Wines at home FAQ

Here you can find answers to questions about how the board works. Use the links or search box below to find your way around.


An oxidation product of ethyl alcohol. A fault when sensed in table wines and beers, but acceptable as an ingredient in the bouquet of sherry or Madeira. It may be recognised by its sharp, penetrating colour.

Acetic acid

The acid that makes vinegar.


The formation of vinegar, usually caused by contamination of the must, liquor or finished product with vinegar-producing bacteria (acetobacter) and the presence of air. Fermentation bottles should be filled as high as the froth or foam caused by fermentation will allow and the topped up as foam production subsides. Stored wine should have no more than one inch of air under the cork in the standing bottle (2/8 to 1/2 inch is preferred). Adding one Campden tablet per gallon (or 5ml 10% sulphite solution) may halt acetification in its early stages, when the wine emits a slight smell of vinegar and an acid taste. When the smell of vinegar is strong, however, it is probably too late to save the wine, but you might want to go ahead and make some wine vinegar instead. NEVER make wine in a wooden cask or barrel or plastic primary that has contained vinegar, even if acetification was successfully halted.

Acid Blend

A blend of acids important to wines, usually tartaric, malic and citric acids. While there are many different formulations of acid blend, the recipes on this site calling for acid blend assume a blend of 50% tartaric, 30% malic and 20% citric. If your acid blend uses a different ratio, you may want to use slightly more or less depending on your blend


The amount of acid in the must, liquor, or finished wine. Insufficient acidity in the must will result in a poor fermentation and a slightly medicinal and flat taste. Too much acid will give the wine an unpleasant sourness or tartness. Some acid is necessary for fermentation, and up to one-fourth of the initial acid content will be consumed by the yeast during fermentation. Low-acid musts are usually corrected by adding tartaric acid (the principal acid in grapes), malic acid, citric acid, or acid blend. An acid testing kit is indispensable in measuring initial acidity. Getting the level of acid right is critical if quality wines are to be produced. CLICK HERE FOR TUTORIAL

Activated Yeast

A hydrated, feeding, reproducing colony of yeast. The colony may have formerly been stored as active dry yeast (ADY), as a dense liquid colony under refrigeration, as dried yeast on grape skins and pulp, or in several other forms. See tutorial section for information on Yeast Starters.

Aerobic Fermentation

A fermentation conducted in the presence of Oxygen, as in a crock, vat, tank, or polyethylene pail. Aerobic conditions are necessary for yeast to rapidly reproduce to a density conducive to the fast production of alcohol.


After the fermentations are done, the wine is put aside in bulk or bottles to age. During this time, a redox reaction occurs to improve the wine.


A simple device that looks like a wide letter 'S' laying on its side (this is the standard form, there are others). It is filled with enough water such that air or contaminants cannot flow through it back into the wine while allowing the pressure from fermentation gases (primarily CO2) to push out. These are also known as fermentation locks.


Adding water, sugar and chemicals to the must in order to make a better wine.

Amyl acetate

An ester formed from amyl alcohol and acetic acid having the odour known as 'peardrops'. It is normally present in very small quantities in wines and beers. An indication of acetification when present to any consideralbe extent.


An enzyme that hydrolyzes starch to produce dextrins, maltose, and glucose.

Anaerobic Fermentation

A fermentation conducted in the absence Oxygen, as in a fermentation bottle, jug or carboy fitted with a fermentation trap.


A wine made for increasing the appetite.

Ascorbic acid

Vitamin C. Present in fruits, vegetables and honey. Sometimes used as an antioxidant in wine, but, unlike sulphur dioxide, does not prevent bacterial spoilage.


The effect of tannin on the mouth; it causes the mouth to pucker and leave a "dry" feeling in the mouth. Felt along the edges of gum and teeth and on the rear portion of the tongue.


A scale to show how much sugar is present in must. Interchangable with Brix


A type of finely ground clay that is used as a clarifying agent. It is used at varying stages of the process, including at the beginning to provide something to which yeast can attach themselves to improve growth and help clear out solids from the primary fermentation. In order to maximise bentonite's effect, it should be dissolved in 3-5 times its own volume of water. Stir gently, and leave to swell for a while (6-12 hours). Pour off the excess water and dilute again with a little of the wine to be fined. Stir well and mix the solution thoroughly with the entire quantity of must/wine to be fined.


The process of combining different wines to create a composite that's better than any of the wines separately. The wines blended might be from different varieties, different regions, different wood- and non-wood-aging, different vintages, and even wines made from different fruit. CLICK HERE FOR BLENDING TUTORIAL


The thickness of the liquid wine in your mouth.


The most common wine bottle size worldwide is 750 ml, but it is not standard. Some German wine bottles are a liter, some are 700 ml, while some from Alsace are 720 ml. Every wine bottle consists of a mouth, neck, ogive or shoulder, body, and bottom. The bottom may contain an indention, the term for which is a punt. Some almost standard names for different size wine bottles are: Split (Sparkling): 187 ml Half-Bottle: 375 ml Bottle: 750 ml Magnum: 1.5 litres Tregnum: 2.25 litres Double-Magnum: 3 litres (Bordeaux shaped) Jeroboam (Sparkling): 3 litres (Burgundy shaped) Jeroboam (Still): 4.5 to 5 litres (Bordeaux shaped) Rehoboam: 4.5 litres Imperial (Still): 6 litres (Bordeaux shaped) Methusalah (Sparkling): 6 litres (Burgundy shaped) Salmanazar: 9 litres (Bordeaux shaped) Balthazar (Sparkling): 12 litres (Burgundy shaped) Nebuchadnezzar (Sparkling): 15 litres (Burgundy shaped) Soverign: 50 litres CLICK HERE FOR BOTTLING TUTORIAL

Bottle Sickness

A period following bottling during which the wine is flat, uninspiring and possibly unpalatable. This is a temporary condition which usually lasts no longer than a month and rarely two.

Bottling tree

Bottle drainer. For draining washed bottles. Can be enlarged easily using extra screwable elements. A plastic construction that holds usually up to 80+ bottles with necks facing downwards, to aid in drying.


The scent of the wine when you open the bottle.


An alcoholic beverage made with malt and honey; thus it bridges the gap between mead and ale.


A heating belt that keeps wine from becoming too cold in colder months. Warming plates are equivalent. The plates cause a temperature rise of ± 6°C, and are constructed to keep the wine in winter on a temperature suitable for fermentation


A measurement of sugar content in a must. Degrees Brix, as measured on your hydrometer, is very close to percent sugar and is most easily considered as such. Conversion of sugar to alcohol is usually in the range of 0.52 to 0.59.


Rubber or silicone stopper. Bungs fit in the neck of the demijohn and can be used to seal them off with an airlock. Come in variety of sizes.

Calcium Carbonate

Food grade chalk used to counter over-acid wines. Two teaspoons per 4.5 liters will reduce the acidity by 0.1 percent - 0.15 percent. Use no more than six teaspoons per 4.5 liters.

Campden Tablets

Tablets of a standard amount of compressed sulphite. It usually has a mass of about either 0.44g or 7 grains, roughly equivalent to about 0.28g SO2. I tablet to a Uk gallon is equivalent to 50ppm.


The vegetable matter and foam layer that forms on the top of the wine during the first few days of fermentation. Although your fermenting wine may break it up and absorb it eventually, it is best to manually break it with your wine stirrer/spoon as often as it forms to avoid the production of off smells and problems with overflowing as well as to maximize colour and flavour extraction.


To add sugar to a must or juice to increase its alcohol potential, or to a new wine to balance the taste of its alcohol or the bite of its acidity or tannin. The word is a methode named after M. Chaptal, who in 1801 accurately calculated the amount of sugar to add to a wine to achieve balance.

Chateau bottled

Bottled at the house or place where the wine was made.

Citric acid

The acid most commonly present in citrus fruits, used to acidify and help preserve wines.


The process of letting the wine "settle" or clear itself of minute particles. see also hazes


The feel in the mouth of excessive sweetness, especially in the after-taste.


The colorless, odorless gas emitted by yeast during fermentation. During Aerobic Fermentation, the gas fills the Ullage but does not completely prevent desired oxygen from entering the Must. During Anaerobic Fermentation, the gas fills the Ullage but the Air Lock prevents undesired oxygen from entering the must. An Air Lock allows carbon dioxide to escape without allowing oxygen into the fermentation vessel. The chemical shorthand for carbon dioxide is CO2.

Cold Stabilisation

The process of removing excess potassium and tartaric acid under chilled conditions as Potassium Bitartrate to prevent its precipitation in the bottle when chilled. CLICK HERE FOR TUTORIAL


An unpleasant bitter taint in a wine caused by an impurity of infection in the cork. Signified by a distinct damp cellar smell.


Corks come in variety shapes and materials. The most common are Natural , Compressed, Twin, and man-made material (Normacorks). It is basically up to the winemaker to decide which one to use.

Country wines

A term used to mean wines that are not made of grape juice.

Crown Caps

Known in the non-winemaking world as beer caps.


Destalks and crushes grapes.


A mead with apple juice added (and thus you might consider it either an apple melomel or a cider with honey.


Remove wine from the sediment in the bottle into a clean container for presentation.


A process that must be done to release the CO2 in solution of a wine. Oftentimes overlooked, but can be tasted if not thoroughly completed. See tutorial section for detailed help. CLICK HERE FOR TUTORIAL


A container identical in function and similar in shape to a carbuoy. They typically hold 25 to 54 litres, about 5 to 14 imp gal (6 to 17 USG) though come in various sizes as small as 1/2 imperial gallon.

Diammonium phosphate

A source of nitrogen for stuck ferments.


The process of removing the sediment from a bottle of sparkling wine before it is charged with the dosage.

Double-lever corker

Usually solid aluminium design. Grabs around the neck of the bottle. Plastic handles, can be adjustable or not. See tutorial section for more information on corking.


The bubbling of gas from wine or beer.


Vacuum bottle filler for bottling wine, beer, juices, etc, without needing to mmove the demijohn. Functions with vacuum pressure. Thanks to the vacuum, the wine is not affected by oxygen. Automatic filling head, high capacity and solid finish. It is possible to syphon and filter at the same time.


Any of numerous protein molecules produced by living organisms (including yeast) and functioning as catalysts in biochemical reactions. Despite their derivation from living materials, are not living organisms themselves. Enzymes emerge intact from the catalytic reactions they produce and are denatured (rendered inactive) by pH extremes and high temperatures. Usually, an enzyme acts only on a specific molecule (substrate), so an enzyme that acts upon pectin will not act upon starch. In winemaking, most of the essential enzymes are produced by yeast, but some are not and must be introduced by the winemaker. Some of the more important enzymes that find use in winemaking are: Amylase: An enzyme that catalyzes the hydrolysis of starch into maltose and dextrin. Cellulase: Any of several enzymes that catalyze the hydrolysis of cellulose. Invertase: An enzyme that catalyzes the hydrolysis of sucrose into an equal mixture of glucose and fructose. Lactase: An enzyme that catalyzes the hydrolysis of lactose into glucose and galactose. Lipase: Any of a group of enzymes that catalyze the hydrolysis of triglycerides into glycerol and fatty acids. Maltase: An enzyme that catalyzes the hydrolysis maltose to glucose. Pectinase: An enzyme that catalyzes the hydrolysis of pectin to pectic acid and methanol


A compound formed by a reaction between an acid and an alcohol, e.g. ethyl acetate.

Ethyl acetate

A fruity-smelling ester formed from ethyl alcohol and acetic acid, present in small quantities in most wines and beers, and produced by the yeast. When present in considerable extent, it is unpleasant and an indication of acetification.

Ethyl alcohol

The main product of anaerobic fermentation of a suitable sugar solution by Saccharomyces yeasts. The alcoholic base of wines, beers, liqueurs and spirits.

Ferment to dryness

Let the fermentation to continue to a specific gravity of 1.000 or lower. Then, the fermentation has been completed.


The production of all alcoholic beverages employs ethanol fermentation by yeast. Wines are produced by fermentation of the natural sugars present in fruits and grapes. Beers, ales, and whiskeys employ fermentation of grain starches that have been converted to sugar by the application of the enzyme, amylase, which is present in grain kernels that have been germinated.


Filtering a finished wine to remove finings and/or impurities. This can also help in stabilizing the wine. CLICK HERE FOR FILTERING WITH MINI-JET TUTORIAL


The use of some agent that will collect fine particles (cloudiness) in the wine and cause them to fall to the bottom so that clear wine can be racked off the top. For technical types, it's called clarification and flocculation. These substances are usually isinglass (ground fishbladders) or a gelatin substance, but also include bentonite and various cationic and anionic polymers.

Fizz Ex

Whizz-Stick. A drill attachment used to degas wines.

Floor corker

Corkers that can be stood on the floor. Can be used while sitting. The cork is first compressed cylindrically by the iris, and then pushed straight into the bottle. Come in Italian (metal iris) and Portuguese (plastic iris) styles.

Food Grade

Food grade plastic does not contain dyes or recycled plastic deemed harmful to humans. However, this does not mean that food grade plastic cannot contain recycled plastic. Another aspect of food grade plastic is matching the appropriate type of plastic to the food in question. Foods that are highly acidic or that contain alcohol or fats can leach plastic additives from the packaging or container into the food. As a result, you should only use plastic containers that are FDA approved for the particular type of food the plastic will come into contact with. Finally, it should be noted that a plastic container can no longer be considered food grade if it has been used to store non-food items like chemicals,


Adding alcohol to a wine to increase the alcohol content. Used to stop fermentation. Sherries, Madeira, and ports are examples of where this is done.


Also known as levulose. For diabetics. Sweetness compared to sucrose (100) = 130.


Used for clarification of wines. Mostly used in combination with kieselsol. Comes in both powdered and liquid forms.


The term given to the fault produced by the action of lactic acid bacteria on sorbic acid added to a wine as a stabiliser. Cannot be remedied, but can be avoided by adequate sulphiting the wine when sorbic acid is added.


A substance used to give body and some sweetness to a wine.


Ethanol fermentation breaks the pyruvate down into ethanol and carbon dioxide. It is important in bread-making, brewing, and wine-making. Usually only one of the products is desired; in bread-making, the alcohol is baked out, and, in alcohol production, the carbon dioxide is released into the atmosphere or used for carbonating the beverage. When the ferment has a high concentration of pectin, minute quantities of methanol can be produced.


Consumer of vast quantities of Port


Annual event held in Knottingley, where fresh winemaking grapes from Italy Sicily and Spain are processed (much drinking and frivolity) bring a tent

Gross Lees

Loose sediments containing a large quantity of fine pulp from the fruit or other base materials from which the wine is made. The pulp does not compact well on its own and therefore is loosely suspended in wine. Gross lees can be compacted somewhat by adding gelatin to the wine, or they can be coarsely filtered or centrifuged to recover much of the wine trapped within them.

Hand corker

Not to be used by hobbyists on any level. (they are pants)See double lever corker or floor corker.

Harris Filter

Gravity filter for the budget-minded, but careful-minded winemaker. This filter is ideal for small batches of wine (4.5 gallons). It is easy to connect to a siphon. One filter pad is needed per filtration.


Gravity and time and a good racking schedule will normally be enough to clear your wine, but occasionally the wine will not clear of it's own accord, this can be caused by many things, but the most common would be a "haze" caused by the presence of pectin, starch or tartrates in your wine. CLICK HERE FOR TUTORIAL


An instrument for measuring the specific gravity (abbreviated as s.g.), relative to sugar content, of a liquid. The importance of s.g. rests in its indication of proofing potential. In other words, s.g. indicates how much dissolved sugar is present for conversion to alcohol by yeast, what that proof will be, and how much sugar to add to raise the finished proof to a specific level. See tutorial thread for directions on usage and calibration


Iodine based cleaner for both wine and beer making. You must rinse with clear water afterwards. Do not use on copper, aluminum, silver or wood.


Used especially for clarification of wine, juices, etc. It is most commonly used with liquid gelatine, which results in a very fast action with little precipitation.


Non fermentable sugar, ideal for sweetening wines that are too dry. Sweetness compared to sucrose (100) = 30.


The solids that have fallen to the bottom of your fermentation vessel. Among much else, they contain live and dead yeast.

Log Sheet

Vital in winemaking. This is a log that records all of your winemaking procedures, so that you can reproduce your wine or correct the faults you made the last time. CLICK HERE FOR DOWNLOADABLE WINE LOG

Malic acid

Another acid present in fruits that is used to acidify wine.

Malolactic Fermentation (MLF)

MLF for short, this is a bacterial fermentation which can occur after yeast fermentation winds down or finishes. The bacterium Bacillus gracile converts malic acid into lactic acid and carbon dioxide. Lactic acid is much less harsh than malic and thereby softens and smooths the wine, but the wine also is endowed with a cleaner, fresher taste. In addition, diacetyl (or biacetyl) is produced as a byproduct, which resembles the smell of heated butter and adds complexity to wine. MLF is a positive event in some cases and has a downside in others--the fruitiness of wines undergoing MLF is diminished and sometimes off-odours can result. To ensure MLF, the wine should not be heavily sulphited and it should be inoculated with an MLF culture. If MLF occurs after bottling, it produces a slightly carbonated wine which may or may not be appreciated.


A fermented beverage made from honey, water, acid, yeast nutrients, and yeast. Tanninay also be addd, but the onlylavor is derivedfrom the honey itself. Different honeys, meaning honeys made from different nectar sources (flowers), yield different flavors. Thus, a clover mead is made with honey produced primarily from the nectar of clover flowers, while a heather mead is made with honey produced primarily from the nectar of heather flowers. There are three kinds of "true" mead: Dry Mead contain no flavoring other than honey and is made using about 2-1/2 pounds of honey per U.S. gallon of mead. Sack Mead contains no flavoring other than honey but is sweeter than most other meads and is made using about 4 pounds of honey per U.S. gallon of mead. Small Mead contains no flavoring other than honey but is made using only about 1-1/4 to 1-1/2 pounds of honey per U.S. gallon of mead and is fermented using an ale yeast. A small mead is closer to ale than to wine, while both dry and sack meads are closer to wine. Additionally, there are other beverages made with honey that are generally referred to as meads but indeed have their own names. Just a few of these (there are scores of them) are: Cyser is a sack mead (actually, a Melomel) made with honey and apples and is closely related to hard cider. Hippocras is a spiced pyment . Melomel is a mead made with honey and fruit. Another name for this type of mead is Mulsum. Metheglin is a sack mead made with honey and herbs and/or spices. Morat is a sack mead (actually, a Melomel) made with honey and mulberries. Mulsum is another name for Melomel. Perry is a sack mead (actually, a Melomel) made with honey and pears. Pyment is a mead (actually, a Melomel) made with honey and grapes or grape juice. Rhodamel is a mead (actually, a Metheglin)


A mead with fruit and/or fruit juices added.


A meniscus is a concave curve in the surface of a liquid and is produced in response to the surface of the container or another object.


Methanol, also known as methyl alcohol, carbinol, wood alcohol, wood naphtha or wood spirits, is a chemical compound with chemical formula CH3OH (often abbreviated MeOH). It is the simplest alcohol, and is a light, volatile, colourless, flammable, poisonous liquid with a distinctive odor that is somewhat milder and sweeter than ethanol (ethyl alcohol). At room temperature it is a polar liquid and is used as an antifreeze, solvent, fuel, and as a denaturant for ethyl alcohol. It is also used for producing biodiesel via transesterification reaction. DO NOT ATTEMPT TO MAKE THIS AT HOME!


A mead with herbs and/or spices added.


A filtering system ideal for small quantities (max 40 l each time). With its incorporated pump, this electrical filter will filter up to 20 liters of wine in only 15 minutes. Siltering surface: 465 cm2. Uses three filter plates.


A characteristic and unpleasant taint in wine or beer, usually detected in the after-taste rather than in the odour or on the palate. Caused by some Brettanomyces yeasts or lactic acid bacteria. Not detectable by everyone. The mousey smell of a suspect wine may be developed either by rubbing a drop briskly between the hands or by neutralising its acidity with the addition of sodium bicarbonate.


The juices, sugars, and water that become wine after fermentation


liquid used for removal of colloidal hazes, 1 year shelf life, often used with bentonite and gelatin as a tannin substitute


A synthetic cork that allows wine to breathe and age as with natural corks.


Search engine wizard


The smell of a wine or beer. Also used in the term 'to nose a wine.'

Oak chips

Used to give wines an oaky taste.


The chemical reaction between air and wine. A fault in wine.


Shitty tasting vegetable used to make crap wine (wormucus poous)


Large protein molecules that won't allow the wine to clear properly. They're important in jam making, but annoying and undesireable in winemaking. Released when hot water is used in musr preparation, removed from musts by adding Pectolase (pectin destroying enzyme) at the rate of 1 tsp per (UK) gallon, double this dose if hot water is used in any part of the preparation of the must.

Pectin haze

Pectins are complex polysaccharide molecules extracted from plant cell walls and capable of forming gels.


Pectic Enzyme. Pectic enzymes break up pectin to make smaller molecules that clear more easily.


Fizzy wine. The French word for a slightly sparkling wine.


A measurement of the degree of acidity or alkalinity of a liquid, represented by a number from 0 to 14. Decreasing values below 7 represent increasing degrees of acidity. pH influences the colour and taste of wines and beers, and the action of enzymes, fining agents, yeasts and bacteria.

Polyclar VT (PVPP)

Combines with phenolic compounds, add directly to wine, wine should be filtered after use.

Potassium Bitartrate

A salt of potassium and tartaric acid which can precipitate out of a wine as crystals under chilled conditions. Cold stabilisation

Primary Fermentation

The initial, main alcohol fermentation by yeast. It is usually begun by adding an active yeast starter to a must or juice in a covered primary fermentation vessel, but may begin spontaneously from wild yeast on the grapes or fresh fruit base. After a period of vigorous fermentation, the must is pressed or strained and/or the juice is transferred to a secondary fermentation vessel (e.g. a carbuoy or demijohn) and covered by an airlock. Even though the wine is now in a secondary fermentation vessel, the alcohol fermentation taking place is a continuation of the primary fermentation.

Primary Fermentation Vessel

A crock, bowl, bucket, pail, or other non-reactive, food-safe vessel in which the initial, or primary fermentation takes place. The primary should be capable of containing 1/4 to 1/2 more volume than the volume of the must it will contain to allow for a rising of the cap and a sufficient ullage above the cap to allow a good aerobic fermentation. Thus, a 1-1/2 gallon bucket is about right for a 1-gallon batch of wine, although a larger vessel is OK. Typically, the primary has a large mouth to allow easy access. It should be covered during fermentation to prevent dust and airborne bacteria, molds and wild yeast from settling into it, but should not initially be closed air-tight as it is desirous for the must to have exposure to plenty of air during the first 48-72 hours of fermentation. Also known as the primary.


The addition of sugar to a beer or wine after the main fermentation, in order to produce a further fermentation in bottle which produces the effervescence or condition.

Punching Down

The process of pushing the cap of skins, seeds and pulp down into the juice during fermentation. This facilitates extraction of color, flavor, and tannins and ensures that the cap doesn't dry out and develop unwanted mold or bacteria.


The curved bottom part of a wine bottle, used by judges to hold the bottle correctly.


Honey and grape juice fermented together. This can be either a fermented combination (as a melomel) or grape wine to which honey is added after it is finished.


Transferring wine by siphoning clear wine from one vessel into another closed vessel without transferring the lees at the bottom of the first vessel.

Racking tube

A food-grade tube that allows you to syphon wines from your fermentation vessels.

Residual Sugar

The amount of sugar, both fermentable and unfermentable, left in a wine after fermentation is complete or permanently halted by stabilization. Fermentation is complete when either all the fermentable sugar has been converted by the yeast into alcohol and carbon dioxide as byproducts or when the concentration of alcohol produced reaches a level that is toxic to the yeast and they die. Fermentation is permanently halted by stabilization through several means involving intervention by man.

Reverse Osmosis

A method of separating various dissolved substances, similar to what cells do, only backwards. High pressures force a liquid through a membrane with very fine pores. Typically we are interested in city water being forced through an RO filter to produce an ulra-pure water for the purpose of either reconstituting concentrated juice or as part of a fruit wine recipe so as to avoid off flavours or other undesired dissolved solids.


See description for goldseal....peas in a pod they are!


Two planks with a hinge holding them together end to end, holes along their length wide enough to hold the necks of champagne bottles, and a chain or rope on each side that are used to adjust the distance of the bases of the boards, and therefore the angle at which the boards are to horizontal.


A bacterial disease which turns wine or beer into a viscous, oily looking liquid and can generate jelly-like 'ropes' or clots. Infected wines may be sulphited and/or pasteurised. Affected beers should be poured away!

Screw caps

Yes, these can be used in winemaking. Sanitation is key here, and are also available retail. (Also known as Pilfer proof caps).

Secondary Fermentation

A second alcohol fermentation by yeast performed in a champagne bottle secured with a special, hollow closure secured with a wire "cage," the purpose of which is to trap the carbon dioxide produced by the fermentation and force it to be absorbed into the wine, or a bacterial fermentation called malolactic fermentation. The result is a Sparkling Wine. This secondary fermentation can actually be a continuation of the fermentation by the original yeast inoculation or can be induced at bottling time by inoculating a sweetened still wine with a second yeast especially adept at fermenting under pressure. It is NOT correct to refer to the alcohol fermentation in a secondary fermentation vessel (e.g. a carbuoy) as a secondary fermentation although novices to the hobby often do. However, a malolactic fermentation is correctly a secondary fermentation.

Secondary Fermentation Vessel

A jug, jar, bottle, demi-john, or carboy in which the second phase of fermentation takes place. This vessel typically has a wide body and tapered neck leading up to a small opening which can be sealed with an air lock. Also known as the secondary.


The grainy, bitter-tasting deposit sometimes found in bottles of older wines. Sediment is the natural separation of bitartrates, tannins, and color pigments that occurs as wines age and may indicate a wine of superior maturity. Also known as Crust, especially in port wines.


Unit of furniture/fixing, for storing stuff on.......made at least 400 times more effective by having a "cupboard" around it.


Potassium Sorbate, also known as "Sorbistat K" and affectionately as "wine stabilizer," potassium sorbate produces sorbic acid when added to wine. It serves two purposes. When active fermentation has ceased and the wine racked the final time after clearing, 1/2 tsp. added to 1 gallon of wine will render any surviving yeast incapable of multiplying. Yeast living at that moment can continue fermenting any residual sugar into CO2 and alcohol, but when they die no new yeast will be present to cause future fermentation. When a wine is sweetened before bottling potassium sorbate is used to prevent refermentation. It should always be used in conjunction with potassium metabisulfite or Sodium metabisulphite (1/4 teaspoon per 5 gallons of wine or 1 crushed and dissolved Campden tablet per gallon or 5ml of 10% sulphite solution) and the wine will not be stabilized without it. It is primarily used with sweet wines and sparkling wines, but may be added to table wines which exhibit difficulty in maintaining clarity after fining.

Sorbic acid

An organic acid used to stabilise sweet wines by preventing yeast multiplication. May be used as such or as potassium sorbate.


Attracts negatively charged particles which agglomerate and settle out, mix with hot water, add mixture to wine

Specific Gravity

A measure of the density or mass of a solution, such as must or wine, as a ratio to an equal volume of a standardized substance, such as distilled water. Before fermentation, the density of the must or juice is high because sugar is dissolved in it, making it thicker than plain water. As the sugar is converted by the yeast into alcohol and carbon dioxide, the density (specific gravity) drops. A hydrometer measures specific gravity (s.g. for short), with an s.g. of 1.000 being the calibrated density of distilled water at a specific temperature (usually 59 or 60 degrees F.). Because alcohol is actually less dense than water, the final s.g. of a wine can be less than 1.000, or lighter than water.

Splash Rack

Racking via syphon allowing air into the liquid by having the drop from syphon tube to receiving container to be at least 1 foot, therby allowing aeration of the must (normally avoided when racking)


Using a a chemical such as potassium sorbate or extra alcohol (fortification) to make a wine stable and to prevent further fermentation.

Starter kit

Usually, what you can buy in a winemaking supply store. Should include the following: Fermenting bucket, Demijohn, Airlock, Bung, Syphon tube, hydrometer, bottle brush, sanitation powder, corker, corks.

Straining bag

Sturdy bags made to ferment fruit in them. Can be made of terylene or muslin.

Stuck fermentation

A fermentation that has halted before all the sugar is transformed into alcohol. See tutoprials section for guidance.




One of two compounds which may be used to sanitize winemaking equipment and utensils (the other being sodium metabisulfite). Potassium metabisulfite is the active ingredient in Campden tablets. Its action, in water or wine, inhibits harmful bacteria through the release of sulfur dioxide, a powerful antiseptic. It can be used for sanitizing equipment and the must from which wine is to be made. A 10% solution can be made (100 grams made up to 1 liter with water). five milliliters of this 10% solution added to a U.K. gallon of must will add approximately 50 ppm of sulfur dioxide (SO2) to the must. One should wait at least 12 hours after sanitizing the must before adding the yeast. Sodium Metabisulfite: One of two compounds commonly used to sanitize winemaking equipment and utensils, the other being potassium metabisulfite. Its action, in water, inhibits harmful bacteria through the release of sulfur dioxide (SO2), a powerful antiseptic. It can be used for sanitizing equipment, but in the U.S.A the government prohibits its inclusion in commercial wine and thus it should not be used to sanitise the must from which wine is to be made. It is about 8% stronger than potassium metabisulfite.

Sulphur dioxide

SO2. The pungent gas, usually used in solution to sanitise wine and beer making equipment and bottles. Also added, particularly to dry white table wines, to retard oxidation.


a small, pale golden-green grape originating in Smyrna, Turkey. It is the most widely planted variety in California, where it goes by the name of Thompson Seedless. It is the common "white" or "golden" raisin sold in America.

Sur Lie Aging

French for "on the lees", this is the process of leaving the lees in the wine for a few months to a year, accompanied by a regime of periodic stirring. Certain wines such as chardonnay or sauvignon blanc benefit from autolysis because they gain complexity during the process that enhances their structure and mouthfeel, give them extra body, and increase their aromatic complexity. Aging sur lie with lees stirring can result in a creamy, viscous mouthfeel.

Sweet Reserve

Or Susse Reserve. A sample of the original juice from which a wine is made, used to sweeten the finished wine after fermenting to dryness and stabilized. The sweet reserve is either refrigerated or frozen until needed. When making a sweet reserve from whole fruit, such as strawberries, peaches, or plums, the fruit must be crushed and pressed and the juice stood in a tall, clear, glass bottle in a refrigerator until the juice separates (i.e. pulp sediment settles to the bottom of the bottle). The clear juice is very carefully racked off the sediment and stored for the reserve. The sediment can be lightly pressed through a double layer of sanitized muslin cloth and the liquid obtained allowed to separate out again, with the clear juice again removed and stored with the sweet reserve. The advantage of using a sweet reserve to sweeten a stabilized dry wine is the it adds sweetness, fresh flavor, and natural aroma to the wine. It may also improve the color of the finished wine somewhat.


A taste sensation most commonly associated in wines with sugars (glucose and fructose), glycerol, ethanol, and 2,3-butanediol (the latter in trace amounts). While the threshold for detecting sweetness (as sugars) is about 1% by weight, the threshold for classifying a wine as sweet is usually 2% by weight (specific gravity of 1.008) for a wine with 12% alcohol by volume. Sweetness does appear to soften some flavor components and blend with others to enhance their recognition. A wine with poor fruit flavor as a dry wine may possess more recognizable fruitiness when sweetened.


Using gravity and a racking tube to rack wine from one vessel to another.


An astringent. It usually refers to grape tannin, although it is also present in oak. Traditionally more present in red wines than in white.

Tartaric acid

An acid present in fruits, especially grapes.


Trichloroanisol. A chemical agent commonly found in bark cork. When wine is contaminated with TCA it will taste of wet, musty cardboard. and smell of damp cellar.


A method used in some tests for acid.


A device used in aiding in degassing of wines.


A term used to describe the variety of grapes a wine has been made out of.

Vitamin B12

Particularly important for the fermentation of grapes and fruits that have been partly infected by Botrytis.

Volatile acidity

Low levels of volatile organic acids, mainly acetic acid, are present in normal wines and beers. An appreciable increase in volatile acidity during storage, giving an unpleasant bouquet and flavour, indicates bacterial spoilage. See acidification.

Wild Yeast

Any mixture of the thousands of yeast strains which may be airborne or on the fruit, exclusive of the cultured wine yeast deliberately added to a must. Grapes, fruit and the air often contain spoilage bacteria, molds or yeast which can destroy a wine's quality, but if no spoilage yeast or bacteria are present in the must the fermentation can produce an acceptable wine. Due to the risk from spoilage organisms, prudent winemakers treat their must with an aseptic dose of sulfite to kill non-yeast organisms, stun wild yeasts into temporary inactivity, and thereby allow their own choice of cultured yeast to dominate the fermentation.

Wine Log

See log sheet

Wine Thief

A hollow tube similar to a turkey baster that has a hole on each end, one at the bottom to allow wine in when you put it into your wine, and the other at the top to cover with your thumb when you take it out so that the wine in the tube stays there until you put it over a glass and uncover the hole at top to release the wine. Also, someone who takes some of your wine without your knowledge; typically the culprit is a family member or friend. :)

Word Association

Innocent passtime for genius winemakers

Yeast nutrient

Extra vitamins and food to feed the yeast in wine musts. Not all nutrients contain Vitamin B1, so check the labels, Vit B1 is important for energising the yeasties

Yeast starter

A way of "preparing" the yeast before adding it to the must. CLICK HERE FOR TUTORIAL


see here for more detailed info and a list of yeast strains CLICK HERE

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