Skip to content
Free Shipping on Most Orders over $59. Learn More »
Free Shipping on Most Orders over $59. Learn More »

Wine Maker’s Glossary of Chemicals and Additives

Compiled by Don Schiller & The Purple Foot Wine Club

Most wine making chemicals have a limited shelf life. Our best advice is: buy chemicals for the quantity of wine you are making, or at the most enough for one season and properly dispose of them after the season is done. Start out fresh next year.

All measurements where provided below are approximate and may differ between brands. See package directions for full information.


acid blend – a mixture of tartaric, malic and citric acids used in wines requiring additional acid. Test the acid level before adding any kind of acid.

acidity – the desirable acidity of a wine depends on the style. Dry white table wine should be between 0.65 -0.75% titratable acidity (TA) Dry red table wine should have a T.A. of 0.60% - 0.70%. Sweet white table wine should be between 0.70% - 0.85%. Semi-sweet table wines and ports should fall between 0.65% - 0.80%. Sherries should be between 0.50% and 0.60%. Fruit and sparkling wines should have the same acidity as a similar grape table wine.

ascorbic acid – an antioxidant or anti-browning agent used in making apple wine. This is not vitamin C tablets.

bentonite – fining agent made primarily of clay. May reduce the color in red or ros wines. Harder to work with than some other fining agents. Mix in blender with water. Let stand 24 hours, shake well, then add to wine. Use 1-2 teaspoons in a 5-gallon batch.

Brix – in simple form, Brix is a hydrometer scale used to measure the sugar content of a solution at a given temperature. Starting Brix when making wine is about 21 degrees depending on wine type.

calcium carbonate or precipitated chalk – used to reduce acid in wines or must. Reacts more with tartaric acid. Does not cold stabilize well. May leave a taste in the wine. Generally not suggested for use if alternates can be used. 3.8 grams per gallon, 19 grams for 5 gallons, 3 teaspoons for 5 gallons.

Campden tablets – an easy-to-use additive that helps prevent oxidation. Usually one or two crushed tablets are used per gallon to sterilize must (wait 24 hours before adding yeast). Can use one crushed tablet per gallon at each racking. Always dissolve before stirring in must or wine.

carbon dioxide or CO2 – carbon dioxide is a gas produced by the process of yeast converting sugar into alcohol. As the CO2 is produced it rests on the surface of the wine, helping to prevent oxygen from getting into the wine. CO2 is also used to top off wine, the process of adding CO2 to the top of the carboy to replace oxygen that may have gotten into the carboy. CO2 is also used by some wine makers to move the wine when racking, or to push the wine when filtering.

citric acid – helps prevent iron hazes. 1 teaspoon equals 4.3 grams.

cold stabilization – cold stabilizing reduces the acid level and will reduce or prevent crystals from forming when cooling wine in the refrigerator. Keeping wine at 35 degrees for two weeks will drop out tartaric acid in the form of crystals, reducing the acid level of the wine. Keep wine dark.

copper sulfate – used to remove hydrogen sulfide (H2S) from wine. Use when fermentation is finished, but only as a last resort if racking wine does not eliminate the problem.

filtering – filtration removes fragments of fruit, possible bacteria, and yeast cells. This cleaning process helps to improve taste, appearance and durability. Filtration enhances the quality of the wine. Filtration is commonly done by pressing the wine through filter pads that retain the solids. Many different types of filter systems are available.

fining – clearing the wine by chemical or non-mechanical means. Certain types of cloudiness or haze may appear in wine, and each type has an additive that works to clear the haze. Types of common fining agents include bentonite and Sparkolloid. Egg whites have also been used in fining wine.

gelatin – fining agent that reduces tannins and astringency. Can over strip. Use 1 package or less dissolved in water.

glycerin – if the wine is thin, a couple ounces of glycerin give the impression of a wine with more body. Glycerin will also add some sweetness to wines. It can be used with sugar syrup to sweeten wine.

hydrogen sulfide – a gas produced by yeast causing a rotten egg smell that is often produced at warmer fermentation temperatures. Often removed by racking the wine. If severe, can be removed by copper sulfite as a last resort.

hydrometer – a glass bulb device used to measure the specific gravity (SG) of juice or wine. The sweeter the liquid, the higher the hydrometer will float and the higher the specific gravity. A wine making hydrometer has three scales: specific gravity, Brix and potential alcohol. The suggested starting point for Brix is about 21; specific gravity is about 1.085. This will give you a wine of about 12% alcohol. The desired finished wine will be your guide for the actual starting level.

isinglass – gentle fining agent that settles yeast in white wines. Doesn't work in reds. Use 4 ounces of liquid isinglass for a 5-gallon batch.

malic acid – found naturally in apple wine, it is generally not used as an additive in most wines unless as part of an acid blend. It is most susceptible to problems like malolactic fermentation.

oak chips or shavings – oak chips and shavings add an oak flavor to wines and are used instead of oak barrels. Use about 3 ounces of chips per 5 gallons of wine. Put chips in a nylon bag with a weight to hold the chips in the wine. Chips produce the greatest oak flavor in the first week, but can be left in longer for additional oak flavor and tannin.

oxygen or oxidize –a gas that readily combines with wine and chemicals, in most cases causing a bad reaction. When combined with wine, the wine oxidizes, may take on a brown color, and will deteriorate. There are several ways to keep wine from oxidizing, including (but not limited to) the use of ascorbic acid, carbon dioxide for topping off the carboy, using SO2, metabisulfite or Campden tablets. When oxygen mixes with chemicals, it generally reduces the strength of the chemicals, causing them to be less effective. Try to keep oxygen away from chemicals by keeping the cap tight.

pectic enzyme – used when starting wines, this enzyme helps break down pulp, clears pectic haze, and helps extract color from grapes and fruit. This has been a powder in the past but is now available in liquid form. If you have the powder, use 2.5 teaspoons per 5 gallons. The liquid may differ in drops per gallon, so read instructions. Use the recommended amount when using a recipe.

polyclar – fining agent that reduces tannins and some browning. 1 teaspoon equals 0.9 grams. Use 1-3 grams per gallon, or 0.25 ounces of liquid for 5 gallons.

potassium bicarbonate – used to reduce acid in wines or must. Works well with cold stabilizing. 1 teaspoon equals 6.1 grams.

potassium bitartrate (cream of tartar) – promotes better cold stabilization at higher temperatures. Use 3.4 grams per gallon or 1 teaspoon per gallon and stir hard for 0.1% acid reduction.

potassium metabisulfite or 57% sulfur dioxide (SO2) – use at start of must, at each racking, and at bottling. Do not add during fermentation. Prevents molds and bacteria, helps prevent oxidation, and is used to clean and sterilize wine bottles. It has a limited shelf life. Add 1/4 teaspoon to 5 gallons of wine for 50-75ppm mixture.

potassium sorbate – a yeast inhibitor that keeps wine from refermenting after sugar is added at bottling. Keep away from light. Shelf life is about 1 year. To be used with potassium metabisulfite. Use 2.5 teaspoons for a 5-gallon batch.

racking – the process of removing sediment from the wine. This is generally done by siphoning the wine, leaving the sediment behind. The first racking should be when the specific gravity is about 1.010-1.005. Rack from the primary fermenter into the secondary fermenter. After that, racking should be done after the wine has cleared for 3 weeks or 1-2 weeks after adding Sparkolloid. As a rule, add 1/4 teaspoon of metabisulfite to the wine at each racking.

Sparkolloid – good general fining agent. Hot mix. Mix with water and boil for about 30-45 minutes. Add water as needed. Mix with wine while hot. Wine should clear in about 1-2 weeks. May not be desired in some red wines. Use 1 teaspoon per gallon.

specific gravity or SG – ratio of mass of a liquid to the mass of distilled water. The specific gravity scale on a hydrometer is used to measure the sugar content or sweetness of a juice or wine.

sugar – if juice has a low Brix, it should be brought up before starting fermentation. This can be done by adding sugar. Add 1.5 ounces of sugar per gallon to increase Brix 1 degree. Add 7.5 ounces or about 1/2 pound sugar for 1 degree Brix increase in 5 gallons. 5 pounds of sugar will increase Brix about 10.7 degrees. These figures are approximate. Measure with a hydrometer.

sugar syrup – used to sweeten wine before bottling. 2 parts sugar to 1 part water. Heat mixture to make a syrup consistency and let cool completly before adding. Be sure to add potassium sorbate to sweetened wine.

tannic acid or grape tannin – tannin is found naturally in grapes and is made from powdered grape skins. Tannin is needed in apple wine and some whites. Use 1/4 - 1/2 teaspoon per 5 gallon.

tartaric acid – this is most the predominant acid in grapes and it is the most stable acid. It is usually added for flavor, color and stability. Use when making fruit wines. 1 teaspoon equals 4.8 grams.

topping off –adding wine, water, CO2, or even marbles will reduce the open space in the top of a carboy where oxygen can come in contact with the wine. Topping off with water will dilute wine. Before topping off any wine, seek advice from a wine maker or your local brew shop.

yeast – wine yeast is specially developed for making wine. Several types of wine yeasts are available; each produce a different effect in the wine. Wine yeast is more tolerant of SO2 than is wild yeast.

yeast nutrient – used to aid yeast growth during fermentation. Urea and di-ammonium phosphate are two types of nutrients. The quantity depends on the nutrient used.