Article

Aging Gracefully

Some truly remarkable changes occur when a wine is allowed to age. The more simple initial aromas eventually give way to a panoply of rounded, complex bouquets. Cabernet can take on the more tantalizing spicy, plummy flavors married to softened, succulent tannins. Riesling can eventually show those wonderful, perfumed tropical fruit aromas with a mineral, kerosene edge. Your wines must be capable of aging by their innate properties — they must have the “right stuff.” Generally, wines need high acidity and flavor compounds and, where red wines are concerned, high tannins in order to age well. Wines also high in potential alcohol (i.e., sugars) make good age-worthy examples. Beyond this, your wines need to be stored properly in order to allow them to age gracefully.

Your wines should be stored in a vibration-free, cool (around 13° C, or 55° F), dark cellar (much more on proper storage later). The analytical tools that explain the process of wine aging have existed for only about twenty years, hence, there is still much mystery involving certain varieties that have been demonstrated to age well. We must also be careful not to attribute scientific findings from a certain wine or grape variety to others. In fact, much more is known about how most wines deteriorate in the short term than how a few wines flourish and improve over the long term. So, in order to avoid any pitfalls in logic, I will in this article be speaking generally.

Aging Through the Ages

The appreciation of finely aged wine stems from biblical times, to Luke, and to the Romans and Greeks. The best dried grape wines were normally aged as the high sugar content in them preserved them. The famous Falernian was one of these wines, fermented after the grapes were allowed to partially dry in order to concentrate the sugars and flavor compounds. It was the most sought after wine in ancient Rome. It was commonly kept for fifteen to twenty years before being approached, but it could be aged well beyond that. This, and other wines, were effectively aged in clay amphorae, often sealed with wax or resin, stoppered with a cork (where available), and sealed at the opening with more wax or resin. This storage method was nearly as effective as today’s bottle and cork. After the collapse of the Roman Empire, the low-alcohol northern European wines that emerged could be drunk for only a few months. Some sweeter and more alcoholic Mediterranean wines could be enjoyed a little longer.

Not until the sixteenth century was any semblance of modern wine management in evidence. Vintners were beginning to understand that wines exhibiting high levels of acidity and flavor components aged well. They also realized that a barrel needed to stay filled completely to fight destructive oxidation. Large casks of top-quality German riesling were diligently preserved because these wines exhibited the correct balance of sweetness and acidity and were being kept in cool cellars, with constant topping up. Henry VIII of England imported wines from all over Europe, particularly Anjou, Gascony and Burgundy (120 varieties were known), but these came in barrels, not bottles. Many sixteenth-century wines did not keep well, and those that did had an alcohol content of up to 17%. The king spent a fortune keeping his court in wines — up to 300 barrels at year! (Henry VIII: The King and His Court by Alison Weir [New York: Ballantine Books, 2001], p. 70.) Not only was this volume needed for his lavish entertaining, but as these barrels were emptied, resulting oxidation very quickly deteriorated the wine, hence the need for so many barrels.

The seventeenth-century development of storing wine in corked bottles was the real breakthrough in the aging process. Glass bottles are impervious to air and corks offer a good seal that allows microscopic amounts of air to enter the bottle over many years helping the aging process, and subsequently led to the actual shaping of today’s cylindrical, stackable bottle. The use of corked bottles quickly led to the re-appreciation of drinking aged wine, as wine drinkers once did during the Roman Empire, when the use of the amphora allowed extended aging.

Wines Worthy of Time

In order for a wine to show marked improvement and complexity through aging, it must start out with the correct properties. Most wines do not have these properties and are made to be consumed quite early — within a few months or years. Any blush wines, gamay, bardolino, soave and any light-bodied white wines are examples of wines that are meant to be drunk young. However, there are many wine varieties such as cabernet sauvignon, syrah, nebbiolo (plus most pinot noir, sangiovese and merlot) and riesling, chenin blanc (plus most chardonnay) that can develop added nuances and complexities through extended aging. Ice wines are also candidates for extended aging because they contain high acidity and high sugar levels.

For the home winemaker, the choices have never been greater in selecting a wine kit you wish to make into a wine destined for extended aging. You need only consult your local merchant in order to get the proper kit or set of ingredients that fall in line with the wine you want to make and the age or maturity at which you would like to drink it optimally. (I’ll discuss the stylistic differences between youthful versus mature wine below. Also, please consult the Summer 2000 issue of Winemaker for our guide on over 1,200 kits.)

There are two general phases of wine aging. Maturation occurs between fermentation and bottling and generally lasts from six to twenty-four months or more but, as is the case for sparkling wine, can continue for years longer. Bulk-aging is a form of extended maturation. Other wines, such as full-bodied reds, may also have a maturation period of this length. During this phase, the wine might undergo the secondary malolactic fermentation, may be racked occasionally, stored in oak (or inert container) and may be fined and/or filtered. Reductive aging begins after the wine has been bottled. (Some of the pre-bottling activities mentioned above are — in contrast to reductive — oxidative.) Reductive aging (or any reductive wine tasks) takes place in the absence of oxygen. While the small air gap, or ullage, is allowed contact with the bottled wine, aging in bottle is still considered to be reductive, as opposed to oxidative. Truly oxidative tasks are racking, filtering and bottling where the wine is truly “aerated” by the nature of the task. Sulfite is usually employed when these tasks are performed to combat any excessive oxidation and to help ensure a healthy development of the wine.

Aging Characteristics

As a wine ages, many of its key characteristics change, from color to taste and aroma. Home winemakers need to understand these changes before they can manipulate them to make better wines.

  1. Appearance

    While some red wines start out nearly black in color and some white wines start out clear, or colorless, both eventually turn to brown. The timing of these color changes is dependent on grape variety, vintage characteristics (i.e., how ripe is the source fruit), and the nature of the wine kit (e.g., concentrate, partial concentrate, or pure juice), and how properly stored is the finished wine, hence there is no magic formula to foretell these changes.

    Many red wines take on a more intense color after fermentation. This is more evident in pure juice wines where maximum color pigmentation has been macerated (or steeped) from the grape skins that are usually included in the kit with the juice. Deep purple, bluish black tinges will shift to black cherry /ruby-red colors, then on to garnet/brick hues, and finally on to mahogany/amber-brown after many years. Most pinot noirs will start out around the ruby-red-to-garnet part of this spectrum, as pinot has less color pigmentation.

    As your bottled red wines age, you can expect the accumulation of sediment. This is due to the behavior of phenolics found in grape skins that are responsible for color, tannins and flavor. In the winemaking process and during bottle aging, these phenolic compounds respond to each other, to the presence of wine acids and the periodic contact with oxygen. These compounds link together to form larger molecules that eventually are too complex to remain dissolved in the wine and are “thrown off” as sediment. (Conversely, white wines have much less color and tannins than do reds, and, thus, do not accumulate much sediment, if any.) This process continues well after bottling.

    Little has been discovered to explain the shift in color of white wines as they age. What has been proposed is that the eventual “browning” of white wines is due to the oxidation of their phenolics (color pigmentation, mainly), the effects of metal ions, and the caramelization of residual sugars. White wines typically begin nearly colorless to light straw-yellow in youth and take on more lemony-golden hues as they age, and finally becoming burnished gold/amber-brown. Most homemade wines, except ice wine and similar sweet dessert wines, won’t have the aging capability to become amber/brown. Any wine can reach an unhealthy, premature brown if exposed to excessive storage temperatures over the long term. Properly made and stored white wines usually take decades to reach the healthy amber/brown colors, far beyond the life of homemade wines, sadly.

    The most predictable sediment thrown off in white wines, if any, is crystals of potassium bitartrate. (Red wines throw off these crystals too, but they are harder to see because of the presence of the other sediments.) In my experience, these crystals manifest sooner in drier wines than sweeter ones. Generally, white wines that have fermented in barrel seem to have a greater potential for aging than those whites that are not barrel-fermented, due to the added tannins from the barrel (or oak chips). The more aromatic white wines, such as riesling and gewürztraminer, are not subjected to either oak fermentation or maturation because this sort of treatment would mask the aromatics. Whites affected by noble rot harbor a greater potential for aging than non-botrytic whites. White wines made from botrytis-affected grapes have a much higher concentration of acids and sugars than the non-botrytic wines and can, as a result, tolerate extended aging.

  2. Taste and Aroma

    The decision to age your wines and for what period of time is not only reliant on the wine’s inherent ability to age but, more importantly, on your wine enjoyment preferences. Some home winemakers like their wines with little aging while others may wait months or years to approach the first bottle from a batch. So, it is best to determine which way (generally) you would like to enjoy most of your wines. Deciding this before committing to a purchase should assure the most satisfaction from your wines. (I will discuss this under “Which wines to age.”)

    When your bottled wine ages, wine sugars (glucose and fructose) and wine acids begin detaching from each other, their structures change, as do their particular flavors, and this changes the profile of the wine. The wine ordinarily softens in flavor due to the formation of esters (reactions of organic acids and alcohols) and the reduction of acids through precipitation. Certain esters are formed during fermentation and others are formed during aging. The flavor compounds from the aromas of the grape (or concentrate or juice) and those from fermentation respond to each other and with other phenolics to gradually create a new, enhanced “bouquet” — a much nuanced, complex assortment of flavors and aromas.

    In red wines, bitter and astringent flavors and sensations change with aging. The polymerization of tannins with anthocyanins (compounds found in vine sap and grape skins responsible for color) helps to soften flavor and “mouth-feel” by reducing bitterness and astringency. Tannins can also bond to protein(s), precipitate, and help to soften your aging wine.

    The predictability of these chemical reactions and changes is uncertain at best, making it difficult to determine when a given wine has reached full maturity — the optimal point in the wine’s drink-ability, where the best possible balance has been reached between the softened tannins and complex flavors and aromas. This uncertainty is not necessarily a bad thing. With each subsequent bottle you open from a given batch, new discoveries can be made and enjoyed.

    Aging (white) wines “sur lies” is an old winemaking technique. Normally carried out with more neutral white wines (i.e., those with a more simple flavor and aroma profile), the technique involves extended aging of your wine on the dead yeast cells at the bottom of the fermentation vessel. This period may take a few extra weeks or more but is better determined by the variety (i.e., by how simple or complex it is), vintage characteristics, and the strain of yeast being used — best to ask your merchant for more details. The yeast cells impart more body to the wine and a slightly yeasty, or bready, character. In order to keep the wine on the yeast cells, the wine is necessarily racked fewer times than other white wine. The small amount of trapped and dissolved carbon dioxide (CO2) in the bottle wine helps to preserve the contents and then gives off a slight prickle and vigour when eventually poured. Muscadet is frequently aged “sur lies,” yet the practice has proven useful in adding flavor to many neutral white varieties.

Four Factors Affecting Aging

There are four factors that affect aging — temperature, oxygen, light, vibration. Each of these factors can be controlled by home winemakers to influcnce the way the wine ages.

  1. Temperature

    Temperature plays a paramount role both in the age-ability of your wine early on during fermentation and the aging of your bottled wines.

    Fermentation Temperatures

    Fermentation temperatures dictate the types of esters that are generated, which, in turn, directly have an impact on the age-ability of the wine. The more favorable esters are formed when optimum fermentation temperatures are adhered to. Better varietal character will also emerge in your wine if you follow optimum fermentation temperatures. Therefore, controlling the temperature of fermenting wine is very important. Below 10° C (50° F) most yeasts will be too slow — or worse, completely inactive — and may give way to a stuck fermentation . Above 45° C (113° F), yeasts are too damaged (or are quite probably dead) to ferment your wine cleanly. While this temperature seems excessive, these conditions can occur. Your wine must can easily be ruined in just a few hours, or less, if left in this environment. In the upper temperature ranges, where the yeasts are still working (i.e., high 27° C (80° F) to mid-32° C (90° F), or higher ) some chemical reactions are sped up and can bring on unwanted flavor compounds. Also, at higher temperatures, some of the good flavor compounds can be lost, carried away by excessive CO2. The wine can easily end up low in fruitiness and can smell and taste overly baked. If the fermentation temperature is allowed to rise to a point where yeasts are killed, the yeast cells exude compounds that prevent any subsequent yeast from working, even after cooling down of the must.

    White wines are typically fermented at cooler temperatures (between 12° C and 17° C, or between 54° F and 63° F) than red wines. This lower fermentation temperature preserves the primary grape aromatics. With white wine fermentation, there is no maceration of the grape skins with the must, as is the case with red wines (a warmer red wine fermentation assists this maceration). The more aromatic white varieties (e.g., sauvignon blanc, muscat, riesling, gewürztraminer) require fermentation temperatures at the lower end of the range to preserve their perfumed aromatics that might otherwise be lost at higher fermentation temperatures. Less aromatic whites (e.g., chardonnay, verdicchio, muscadet) can benefit from fermentation temperatures nearer to the upper end of the range because they may then take on secondary fermentation aromas from barrel fermentation, such as vanilla, oak and buttery characteristics (popular with chardonnay), and lees contact, which offers a yeasty, bready character (popular with muscadet).

    Fermenting your red wines at the correct temperature (between 25° C and 30° C, or between 77° F and 86° F) is critical to the extraction of ample tannins, anthocyanins and flavor compounds from the grape skins (this point is only relevant to home winemakers using pure juice that contain crushed grapes). Fermenting above 30° C may unduly slow or retard yeast activity, and, conversely, fermenting below 25° C may impede the proper extraction. Malolactic fermentation is best triggered with the inoculation of a malolactic culture (for more detail, refer to the article on malolactic fermentation in this issue). Generally, malolactic fermentation converts some of the harsher malic acids into the softer lactic acids, which results in a softer wine that is ready to drink sooner. The malolactic is also suitable for whites, like chardonnay, that may show a high, evident level of malic acid.

    Storage Temperature

    If all Winemaker readers had a wine storage area that stayed at a constant 13° C (around 55° F) with moderate humidity, that would be all the advice I would need to give regarding the proper temperature in which to age your bottled wines. What is of greater importance is controlling the temperature of the best space you have. While a 13° C wine cellar is ideal but unrealistic for most of us, great success can also be had with a cellar that stays constantly just below a comfortable room temperature (say, between 20° C and 22° C, or between 68° F and 72° F). Even slight variations from this range will not harm your wines.

    What you want to avoid is an environment where there is frequent, rapid and great changes in temperature; this is the wine-killer! In this sort of environment your wines would undergo great strain. Changes in temperature can produce changes in pressure and fluctuations in wine volume. This can compromise the seal created by the cork and the neck of the bottle and can eventually purge the seal, allowing oxygen to seep in and thereby adversely accelerate the aging process.

    Extremes in temperature at either end of the scale can severely and unduly influence the aging process. Heat both accelerates and (possibly) prematurely triggers the chemical reactions involved in otherwise healthy wine aging. Extended exposure to high temperatures will quickly deteriorate quality, in most wines, turning them prematurely brown and imparting unwanted “baked” flavors. Storing your wines at below 10° C (50° F) will conversely slow the chemical reactions responsible for reductive aging and will help maintain much of the primary (fresh, fruity) aromas. Finally, at really low temperatures (at freezing and below), the wines will expand enormously enough as it freezes and will force the cork from the bottle.

  2. Oxygen

    Although cork-stoppered wines intentionally allow for miniscule amounts of oxygen to seep in over a long period of time, amounts beyond this can prevent the proper development of bottle bouquet, and proper varietal aromas can also be obscured or destroyed.

    Some wines are more affected by oxygen than others (i.e., wines that are low in acidity, body, tannins, etc. — those traits that allow a wine to age extensively). A key factor influencing the potential oxidation of a given wine is its pH level. As pH rises (i.e., or as acidity falls), the potential for a wine’s oxidation increases. When pH rises the wine’s phenols are in a state that fosters their reacting to each other and falling out as sediment and increasing the wine’s potential for oxidation. Therefore, wines with a higher pH have lower potential for aging than wines with a lower pH.

  3. Light

    While exposure to sunlight has not been proven to directly adversely affect the aging process, it can provide the heat that can negatively accelerate the aging process. The ultraviolet range of the light spectrum can trigger oxidation. Light may also aid in the production of copper casse (this produces an orange-brown color as well as a musty smell). Therefore, try to age your wines in tinted glass containers, the darker the glass the better. The color of the bottle is really only secondary to the ambient light of your storage area.

    (“Please shut the light on your way out,” is the most obvious advice.)

  4. Vibration

    Storing wines in a cellar free of vibration seems to be based more on a romantic ideal than on any empirical evidence. There is no clear indication that vibration has any ill effect on the aging process. Vibration may impede the natural clarification process and the usual sedimentation of phenolic substances. My view, however, is “Why take the chance?” After all, if your optimal storage area is vibration-free, all the better. On the other hand, you shouldn’t worry needlessly if the 5:19 train gives a slight tremble to your wine room as it rumbles by.

    On the subject of transporting bottled wine, it is always a good idea to allow the wine to “recover” before opening it. The longer the trip, the longer the recovery period. This is the primary reason why a wine-kit recipe will suggest that you sample the first bottle at least one month after bottling. This is the period of time a newly bottled wine needs to recover from “bottle shock.” Transporting bottles in an upright position is less harmful because the air gap, or ullage, will barely stir up the wine. Transporting bottles in a horizontal position will allow the air bubble to travel the length of the bottle and cause the wine to stir considerably.

Which Wines to Age

There are a number of aspects to consider when determining which are the best wines to age, the most important of which are grape variety or wine style, vintage characteristics, and the nature of the wine kit (i.e., concentrate, partial concentrate or pure-juice kit).

As mentioned in the opening paragraph, a wine’s age-ability is directly related to its natural properties. A wine high in acids, tannins and phenols will stand up to extended aging better than a wine that is low in these components. High acidity is the most critical component. Acids in wine act as a preservative, much the same way as brine does in a pickle jar, plus wine acids provide something for the other harsh components, like tannin, to bind to and fall out (i.e., separate) from the aging wine. Acidity is the one property shared by age-worthy reds and whites. While white wines are comparatively low in tannins and the phenols responsible for color, there are still many white wine varieties and styles that can age extensively.

Speaking very generally, reds are more age-worthy than whites because they contain much higher levels of the tannins and phenols that are also responsible for preserving wines. However, there are a number of sturdy whites that can out-age the more feeble red varieties. Cabernet sauvignon, syrah, nebbiolo, sangiovese and tempranillo are red varietals that age well. Grenache, most merlot and pinot noir, zinfandel and any “blush” style wines do not generally age well extensively. (These varieties could age well extensively if they had high levels of acidity, tannins, phenols, etc. from a ripe vintage — this is where your background research and questions about the kit you buy pay off.) Riesling, chenin blanc, some pinot gris, and ice wines have the make-up to age extensively, while frascati, sauvignon blanc and muscat do not. These examples are mere guidelines that force the home winemaker to examine other relevant issues in the age-ability of a given wine.

Ascertaining vintage characteristics and what this will bring to bear on wine quality and age-ability is also important. Is your wine kit from one region or area? Is it a blend of more than one vintage (year)? What were the conditions of the growing season? What is the breakdown of the blend (of grape varieties)? These are important questions you should have your merchant answer in order to best understand the outcome of the finished wine and, hence, its age-ability. Understanding these factors, plus everything else I have mentioned, will best guide you to manage the wine you are making and outcome you are expecting. For example, if you are buying the most expensive Chianti kit your merchant offers, it really should be real sangiovese grown in the Chianti zone in Tuscany, as bona fide as the commercial finished equivalent. After all, this is what you are paying for. In short, gather as much information as possible about any wine kit you are considering buying. Competition is on your side; there are enough quality wine kits for you to choose and buy confidently.

Finally, you will have to consider the relative virtues of the various wine kit styles. Do you buy the four-week concentrate kit, or do you buy the longer-term pure-juice kit (or something in the middle)? I had always been of the opinion that the closer you get to using freshly harvested grapes, the better the results of the finished wine. In the concentration process, many vital constituents can be stripped away. In addition, you cannot control the maceration process with a concentrate kit as you can with a pure-juice kit that contains grape pulp. Yet, my supposition that pure-juice wine kits retain more of the natural constituents that lead them to a greater age-ability has been readjusted by improved technology and chemistry.

While wines made from pure-juice kits may eventually show some added nuances and proffer a more complete mouth-feel, today’s concentrates are formulated so that any of the essential trace elements lost in the concentration process are replaced. What this means is that now many shorter-term concentrate kits can be made over a longer period and can be matured much more extensively than before, and the finished wines will benefit from extended bottle-aging, much like their pure-juice equivalents.

For wine makers using fresh grapes, you may want to ask about the level of ripeness of the grapes when picked (usually expressed as a percentage of sugar, by weight, in the grapes), acidity levels, severity of pruning (usually the more severe, the riper the produce), and the age of the vines (the older the vines, the more complex the aroma profile of the fruit and the riper the grapes).

A wine kit that employs oak chips will make a wine that is a good candidate for extended aging. Whether the oak is used during the fermentation or the maturation process, tannins will be leached from the oak chips and will assist in the aging process.

Since there are so many unknown variables regarding a wine-kit purchase and the age-ability of the resulting wine, I do not want to draw any erroneous conclusions. For any example I cite, you could probably find an exception to disprove it. Gather the best, most useful information at the point of purchase. The more questions you ask, the more confident you will be with your plans for your wines.

Equipment and Process Considerations

  1. Carboys and Airlocks

    You may wish to bulk-age your wines (beyond the scope of a recipe) in carboys. Use only glass carboys for this. Plastic carboys are too porous for any extended aging. Air can seep in much more readily because the seal created by the rubber stopper and the carboy neck is not as reliable as the seal created with a glass carboy. The other danger with plastic is that there is a much greater risk of contamination by active micro-bacteria lurking in the porous interior from a previous batch.

    If you are bulk-aging with your glass carboy, you must manage the aging process carefully. You are, as the saying goes, “putting all your eggs in one basket.” If something goes really wrong, the whole batch could be irrevocably ruined. If you bottle a batch on schedule (sans bulk-aging), you then spread out any potential risk (such as any bottle variation within the same batch). Rack the wine gently every six to eight weeks (check the recipe for racking intervals). Sanitize any equipment thoroughly with sulfite. Sulfite will not only sterilize the racking equipment and the receiving carboy but will also help to counteract the effect of the wine’s contact with air and any lingering microbes. Bulk-aging would be appropriate if you are doing a “sur lies” treatment to your wine, for example. Some wine makers I have spoken to swear by bulk-aging as it allows a better melding of the post-fining/filtering aromatic constituents. The wine can be approached sooner in bottle, with the added benefit that it does not show the usual youthful, “candied” flavor profile (read, “bottle-stink”), and can still remain highly age-worthy.

    You may decide to seal the carboy with a solid rubber bung, replacing the bung and airlock. This eliminates the need to manage the airlock. If you’re keeping the airlock on, make sure it is well topped up; you do not want the water in it to evaporate. If you go away for any extended periods, fill the airlock with glycerine, as this will not evaporate. If you are using the solid bung, you must ensure that there is no residual fermentation happening in the carboy. If there is even imperceptible fermentation still going on, the seal will be purged and oxygen will have a chance to seep in.

  2. Bottles and Ullage

    The bottles you choose for a wine can have a marked effect on age-ability — so can the fill-level of your bottles, or ullage.

    Empirical studies have demonstrated that magnums (1.5 liters, or 52-ounce bottles) are ideal for your longest-aged wines, and, conversely, “halves” (375 milliliters, or 13-ounce bottles) should be opened before any other format. This is a direct function of ullage. If ullage, or air-space, is the same in the two formats, the ratio of air to wine will be greater in the half-sized bottles, thus accelerating the aging process. Of course, the reverse is true for the magnum bottle. There is great flexibility when filling your bottles and the way the ullage acts on your wine.

    Using dark-tinted bottles is also a good idea. It isn’t the light getting at the wine that one should be concerned about, as much as the heat generated by the light and the accelerated aging this heat can bring. So, the darker the bottle, the less are the deleterious effects of light and heat.

  3. Corks and Caps

    If you have bulk-aged your wines and if you also expect to extensively bottle-age your wines, take no chances and use the best-quality, longest corks possible. Most, if not all, merchants will carry natural, fifty-millimeter corks. I would stay away from any short corks (which are fine for shorter-term wines, say, one to three years, maximum, with small ullage) and avoid any agglomerated corks for your long-term wines. (Agglomerated corks are those made from cork particles re-pressed into a cork shape. These corks are more apt to crumble before you intend to uncork the wine.)

    Plastic screw-on caps provide as good a seal as you will need and the wine needn’t be stored on its side, as with cork-stoppered bottles. Remember, with cork-stoppered bottles, one must keep the bottles on their sides in order to keep the cork moist and expanded against the inside of the bottle neck to form the optimum seal. You must be very careful when sanitizing plastic caps, however, as they are particularly tricky to rinse due to their design. Sanitizing solution can remain trapped between the cap and the inside liner and this could ruin the bottled wine. Sterilize plastic caps by boiling them and avoid any of the conventional sterilizing agents, especially any bleach-type agents.

    The new plastic corks, or artificial corks, have been on the market for too short a time for any empirical conclusions to be drawn about their effectiveness in extended aging. Even commercially made wines have employed them too recently to fully understand how they perform.

  4. Fining and Filtering

    Aging can be accelerated by removing the solids of a young wine. The more solids removed, the shorter the successful aging period of your wine, generally, because the solids help to bring out the elevated aromas and flavors of your aged wine. Some of the suspended solids and heavier constituents will be removed during the fining and filtering process. Follow the recipe directions and I would recommend that, when you filter, use a manually powered filter unit, since you can control the pressure and the speed at which the wine is pressed through the filter pads. Motorized machines tend to filter quickly and can strip away more than needs to be removed, taking the “stuffing” out of the wine. Other winemakers may disagree. You may find a comfortable middle-ground by using a motorized filtration unit that offers multiple speeds, allowing you to filter your wines slowly or quickly. The advantage of the motorized unit is that the flow of the wine is steady. Remember that any wine kit that requires fining and/or filtering (which is just about every wine kit on the market) has been formulated to endure it and the wine will eventually blossom, showing its every charm. All that is needed is a little patience.