystallisation, and these can change over time, such that they no longer inhibit crystallisation. This can WHY DOES WINE PH SOMETIMES CHANGE DURING lead to precipitation of tartrates in wine previously thought to COLD STABILISATION? be cold stable. This is a common question, but one that is hard to answer in just a few words. A detailed explanation of this phenomenon is SO WHAT EXACTLY IS ‘COLD STABILITY’? available on the AWRI’s website under the heading ‘Potassium Cold stability can be described as a wine’s tendency to instability’ in the Winemaking/Instabilities section (or enter precipitate KHT crystals when exposed to low temperature.
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  • Potassium Bitartrate Stabilization of Wines
    Zoecklein and Fugelsang POTASSIUM BITARTRATE STABILIZATION OF WINES Learning Outcomes: Bitartrate stability and determining the optimum method(s) to use require and understanding of time, energy, water, water composition, waste and recovery, and the impact on wine sensory features. The reader will understand the practical considerations influencing crystal formation, bitartrate stabilization and evolution of wines Chapter Outline BZ correct Potassium Bitartrate Instability Complexing Factors Electrodialysis Addition Compounds for Potassium Bitartrate Stabilization Fining and Bitartrate Stability Determining Potassium Bitartrate Stability Cellar Considerations for Contact Seeding Section 1. Wine instability can be classified as one or more of the following: microbiological protein Zoecklein and Fugelsang tartrate red wine oxidative and color white wine oxidative and color metals The problems of producing stable, highly palatable products are of concern to every vintner. The days when wineries can release wines to the public with physical instabilities, and still compete, have passed. Therefore, it is essential that every vintner understand the parameters affecting wine stabilities, and operate to obtain product stability while maximizing palatability. Bitartrate Instability Tartaric acid (H2T) and its salts, potassium bitartrate (KHT) and calcium tartrate (CaT), are normal constituents of juice and wines and important to stability. The formation of crystalline deposits is a consequence of wine chemical and physical properties as well as aging. In that crystalline deposits generally do not meet with consumer acceptance, most winemakers strive to reduce the potential for post-bottling formation. The tartaric acid content of grape must/juice ranges from 2.0 to 10 g/L and varies by region, variety, maturity, soil, and viticultural practices.
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  • Tartrate Removal Methods in Wine and the Role of Conductivity
    Tartrate Removal Methods in Wine and the Role of Conductivity YSI Tartrates in Wine Application Note A537-02 Tartrates are naturally occurring crystals that often form in wines and may be considered undesirable to most customers. To most people, tartrates resemble small pieces of cut glass or diamond like crystals that form on the cork and as sediment in the wine bottle. The crystals are formed from potassium bitartrate, a naturally occurring organic acid, which is found in many plants including grapes. Tartaric acid actually plays two important roles in the winemaking process by keeping pH low enough to prevent spoilage bacteria from growing and to act as a preservative after fermentation. The YSI 4010-1 is a one-channel instrument ideal for high quality conductivity To most wine enthusiasts, tartrate crystals pose no serious measurements for routine sampling as part of the problem. They are, in fact, considered to be part of a quality winemaking process. wine that hasn’t been overproduced. Even though tartrate crystals are harmless, their presence may lead to a more and electrodialysis have been used to remove these “tart” tasting wine that is less desirable to some enthusiasts. unwanted crystals. In this process, an electric current attracts Customers have been known to return shipments of good the potassium and bitartrate ions, yet leaves the colloidal wine that have the presence of these crystals. structure intact. This method can be more complicated since it utilizes sophisticated equipment and conductivity testing Processes for tartrate removal are cold stabilization, chemical instruments along with process controllers. The scope of this additives or grape/vine management practices.
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