Monday, August 26, 2013

How to protect a red wine's color

The juice of many "modern varieties" of grapes (hybrids), and the juice of some vinifera grapes can have extremely deep and vivid purple coloration--glass-staining purple in fact,which is kinda cool. But during the winemaking process, sometimes the color fades to cherry red or even a pinkish rose. What happens?

First, this information is provided by my friend Alex Fullerton, a winemaker:

Anthocyanins (the main pigment in red wine, red cabbage, blueberries, and many other things) are responsible for both the blue color in the grapes' skins and the purple color of the wine. Anthocyanins have a double bond that is formed at one of two different locations of the molecule depending on which location is more favorable, resulting in the molecule having two very different shapes it can take. In high pH it is more favorable for most of the molecules to twist one way resulting in blue hues, while in low pH it is more favorable for most of the molecules to twist the other way resulting in red/pink hues. 

The skins on the Monastrell grape, for example, are alkaline, resulting in a blue color while the wine is more acidic (but not extremely acidic, maybe around pH 3.8) causing a purple color (roughly half of the pigment is blue and the other half is red, red + blue = purple). A very acidic Burgundy, on the other hand, with a pH under 3.5 will appear very red.

And, from Wiki:

Anthocyanins (from the Greek words for "flower" and "blue") can appear red, purple, or blue, depending upon the pH. In flowers and fruits, anthocyanins make the color red, blue, or purple, in order to attract pollinating insects (in the case of flowers) or predators (in the case of fruits, which need predators to eat and then disperse the seeds in the fruit).

OK. but why do some wines see their color fade during winemaking?

This is from an Iowa State article:
In young red wines, the bright red (with purple tint) color is due to monomeric anthocyan pigments which are extracted from the skin during fermentation. During maturation, these pigments are progressively replaced by the polymeric form, which results from the combination of anthocyanin pigments with tannin. Monomeric anthocyanins occur in various forms, such as the red colored flavylium cation, quinoidal base (blue), carbinol pseudo-base (colorless), chalcone (nearly colorless), and as a bisulfite addition compound (colorless). The various forms of anthocyanins are present in equlibrium, which is influenced by pH and other factors. An important point to note is that monomeric anthocyanins are susceptible to bleaching by S02 and with a lowering of pH, the equilibrium shifts from the colorless to colored form.
During maturation, the wine is exposed to air. Oxygen (from air) plays an important role in the condensation reaction between anthocyanins and tannins, which results in the gradual loss of free anthocyanins and the formation of stable polymeric (anthocyanin tannin) pigments. It has been observed that the poiymeric pigments account for 50% of the color density in one-year-old wine. As the wine matures and more polymeric pigments are formed, the color shifts from red to orange and brick red.
The condensation reaction between anthocyanins and tannins is accelerated by oxidation. If condensation continues (due to oxidation), precipitation of coloring matter occurs.
The condensation reaction mechanism includes participation of acetaldehyde under aerobic conditions. The polymerization of pigments also occurs in the absence of air. Oxygen is not involved in this reaction. In the absence of acetaldehyde, copigmentation between anthocyanin and d-catechin has been noted by many researchers.
Summary of all that: So, adding too much SO2 (sulfite) bleaches wine color. pH also plays a role in color (higher pH leads to blue/purple color; low pH leads to red color). When anthocyanin combines with tannin, that reduces color intensity. Oxygenation spurs the process of anthocyanin-tannin combination, which degrades color, but that color loss can occur without oxygen. I note that many winemakers work to limit oxygen exposure during and after primary fermentation; color protection may be one goal of such a practice.
Second, winemakers can add color concentrates to the wine, to darken and enrich its color. Such products (made from richly-tinted grapes) are expensive, and past a threshold they impart objetionable aromas/flavors, and they raise the sugar level too high.
Another method, common in the vinification of Syrah, is to add 5% or so of white grapes to the red grapes during fermentation. It is not intuitively obvious, but this helps to fix the deeper color. (It is also done to improve the Syrah's bouquet.) 
Biochemists continue to try to unlock the winegrape's color mysteries; I am sorry that I cannot find more useful information at this time, but perhaps the above info will be helpful . . .


Sunday, August 25, 2013

Venus grapes

I was out checking chemistry at the Rombough Vineyard in Aurora yesterday. Look at these:


Those are Venus grapes: Seedless, large berries in large clusters. They reached 14.9 Brix in Aurora OR (140' elev) on August 24, 2013. They will get a bit riper but are very edible now. Mild pleasant flavor.

That's an early harvest for this area. Everything will be early if the weather pattern holds, though it has been cooler and  more humid of late. We're at 1643 Growing Degree Days YTD, and it's likely we'll top 2000 but unsure by how much. 2100 or 2200 is in reach if it warms back up.

Tuesday, August 20, 2013

US winegrape plantings not keeping up with demand, so should you jump in?

This article is pretty interesting:

The romantic notion is that it'd be fun to buy and run a winery, to grow your own grapes. Vineyard vistas. Bucolic splendor. A delightful "working retirement." Yes, that is extremely seductive, but like a lot of things, it's an idea which, in actual practice, requires a ton of work (way more than any reasonable human would expect) and throws up constant surprises, many of them negative (grape predators; unforeseen costs; regulatory hassles; difficulty to make good wine; how to sell your wine?, etc.). Many growers say it's a lifestyle you choose, not something you do for profit. For every winery that achieves cult status and can sell its wines at crazy high prices, there are several hundred that struggle to sell their wines at all. Most of them can get along, but a few fail.

Consistent with that backdrop, the US saw an excess of winegrape plantings in the 1990s, which squeezed grape and wine sellers' profits. There has been a dearth of plantings as a result, and so the US will be unable to meet its own rising wine demand. As a result, foreign winemakers are increasing their sales to US consumers. Unfortunately, there are many very good foreign wines that are sold in the US at prices so low that it adversely impacts the US winemakers' abilty to compete.

Over the years I think I've learned some of the reasons why foreign producers can price so low for their U.S. sales. Let's use the Farnese Montepulciano d'Abruzzo as an example--it's priced at $8 or $9 retail in the US, for a good Sangio-like wine, and that includes shipping it from Italy, and markups through our corrupt three-tier distribution system, so you can only imagine how low the price is that the winery receives. So how do they do it?:
a. Sometimes they get government subsidies (New Zealand);
b. Usually the land's been in the family for generations and there's no debt on land or equipment;
c. Usually the extended family members all work in the vineyard and winery, which depresses costs;
d. The "recipe" is locked in and the winemakers fully understand the range of vintage climate, winery situations, and can make quick and correct adjustments without having to defeat mystery;
e. Perhaps the European producers have had enough time to be better at shaving costs and finding synergies; and
f. Sometimes the family has done a good job of marshalling wealth over many generations, and thus can ride out economic downturns, even if it means several years of losses. 

So, might it be a good time to plant grapes in the US? Maybe. But make sure that you can find a market for your wines, at prices you can live with. And too many enthusiastic newbies to grapegrowing just dive in and make numerous mistakes. They plant whatever their neighbor is growing, or, worse, whatever they want to grow (despite the fact that it may not be suited to that climate or soil). They buy too much new equipment. They don't know how to keep young grapes alive. They don't know how to make good wine. They underestimate the costs. They haven't a clue how to market and sell. The best advice is to start a city or suburban vineyard and grow grapes and make wine that way, on a small basis, and learn that way.

Then, if you are confident you can avoid all those obstacles, and if you are ready for 10x the amount of work that you can possibly imagine, and if you've done all your homework and have enough knowledge in all the required areas (viticulture, winemaking, marketing, regulatory, project planning), then OK. Go for it!

Regarding which grapes to plant: Consider hybrid grapes (modern varieties). These are vinifera grapes crossed with American grapes. The result is earlier ripening and better disease resistance. Earlier ripening means less bird predation and (in the Pac NW) a better chance to get the fruit in before the rains return. Disease resistance means less spraying, or (here) no spraying, which saves a lot of time and money as well as being better on the environment. If you pick the right modern varieties for your site, you can make wine that is liked by your customers, and there are dozens of promising modern varieties available. The American grapes sometimes have flavor profiles that take getting used to, but with many of the modern varieties this is only a small step and the vinifera flavors predominate. Also, it is likely that there will be restrictions on spraying (in France and elsewhere, inorganic sprays have rendered vineyard soil completely poisoned and lifeless), and if that happens it will complicate the growing of vinifera. 

Compared to the CA vinifera described in the above article, hybrids are cheaper to grow, but is that enough of a difference to make U.S. winegrape plantings profitable enough? I'm not sure. I'm glad U.S. wine demand is rising but it's unfortunate that it's being met mostly through inexpensive foreign wines. Perhaps the "buy local" movement is a strong enough force that a local customer will pay, say, $12 for your wine instead of $8 for that Farnese Montepulciano.


Monday, August 19, 2013

Bottle Shock

I've been reading about bottle shock. It's relevant because we just finished bottling our group effort 2012 Leon Millot (Epyllion Vineyard). I know that the wine is probably "off" in the bottle now, but after some time it will wake back up.

Pinot Noir is notoriously finicky with bottle shock, or perhaps there are other reasons that it varies in bottle from good to bad to good again.

But science has yet to catch up. What is bottle shock, what causes it, and how long does it last? Is there anything we can do to minimize it?

Articles about bottle shock are all over the map:

This is one of best articles I've found, from winebussiness.com.  But the range of advice is so vast that it only proves that many winemakers are totally clueless about bottle shock (or perhaps the author of the article missed some of their statements). E.g.,
a. Bo Barrett (Ch. Montelena) thinks that putting wine in bottle deprives it of the oxygen that it had received through the pores of the oak barrel, and the result is a growth of Brettamyces (a spoilage organism common in wines in varying amountst) in the bottle. Or,
b. Jeff McBride at Benziger believes that filtering the wine removes phenolic and color compounds which causes bottle shock and takes time to recover through the oxidative process (note: I do not see how removed wine components can recover with time; also, there is a lot of evidence that even sterile filters (with pores small enought to remove yeast) do not have any effect on wine molecules. Or,
c. Stefano Milgotto of WineTech (a mobile wine filtration service) thinks that the culprit is the addition of too much oxygen during the winemaking process. He thinks that filtered wine, right after filtration, sees a loss of varietal character (I would argue that it's not the filtration, it's the oxygenation during filtration, that is the issue.) And:
d. Gordon Burns of ETS Laboratories, seems to have it right: He thinks there is no one cause, but instead there are many root causes, some of which are not understood yet.  He thinks that if the free SO2 in a wine is stable, then bottle shock will be minimized.

Dr. Waterhouse, at UC Davis, says that little research has been done on bottle shock, and this is probably because most winemakers don't worry overmuch about bottle shock because it's always (or almost always) "cured" by passage of time.

He also says that, during bottle shock, bouquet (aroma) is lost because aldehydes are formed from ethanol in the presence of the added oxygen from bottling.

Dr. Boulton, also at UC Davis, thinks that peroxide is the culprit, not oxygen.

And, as to bottle shock associated with wine shipment (or even travel across town for dinner): This may be due to heating and cooling of the wine, which can move air (which is 20% oxygen) in and out of the wine bottle.

And this article suggests that six weeks is a fairly safe time to wait, to see the effects of bottle shock worn off. But some think it's worse with filtered wines, or worse with white wines. Clearly, more research is needed.

Bottom Line: Always let a wine mature before you drink it. This, BTW, is why many restaurants, in their zeal for cash management and lean inventory, commit a double cardinal sin when then offer wines that are too young to drink at prices that are 2.5x to 3.5x normal retail prices. You are overpaying for wine that is too young to drink. Take your own well-aged bottle to dinner, and pay corkage!


Monday, August 12, 2013

Kill Your Lawn

Check this out:

The lawn in the Western U.S. is fast becoming a thing of the past. Water is in such short supply, and Western populations are growing so fast, that many cities are paying residents to take out their lawns. Hundreds of millions of dollars have already been spent by cities in this effort.

This is a wise move, for it conserves scarce fresh drinking water. Keeping a green lawn is a relatively new phenomenon. In nature, grass goes dormant in summer and it greens back up when the heavier rains return. Watering it all summer is contrary to the natural cycle. And using treated drinking water to irrigate grass is doubly wasteful.

And there are many gorgeous drought-tolerant native plants you can choose from, instead.

Have you ever been to the Sierra Foothills AVA (wine region in California) in late summer? The golden (dormant) grass, and green oak tree leaves, and black boulders make for a beautiful sight. The trick is to learn that the natural, seasonal colors of Nature are beautiful.

Dormant grass is not dead; it's just waiting for rain. Fresh water is a scarce resource. Come on! Get with the "Green" mindset. And learn to love the natural colors of nature.

(And a huge benefit: less grass mowing!)



Friday, August 2, 2013

Veraison!

Veraison ("VAY-ray-zaw(n)"--swallow the "n") is the French word for "change." There is no English equivalent, so we use it also.

It refers to the change from the berry-growing phase to the berry-ripening phase.

Normal veraison for winegrapes in the Willamette Valley is about August 12, so having it on August 2 is early. That is consistent with our warmer year in 2013.

So far, so great! for Oregon winegrapes.

The photo is of my Cascade grapes, showing their first turn to color. Regent is also starting to turn. And on the vinifera side, Pinot Noir is turning color in the Valley. Very exciting stuff.