So you want to join our community!

If you already have an account, all you have to do is

Use and continue

New World Wine Maker Blog - general

The Winemaker as Artist

I have often written that there are only two processes in winemaking:    Flavours are created in the vineyard and extracted during winemaking.    I should probably add a third.   Flavours are modified by fining.    Apart from the removal of gas bubbles from molten glass, no one but a wine or beer maker seems to use the term fining.    If I were a visual artist, I would compare fining to the touches given to a painting to emphasize or suppress an image; the strength of highlights or depth of shadows.   

A winemaker is a sensory artist.    His pigment is a drawn from the vineyard and his brush a stainless steel tank or oak barrel.   There are no two identical wines.    Each wine is unique if you search out the details.    The winemaker’s mental image shapes the sensory properties, and lab analyses give reassurance of the pathway to create the wine conceived in the mind.  

The fundamental structure of a wine is determined by the chosen variety, the climate and soil in which it is grown, vineyard management, and stage of maturity at which it is harvested.   The winemaker must then decide on the strategy to be used to extract flavours.    There are so many ways to extract a grape that this stage alone is sufficient to account for the variation between wines of the same variety from different wineries.     This is not to minimize the influence of other factors, but winemakers often develop an extraction style using favoured techniques.    Those who become familiar with a particular winemaker’s style can often recognize wines from that winery, even though they may be from a different grape variety.    No other memory is as persistent as that of smell.

In a perfect world, there would be little else required of the winemaker except to extract, ferment, stabilize the wine, and clarify it for bottling.    But nothing is that perfect.    Sometimes a wine doesn’t settle easily or there may be an off note on the palate.    Now is the time for a fining agent.

The most fundamental fining agents are those which are insoluble, but have a property which enables them to remove an undesired component from a wine.   The best known of these is bentonite clay which is used to remove undesired protein from white wines.    Soluble protein can return to undermine the winemaker’s vision of a near perfect white wine by creating a haze months or years after it has been bottled.    A grape-derived alternative to bentonite is tannin.    Most red wines have enough tannin that they require no bentonite.   Tannin and bentonite each have an opposite molecular charge to protein, thus soluble protein will be neutralized by tannin or bentonite and will precipitate.   Higher levels of tannin remain in the wine and contribute to mouth feel and astringency, but excess bentonite can be a serious problem because it can create a non filterable haze.

During the past few years we have learned a great deal about many traditional practices of winemaking  and have put a new spin on them.    Winemakers have used a process called bâttonage for centuries but in recent years an objective examination of the process revealed unrecognized benefits associated with the practice.   In addition to imparting savoury sensory notes, the practice increases body and imparts antioxidant properties to the wine.    It consists of allowing the wine to remain in contact with the lees for an extended time.   The lees are regularly stirred in order to resuspend them in the wine and assist the dead yeast cells to break down and release their contents.   In recent years, wine ingredient suppliers have recognized the risk of developing off flavours that accompanies bâttonage and have made autolyzed yeast available as a wine treatment.   It’s become a simpler, more consistent part of the winemaker’s palette (not to be confused with palate, pallet, or pellet). 

The use of a fining agent that also imparts sensory properties moves the concept of fining agent into the realm of wine ingredient.   There are a number of commonly used winemaking practices that are gradually moving through this transition.   A common example is the use of oak barrel alternatives such as toasted oak chips or oak extracts.    This controversial alternative treatment can develop the nose, flavour, and palate of wine at much lower cost than the extraction of oak components from an expensive barrel.   When the oak alternatives are coupled with the exact oxidation of a micro-oxidation system, the process becomes not only less expensive but more exactly controlled for flavour development than the barrel alternative.    Barrel to barrel variation is eliminated, but the process can go terribly wrong in inexperienced hands if the wine is inadvertently over oxidized.   The highlights and shadows can be masked by the bitter and nutty notes of oxidation.

Modern winemaking is a highly competitive business with quality moving steadily upward.   The most important role of the winemaker is to provide the vision of the best he can extract from the vineyard and to know that if the best is not good enough for the market, then how he must upgrade it.

Gary Strachan is an expert consultant and planner for the grape and wine industry since 1977

Read article

Wine Phenols – White Varietal Processing Considerations

WHite crsuh grape

White varietal processing is largely aimed at minimizing phenolic extraction (except with the use of oak addtivies). This starts with harvesting. Machine harvesting grapes leads to greater berry breakage and increased skin/seed/stem contact compared to hand picking. Hand-picked grapes will usually undergo whole cluster pressing because maintaining the berry structure for as long as possible will help keep soluble solids to a minimum. With machine harvested fruit, pressing grapes as soon as possible will help limit phenolic extraction by decreasing skin contact.

Short-term skin contact (up to 12 hours) is particularly common with aromatic varietals such as Gewurztraminer, Albarino, and Sauvignon Blanc; this is typically desired for increased extraction of aromatic compounds and aromatic precursors rather than phenols. During these processes, phenolic extraction is kept to a minimum through the use of carbon dioxide and sulfur dioxide (limit oxidation) and during solids separation procedures.

Separation of free-run and press-fraction juice is commonly practiced in wineries (this will be discussed in more depth in a separate post). In regards to phenolics, press-fraction juice will have higher concentrations of flavonoid phenols due to higher soluble solids and increased contact with stems and seeds, and higher concentrations of hydrolyzable tannins due to oxidation.

Additives during pressing and solids separation are commonly used to decrease phenolic extraction. Sulfur dioxide is commonly added to machine harvested grapes pre-pressing to limit oxidation. Various commercially-produced enzymes, primarily pectinase, aid with the removal of soluble solids during solids separation activities (enzymes and solids separation will be discussed in depth in a following post). Bentonite, PVPP, and gelatine are all applicable for fining pre-fermentation and post-fermentation. Bentonite does not directly react with phenols but does help precipitate protein-phenol complexes; it is often used in conjunction with enzymes during cold settling to decrease soluble solids and create more compact lees. PVPP (polyvinylpolypyrolidone) is used specifically for removal of flavonoid phenols, while gelatine is more effective for removal of nonflavonoids. All fining agents can have a negative effect on aromatic compounds, so they are often considered a double-edged sword and application must be done carefully.

Hyperoxidation can also be used to remove phenols in white grape juice. This technique is primarily used on press-fraction juice and requires minimal sulfite levels. The juice is saturated with oxygen, leading to oxidation and sedimentation of phenolic compounds. Just like using fining agents, this technique will often lead to significant losses of aromatic compounds.

Oak may also be used during fermentation and maturation with various white varietals, most notably Chardonnay (oak and oak additives will be discussed in a following post).

Phenolic extraction with white varietals is desired by an increasing number of winemakers in order to produce desired wine styles with more body and mouthfeel.

The increasing popularity of ‘Orange wine’ in the modern market is just one example (no, this is nothing new; on-skins fermented whites have been produced for thousands of years). Some winemakers are beginning to think differently, using on-skin ferments and high-solids ferments to produce blending components. These wines often lack desired aromatics and flavours but have structure; integrated into blends, they produce wines of character that have the best of both worlds.

See previous posts on Wine Phenols: Flavonoids & Nonflavonoids

 

Mike Horton, the surfer with a passion for winemaking. The original blog Wine Phenols : Nonflavonoids and Flavonoids was originally posted on his blog: the drifting winemaker.

Read article

Bacteria in winemaking – it’s all about timing

Cheese

“The early bird gets the worm, but the second mouse gets the cheese.”
Willie Nelson

Being early is not always a guarantee of success, especially if you’re a mouse. Evidently, timing is critical. An example of this is gossiping about a colleague when he or she walks in (I never do this) or adding lysozyme to your must before co-inoculating with yeast and bacteria. As far as the latter example of bad timing is concerned, I know of a winemaker that did this. Suffice it to say, no MLF took place.

Timing is usually critically important in any winery, especially when it comes to the tiny microbes in your fermenting must and wine. The presence or absence of yeast and bacteria at certain stages of the winemaking process will ultimately determine the quality of your wine. For instance, a beer brewer phoned me a while ago and complained about bacterial spoilage of his artisan beers by lactic acid bacteria. I recommended Delvozyme® (a lysozyme preparation that Anchor sells locally) and have not heard from him since. No news is good news, right?

Another case comes to mind. A winemaker told me that he’s been involved in a long-standing feud with ubiquitous LAB that perennially invade his barrels of premium Chardonnay. The winemaker has since made a compromise, as a certain percentage of barrels are allowed to be annexed by the marauding LAB and the remainder of the barrels are treated with lysozyme. All the wine is eventually blended and the combination of wine with diacetyl notes versus more fruit driven wine has proven to be quite enchanting.

As a parting shot, I read about an Australian winemaker that was told by a consultant that he could use less sulphur in his wine if he used lysozyme during stabilisation. The end result; an oxidised, microbiologically stable wine and a well-timed kick to the consultant’s backside!

Bernard Mocke is a technical consultant for Oenobrands

Read article

If Only the Grapes Were the Whole Story

imagesCA6DV9JN

Wine has been described as the perfect beverage because the grapes contain all the ingredients necessary to create their transformation. Put grapes in a vat, and over time the yeasts coating the skins set alchemy in motion, converting the sugar in the juice into alcohol.

It was just this sort of unbidden fermentation that inspired humans so long ago to spend the next few millenniums improving their methods of winemaking.

A few wines are still made in this way, or at least in approximation, with no other ingredients except the possible addition of sulfur dioxide, which has been used for eons as a stabilizer and preservative. Yet it’s no secret that many wines (most, in fact) include a lot more than grapes, yeast and sulfur. The list in some cases can be staggering.

Forget about the often poisonous chemicals used in the vineyards, which can leave residue on the grapes. In the winery alone, before fermentation even begins, enzymes may be added to speed up the removal of solid particles from the juice, to amplify desirable aromas while eliminating disagreeable ones, to intensify the color of red wines and to clarify the color of whites.

It doesn’t stop there. Other additives can be used to enhance a wine’s texture, to add or subtract tannins or simply to adjust quality. Winemakers can select specific yeasts and special nutrients to keep those yeasts working. They can add oak extracts for flavor and further tannin adjustment, and compounds derived from grape juice to fix color, texture and body. They can add sugar to lengthen the fermentation, increasing the alcohol content; add acid if it’s lacking; add water if the alcohol level is too high. Or they can send the wine through a reverse-osmosis machine or other heavy equipment to diminish the alcohol and eliminate other undesirable traits, like volatile acidity.

For all of its natural, pastoral connotations, wine can very much be a manufactured product, processed to achieve a preconceived notion of how it should feel, smell and taste, and then rolled off the assembly line, year after year, as consistent and denatured as a potato chip or fast-food burger.

Yet we pay little attention to wine’s added ingredients, even as we have become hyper-conscious about what we eat. Twenty years ago, many Americans may have enjoyed food indiscriminately, but now they weigh the nutritional, environmental, humanitarian, aesthetic and even political consequences of what they cook and consume. Isn’t it time to devote the same careful attention to the wine we drink?

It’s no simple task. Unlike processed foods, wine is not required to have its ingredients listed on the label. This contributes to the belief that any wine is elemental, like fruits, vegetables and meats, and can’t be broken down into constituent parts. That’s far from the truth.

“It is very surprising how many discerning foodies will drink mass-produced, highly processed wines without batting an eyelid,” Isabelle Legeron, an educator and consultant who holds the rare title master of wine, wrote in an e-mail. “They just haven’t engaged with wine in the same way, yet.”

For the last two years, Ms. Legeron has held RAW, a fair in London that brings together producers of artisanal and natural wines with others in the trade and the public. All producers who take part are required to list any additives and processing techniques they have used.

The first question might be: Why are wineries so reluctant to document what goes into their wines? Ingredient labeling is voluntary, and very few wineries have stepped up. Bonny Doon Vineyard, Shinn Estate Vineyards and Ridge Vineyards deserve applause as notable exceptions.

Many wineries try to explain away their reluctance by arguing that consumers will be confused by long lists of ingredients, or even a short list of traditional but unexpected substances that have been used in winemaking for centuries. For example, artisanal producers who disdain adding enzymes may still try to clarify their wines with egg whites or isinglass, which is derived from fish bladders. Certainly vegans might want to know that information.

The fact is, some consumers make conscious decisions not to buy products when they see what goes into making them. I don’t want added sweeteners pervading the groceries I buy, for example. I love peanut butter, but won’t buy it if it contains anything more than peanuts and salt. Don’t all consumers deserve the same opportunity to make informed, considered judgments about wine?

At the same time, other consumers — the vast majority — continue to buy processed foods regardless of mysterious ingredients. They are motivated by cost, convenience and sensory gratification, or maybe they just don’t care. No doubt the same will be true with wine.

It’s not apparent whether additives in wine pose public-health risks. Nonetheless, if we want foods that are minimally processed, authentic expressions of what they purport to be (like cheese rather than processed cheese), then we want to be able to distinguish between wines that are relatively unmanipulated and those that are industrial products.

Most wineries have no interest in full disclosure. Just as with food manufacturers, they will have to be dragged into some form of honest representation of their product. Sadly, the responsibility is left largely to consumers to monitor what they buy and drink.

As a first step, it helps to think of wine as food. Concerns about where food comes from and how it’s grown, processed or raised ought to be extended to wine. If we ourselves don’t set standards for quality and authenticity, who will?

The New York Times

 

Read article

Rosè Wine Sales Up 10%

Rose vini It used to be the drink reserved for a hot summer’s day but now consumers are increasingly turning to Rose wine throughout the year with sales up 10 per cent in the last 13 years.

Rose now accounts for a record one in eight bottles of wine bought in supermarkets and off-licences, up from one in 40 in the year 2000.

Sales of rose wine in shops are currently worth £646 million in Britain, nearly £1.8 million a day, according to figures from market analysts Nielsen.

While growth in rose wine buying has slowed in recent years – attributed to poor summer weather – experts believe it is becoming a drink that is enjoyed all year round.

It is especially popular among women drinkers on a night out or sharing a bottle at home with friends.

Some winemakers have specifically targeted women drinkers by making less strong varieties with a typical alcohol by volume level of nine or 10 per cent, compared with other wines which can be up to 14 per cent in some cases.

Twelve per cent of all wine bought outside of pubs is now rose, compared to 2.7 per cent in 2000.

Julian Dyer, general manager of wine distributors Australian Vintage UK, said: “Rose will always have a stronger performance with hot sunny weather, but as it has grown as a category, there are now rose drinkers who are loyal to it all-year round.

“While the wider picture shows we are all still seeing the effects of the recession, there are success stories, such as rose.

“As a category, rose came to the party late so there has always been a precedent for stepping away from the norm and being a bit more forward thinking.

“Winemakers have been successful by listening to consumers who are seeking refreshing wines in lighter and more off-dry styles.

Mr Dyer added: “The rose category is a good example of a wider trend of consumers choosing their wine by style as opposed to country or region of origin.

Martin Green, from Off Licence News magazine, said: “At the turn of the century rose was the Austin Allegro of the wine world – cheap, unfashionable and something you would never want to bring to a dinner party.

“It represented just 2.7 per cent of the UK off-trade wine category and that was mainly used to quench the thirst of young women riding around in pink limos on summer evenings – about as classy as the pink stuff in their plastic cups.

“But like hoodies, iPods, Justin Bieber and the text abbreviation OMG, its popularity rocketed during the Noughties.

“Quality has soared in line with demand as winemakers realise rose’s potential for increasing profits and the importance of producing and marketing rose in its own right as opposed to regarding it as a byproduct of red wine.

“If further proof of its status were needed, Hollywood A-listers are tapping into rose’s new found chic.

“The 6,000 bottle release of Brad Pitt and Angelina Jolie’s first vintage from their Chateaux Miraval estate sold out within five hours – at about £88 per six-bottle case.”

The most popular rose sold in the UK include Californian brands Blossom Hill, Gallo and Echo Falls, while those from Provence in the south of France are gaining in popularity.

Valerie Lelong, of the Provence Wine Council, which exports six per cent of its rose to the UK, said: “The weather definitely has an impact on rose consumption.

“Consumers are keener to drink a wine synonymous with holidays, relaxation and time with friends when the weather is nice.”

The Telegraph

Read article

Armageddon… don’t let it happen in your cellar! (Part 2)

Pressure

During a recent overseas trip, a colleague of mine once again lamented the joys of travelling. This trip kicked off with a baggage issue that ruined her dinner. Other jolly events included fishing her phone out of a toilet, missing a train, almost being run over by an expressionless Parisian, being kicked by a drunken teenager in Lille and finally a screaming taxi driver in Montpellier. Friendly people… the French. But the inside of a fermenting tank can also be a chaotic and even deadly place for yeast.

Modern winemaking can be very stressful and winemakers are putting increasing pressure on their minuscule friends. No, I’m serous! Pressure can indeed be a limiting factor; especially where low pH and high ethanol is concerned. Trapped carbon dioxide gas not only creates turbulence in a tank, but also contributes to a gradual increase in pressure. Pressures upward of 600 kPa (6 atm) typically stop yeast growth (think secondary fermentation of sparkling wine), but not necessarily alcoholic fermentation. In the book “Wine Science: Principles and Applications” by R.S. Jackson, it is stated that a pressure of 3000 kPa (30 atm) and upwards will completely inhibit alcoholic fermentation! What hardy fellows they are, these yeasts!

The use of pressure to control or stop yeast growth is not uncommon in German wineries, but high pressures can cause other problems. Spoilage organisms such as Lactobacillus, Torulopsis and Kloeckera are less sensitive to pressure and can cause a myriad of problems. The latter micro-organism is particularly pesky, as it is quite sulphur dioxide resistant, ferments at temperatures as low as 10°C and can produce high levels of ethyl acetate and amyl acetate.

Some beer brewers postulate that higher pressures have a positive aromatic effect on their ferments, but clear guidelines during vinification have not been established. At least there are many other ways to boost aroma, so don’t be depressed.

 

Bernard Mocke is a technical consultant for Oenobrands

Read article