Ben Evert.com

Ever smelled rotten eggs when you racked your wine? We sure hope not, but if you have, your wine has been bitten by the dreaded hydrogen sulfide bug. No one wants to drink wine that smells like rotten eggs, so is there anything you can do to save the wine? You bet. Better yet, we’ll offer some tips that should help you avoid the problem in the first place.

Pee-Yew!
Hydrogen sulfide (H2S) usually forms at the end of fermentation, but most home winemakers won’t notice a smelly problem until the first racking. If you do smell rotten eggs, the quicker you can act, you’ll increase the chances of saving your wine. If you tarry too long before treating the wine, hydrogen sulfide will react with other carbon compounds in the wine to create mercaptans, and later into disulfides. These boogers are extremely difficult to remove from your wine once formed, so the faster you can detect and treat your wine for hydrogen sulfide, the better!

Read how to fix it.

Technorati Tags : Wine, Winemaking, Homebrew

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LET’S MAKE THIS PERFECTLY CLEAR
As wine ages, natural settling and clarification will occur to some degree, although it is inefficient and inconsistent. The public, however, is usually unwilling to accept cloudy wine or wine with crystals or other particles in it, so various methods are used for “cleaning-up” and finishing wine after fermentation, either before, during, or after aging. These processes also insure a level of stability or shelf-life for wines shipped to retail or restaurant outlets where the bottles may spend some time “on the shelf” before purchase and consumption.

Clarification methods are similar for both white and red wines. All methods of clarification remove unsightly particles from wine, but may also strip wine of pleasant aroma and flavor elements, body, and color.

Racking is the oldest technique of clarification that is just one step beyond natural settling. This is simply siphoning off the relatively clear wine after the lees have settled to the bottom, leaving them behind to discard. The lees are the insoluble matter including dirt and dust, cellulose, dead yeast cells, bacteria, tartrates and pectin. Racking may be done only once or several times before a wine is bottled. Red wines, especially those barrel-aged, are sometimes bottled after racking without further processing.

Cold stabilization may be considered an adjunct or enhancement to racking. This process removes excess tartaric acid that, if untreated, might later form potassium bitartrate crystals, which can show up in wine bottles or on corks. Although these tartrates dissolve easily and are edible (cream of tartar, commonly used in cooking) and harmless, they can alarm the uninformed consumer who thinks there is “broken glass” in his wine. Cold stabilization is accomplished by allowing the wine to warm up to “room temperature” and then chilling it down to about 40° F. The tartaric acid crystallizes in the tank and the wine drawn off by racking.

Fining is a method of clarifying or chemically stabilizing wine. The procedure begins by stirring into the container of wine a fining agent that is heavier than both water and alcohol and does not dissolve in either. The agent ultimately settles to the bottom of the vessel (tank or barrel), causing small suspended particles to precipitate out along with the agent. The clarified wine is then separated by siphoning (racking) off the settlings (lees).

Fining can lower high levels of tannin, remove haze, and reduce color. Care needs to be taken to chose the proper fining level that conforms the wine style that winemaker wants to achieve. Over-fining can result in thin wines that lack aroma complexity, flavor depth, viscosity, and aging potential.

Physical agents work by absorbing tiny particles and dragging them. Chemical agents work by forming chemical bonds with hydrogen elements in the undesired particles. Fining agents include egg white, milk, blood, gelatin, carbon, casein (the principal protein constituent of milk and cheese) and isinglass (an extract of sturgeon bladders). Heat stabilization is a fining process that uses bentonite (a clay of hydrated magnesium silicates) to remove protein, which may cloud a wine.

Filtering means passing the wine through a filter small enough to remove undesirable elements. Various filtering technologies allow great flexibility to winemakers to make stable wines of varying styles. As with fining, filtering can also remove elements that contribute to flavors and aromas, so winemakers need to be judicious and conservative with this technique to avoid “collateral damage” that leaves their wine clean but lifeless.

Depth or sheet filtration uses a relatively thick layer of fine material (diatomaceous earth, cellulose powder, perlite, etc.) to trap and remove small particles. Surface or membrane filtration passes wine through a thin film of plastic polymer with uniformly-sized holes that are smaller than the particles.

Sterile filtration uses micropore filters, which are fine enough to remove yeast cells, to prevent further fermentation. This is especially significant when residual sugar is allowed to remain in the wine at low levels. Prior to the advent of modern micropore filtration, slightly sweet wines were endangered by the possibility of revived fermentation in the bottle.

Semillon grapes make up 80% of the blend in the most expensive and famous dessert wine in the world, Château d’Yquem. Semillon seems the favorite foil of Botrytis Cinerea, the noble rot which concentrates the sugars and flavors and intensifies the aromas for d’Yquem and the other “late-harvest” dessert wines of Monbazillac and Sauternes. These wines hold up spectacularly in antiquity, unique in the spectrum of unfortified wines.

Consistently productive at six to eight tons per acre and of vigorous vines, semillon is easy to cultivate. It is fairly resistant to common vine diseases, with the notable exception of rot, which most often is hoped to be the noble type and not the destructive strain. This viticultural profile has led to widespread propagation and popularity of semillon vineyards.

While semillon is the majority white variety in Bordeaux, Graves, and Sauternes, more grows in Chile than anywhere else on earth. Early in the viticultural development of Australia, semillon (often incorrectly labeled as Riesling) dominated as the major white variety, although the vineyards are mostly Chardonnay and sauvignon blanc today.

The ripe semillon berry is a rich yellow color at maturity, although increasing sun exposure may turn it amber-pink. In warmer climates, there is always danger of sunburn and raisining. If processed as a dry or semidry table wine, the thin skins and tender, juicy pulp require speedy but gentle handling.

Viognier seemed literally an endangered variety only a few years ago, but seems to be recovering worldwide in both popularity and acreage. Less than 35 acres remained planted in all of France, its homeland, in the late 1960s. Its newest realm, California, has 2,001 acres as of 2002 (although a considerable portion is not yet mature enough to bear a commercial crop) and there are also relatively new plantings in Australia and Brazil, as well as other U.S. plantings in Colorado, New York, North Carolina, Oregon, Texas, Virginia, and Washington.

The major drawback of the viognier grape is that it is a very shy producer and somewhat difficult to grow. Although drought tolerant, it is easily infected with powdery mildew in damp conditions or humid climates. Like many other varietals, viognier must be harvested at its peak of maturity in order to display its unique aroma and flavor character. The grape’s tendency to develop high sugar but low acid can result in wines with neutral, merely vinous flavors and high alcohol. These cultivation problems and producer desires to capitalize on the grape’s somewhat rarity combine to make many Viognier wines relatively expensive.

Probably the main attraction of Viognier is its potentially powerful, rich, and complex aroma that often seems like overripe apricots mixed with orange blossoms or acacia. With as distinctive and sweet an aroma-flavor profile as Gewürztraminer, Viognier is nevertheless usually made in a dry style and seems to appeal more to the typical Chardonnay drinker. The distinctive Viognier perfume holds up even when blended with a large portion of other grapes. The fruit usually has very deep color, but is somewhat low in acidity. As California wineries experiment with Viognier-Chardonnays, Viognier-Chenin Blancs, and Viognier-Colombards, this may be the grape’s ultimate destiny, as a blender.

Because the prime appeal of Viognier is its fresh and striking aroma, it is a wine that should be consumed young in most instances. The exception is Château Grillet, where the grapes are harvested early and the wine kept in oak for several months prior to bottling; this wine has a reputation for aging up to two decades.

Source: Winepros.org       Cellarnotes.net

Technorati Tags : Sauvignon, Blanc, Semillion, Viognier, Wine, Grapes, Winemaking

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Pinot blanc is a genetic mutation or clone of pinot gris, which is in turn, a clone of pinot noir. The leaf structure, clusters and berries so resemble Chardonnay that there are many vineyards in Europe where plantings of the two grapes are intermingled. This may have led to some confusion and mis-naming of grapes as “pinot chardonnay” (chardonnay is decidedly not of the pinot family).

Pinot blanc berry skins have an unusually high tannin content and the wines are prone to browning.

Pinot blanc is allowed in both the Mâconnais and wine labeled “Bourgogne Blanc”, but plantings are nearly phased out of the Burgundy appellation. There are still many pinot blanc vineyards in Alsace, where the variety sometimes is called Klevner.

Plantings are extensive in Italy, where the grape is known as pinot bianco. Many vintners there make relatively neutral-tasting, crisp, high-acid versions intended for early consumption. Due to its low aroma and high acid, high production clones of pinot blanc are also used for blending with muscat in Spumante.

There are vineyards in both Germany and Austria, where pinot blanc may be called Weissburgunder and is even made into a trockenbeerenauslese version. There is also much pinot blanc planted in Eastern Europe.

A considerable amount of pinot blanc is planted in Uruguay and Argentina. Most of the 1,000 or so acres of pinot blanc in California are planted in Monterey County.

Aroma in pinot blanc is very light, non-distinct, nearly neutral. It is balanced with high acid and can be full-bodied. California winemakers frequently get fairly good results by applying the same techniques as they might to Chardonnay, barrel fermentation, lees stirring, full malolactic, etc.

Pinot gris (or pinot grigio, as it is known in Italy) probably is the best-known “white” variant-clone of Pinot Noir. Ripe pinot gris grapes may be described as having colors from bluish grey to light pinkish brown. Clusters with a variety of colors are not unusual.

The variety can attain a very high level of sweetness, but will begin to lose acid rapidly when near to fully ripe. Sometimes it is used to add richness and to lighten, when blended with Pinot Noir.

Some pinot gris is grown in Burgundy, where it may be called pinot beurot. Where planted in Germany, it is known as ruländer. It is of little commercial significance in either locale. Friuli, in Italy, produces the largest quantity, but only two appellations have Pinot Gris stars in the wine quality galaxy: Alsace, France, the traditional base of Pinot Gris appreciation and Oregon, the newest Pinot Gris area to come to light.

In Alsace, the pinot gris grape is called tokay d’Alsace (no relation to the Hungarian Tokay). The Alsatians value it as a full-bodied wine that can stand up to food without introducing any flavors of its own. In Italy, Pinot Grigio can be quite distinguished, coming from some producers, especially in the Friuli region, who devote attention to growing and vinifying. Unfortunately for its reputation, there are many other Italian Pinot Grigio makers that overcrop and harvest early to produce crisp, but vapid wines.

Pinot Gris / Pinot Grigio is usually delicately fragrant and mildly floral with lightly lemon-citrus flavors. Depending upon ripeness at harvest and vinification technique, Pinot Gris can be tangy and light, or quite rich, round and full bodied. Made in an appropriate style, it is one dry white wine that may even age well.

The Riesling is considered on of the ‘noble’ grape varieties for wine making.  It can produce wines of high acidity and elegance in very cool growing conditions.  Its wines usually show fresh fruit flavors and a zesty character.  Riesling has the ability to produce wines that run the gamut from bone dry to very sweet but are usually made in dry of semi-dry styles.  It has perfumey aromas with peach and honeysuckle notes and can develop a ‘petrol’ nose as it ages.

Riesling does best in cool climates and is very resistant to frost.  It is planted very widely in the northern European growing regions but is less popular in other areas of the world.

In the right circumstances, some of the finest sweet wines in the world can be made from Riesling that has been affected by Botrytis Cinerea.  This mold attacks the skin of the grape and concentrates the sugars in the grape by allowing the water to evaporate.  This is especially true in the Moselle and Rhine river valleys of Germany as well as the Alsace region of France.  These wines are at the same time:  wonderful, rare, expensive and long-lived.

Source: Winepros.org        Cellarnotes.net

Technorati Tags : Pinot, Blanc, Gris, Riesling, Wine, Grapes, Winemaking

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