The Vine’s Annual Cycle – from Weeping to Veraison

It’s often said that wine is made in the vineyard and there are several factors that make this true. One factor is the vineyard workers who care and tend for the vines. Another factor is the grape vine. The amazing plant that year after year, through a well-established annual growth cycle, produces the fruit that is made into wine.

What is that well-established annual cycle? After the harvest and during the winter months grape vines are dormant conserving energy for spring and new growth. It’s during the spring that the vine’s annual cycle begins to focus on wine. As the ground temperature begins to rise above 50 degrees, sap will begin to flow upward in the vine and out the tips of the canes (the vine’s branches) that were pruned during the winter months. This is referred to as “weeping.”

Within days, bud break occurs, greenery and tiny shoots emerge from the nodes left on the canes. Over the next one to two months, the shoots and greenery grow into new canes and leaves.

Flowering then begins. Tiny clusters of flowers appear along the canes and since vinifera grapes are self-pollinating, insects are not necessary for fertilization. Each fertilized flower becomes a “berry” and with the immature grapes sometimes being called “berries,” referred to as berry set or fruit set.

Over the following three to four months the vine, taking on water and nutrients and benefiting from the sun will grow the grapes from small, hard, green berries, high in acid and low in sugar to physiologically mature grapes that are higher in sugar and lower in acid. This important step in grape production is known as veraison and is when red grapes begin to color and white grapes become translucent or golden. Harvest is now near and the winemakers take over the responsibility of turning the vine’s hard work into the wine that we all enjoy.

From weeping to veraison—intrigued? Good, and if you like the wine then enjoy it! Cheers!

Do you have a question on wine, submit it to us at office@ocws.org?

 —Wine Education Committee, CL Keedy

Most often, we open a bottle of wine and are greeted with wonderful aromas and flavors that delight our senses and taste buds.  However, on a rare occasion, and sometimes in home winemaking, we encounter less than pleasant aromas and tastes.  Are these considered wine flaws or wine faults – and what is the difference?  What we would most like to know is how to identify these and what causes them. 

To start with, let’s understand the difference between a wine flaw and a wine fault.  A wine flaw is an imperfection in the wine, such as a slight off-odor, minor cloudiness, bubbles or small particles in the wine.  A wine flaw might also include an imbalance with acidity/sweetness, short finish, lack of exceptional aroma or flavor, or color that is slightly off from expectations for that varietal.  These are all considered wine flaws because they are not considered normal for the wine type but they are minor enough that the wine is still drinkable. 

On the other hand, a wine fault is a major deviance from the normal characteristic of the wine and causes it to be undrinkable.  A wine that has developed cork taint is usually so pungent that the wine is undrinkable.  Likewise, a wine that has developed high volatile acidity (VA) will be so sharp and acidic that it too is undrinkable.  These are both examples of wine faults.

The majority of wine flaws and faults can be grouped into:  oxidation, sulfur compounds, microbiological, and environment.  These are often the result of poor winemaking practices or decisions.

Oxidation is the most common cause of wine faults, with oxygen being both a friend and foe in the winemaking process.  During fermentation, oxygen is our friend as it is vital for the yeasts to thrive and perform their job of converting sugar into alcohol.  After primary fermentation, oxygen often becomes more of a foe as it can become the catalyst for numerous reactions including a rise involatile acidity. 

Other common wine faults fall into the Sulfur Compounds category.  Negative sulfur compounds, such as hydrogen sulfide (H₂S), are often associated with the olfactory flaw known as “reduced” notes.  This means that you have a high amount of negative sulfur-based compounds and not enough available oxygen in the wine to mitigate these compounds.  In winemaking, there is a fine balance between a “reductive” environment (“low redox potential”) where H₂S will persist, and an “oxidative” environment (“high redox potential”) where sulfurs will often precipitate out. 

Microbiological faults are often the result of contamination with bacteria or yeasts that have not been inhibited by sufficient sulfur dioxide (SO₂), which serves as an antimicrobial and antioxidant agent in winemaking.

Environmental faults are the easiest faults to avoid by simply ensuring that winemaking and storage facilities follow best practices in environmental controls such as temperature and light.

Below is a description of some of the common wine flaws (if minor) or faults (if excessive):

Oxidation Faults

Sulfur Faults

Microbiological Faults

Environmental / Other Faults

Many of these wine flaws/faults can be avoided altogether by:

• Start with clean grapes and sanitized winery equipment in appropriate environment.
• Make sure that you maintain adequate SO₂ levels in the wine.
• Maintain a low pH (higher acidity) which is more resistant to microbial activity.
• Monitor fermentations (primary, MLF) to completion.

Let’s hope that all your wine tasting experiences will be pleasant without experiencing any of these wine flaws or faults!

– Irene Scott, WSET-3, CSWS
UC Davis Winemaking Certificate 2020
OCWS Wine Education Chair
irene@ocws.org

Many members have enjoyed our previous in-person OCWS Wine Education classes in 2019 and early 2020. Unfortunately, we had to postpone our remaining 2020 in-person classes due to COVID-19. Since the COVID-19 situation is still uncertain, we are going to continue our classes in the webinar format until the time comes when we can hold these classes in person again. Here are some wine education classes that you can look forward to:

· November 8, 2020 (Sunday @ 3 pm): PAIRING WINES WITH YOUR HOLIDAY MEALS—Learn about the 5 basic food tastes and how they impact the taste of your holiday food.

· December 6, 2020 (Sunday @ 3 pm): CELEBRATING THE HOLIDAYS WITH SPARKLING WINE—Discover different sparkling wines with which you can celebrate the upcoming holidays.

· January 10, 2021 (Sunday @ 3 pm): HOW TO TASTE WINE—Learn how to identify the aromas and flavors in your wine.

· February 7, 2021 (Sunday @ 3 pm): WINES OF SPAIN—Learn about the history of Spanish winemaking, their regions and their wines.

· March 7, 2021 (Sunday @ 3 pm): BORDEAUX – WHAT’S THE BIG DEAL?—Learn what makes Bordeaux wines some of the most sought after in the world.

· April 11, 2021 (Sunday @ 3 pm): JUDGE WINE LIKE A PRO—Learn how wine professionals and judges evaluate a wine for its quality.

· May 2, 2021 (Sunday @ 3 pm): AMERICAN WINE REGIONS AND THEIR WINES—Explore the different wine regions in America, its wines and native grape varietals.

After the 2021 summer wine competitions and OC Fair events are done, we can expect more OCWS Wine Education classes to resume in September 2021. Please note that the above topics and dates are subject to change. Additional details will be announced one month prior to class.

If you have any questions or any class suggestions, please contact me at irene@ocws.org.

– Irene Scott, WSET-3, CSWS
UC Davis Winemaking Certificate 2020
OCWS Wine Education Chair

Grapes that are made into wine are often referred to as “Vitis vinifera”.  But are all wine grapes Vitis vinifera?  Can wine be made from grapes that are not Vitis vinifera?  To understand what Vitis vinifera means, we should first understand the basics of Taxonomy, the science involved with the classification of organisms.  We can thank Aristotle for first creating the classification of things as either animal, plant or mineral and further subdivisions based on how they looked or behaved.  However, it was in the 1700s that Swedish scientist Carl Linnaeus developed our current binomial system of Taxonomy.  The Linnaean Classification system has every animal, plant or microbe given a two-part name.  The first part is Genus (broad) and the second part is Species (specific).  Some familiar binomial names you may be familiar with include:  Tyrannosaurus rex, Gorilla gorilla, Saccharomyces cerevisiae, Oenococcus oeni.  Linnaean taxonomic ranks further divided all living things into increasingly more specific divisions such as:  Domain, Kingdom, Phylum, Class, Order, Family, Genus, and Species.

So, with this basic understanding of Taxonomy we know that Vitis is the genus (grapevines), and vinifera is the specific species of this grapevine. Vitis vinifera is a member of the Vitaceae family of woody, climbing vines and is native to the Mediterranean, Central Europe and southwest Asia.

Vitis vinifera is known as the “wine grape” because it is believed to produce some of the best tasting wine.  Most of our well-loved varietal wines belong to this Genus/species:  Chardonnay, Sauvignon Blanc, Viognier, Chenin Blanc, Pinot Noir, Merlot, Cabernet Sauvignon, Barbera, Syrah, Malbec, Grenache, Tempranillo, Sangiovese, Nebbiolo, Mourvedre, Zinfandel, etc.  Our favorite table grape, Thompson Seedless, is also of the Vitis vinifera species and while it doesn’t produce a favorable wine, is great for snacking and dried to raisins.

While the Mediterranean and Europe have their native Vitis vinifera, North America has its own native grape varietals.  The “genus” is the same Vitis, however, the “species” are different from the European vinifera.  Unfortunately, these native American vines often produce a less favorable wine, having an unpleasant “foxy” taste. Because the wines from native American vines are not as pleasant tasting as the European Vitis vinifera, there is less demand and popularity among wine connoisseurs for these varietals.  However, many of these wines are still found in the East Coast or Midwest, where the vines originated from.

The main native American vine species include:

• Vitis labrusca – produces Concord, Niagara, Cayuga, Catawba and Antoinette varieties.
• Vitis riparia – a Midwestern variety that produces Bacchus, Baco Noir, Elvira, Frontenac, Marechal Foch, and Triomphe d’Alsace.
• Vitis rotundifolia – a Southeastern variety that produces the Muscadine grape.
• Vitis aestivalis – a Midwest favorite that produces the Norton grape – possibly the best tasting wine of the native American varietals.
• Vitis rupestris – an Eastern variety with high disease resistance and produces Vignoles, Vidal Blanc, Aurore, DeChaunac, Chancellor (French-American hybrids)

While Vitis vinifera wines may taste better than other Vitis species, they also have roots that are susceptible to the root-damaging louse, phylloxera.  In the late 19^th century, phylloxera devastated the vineyards in Europe when they were accidentally brought in from imported American grapevines.  These American grapevines had long ago adapted to phylloxera and became resistant to the root-damaging louse.

To overcome the damaging effects of phylloxera, many grape growers experimented with cross-breeding of Vitis vinifera and the phylloxera-resistant American varietals.  These varietals became known as “French-American hybrids”.  While these hybrids were successfully phylloxera-resistant, they didn’t match up to the same high quality taste of the European Vitis vinifera. 

To solve this problem, grape cultivators found that they could graft the Vitis vinifera vine onto the rootstock of the phylloxera-resistant native American varietals.  This solution produced the same high-quality tasting European Vitis vinifera grapes on phylloxera-resistant native American rootstocks.  To this day, this is still common viticulture practice for Vitis vinifera vines in Europe, America, and other areas where phylloxera is a problem.  In sandy soils where phylloxera is not a problem, you may still find Vitis vinifera grapevines on their own rootstock (some connoisseurs believe this results in better tasting wine).

So, enjoy your glass of Vitis vinifera, while giving thanks to the native American varietals that saved this great-tasting species from extinction!

Irene Scott, WSET-3, CSWS

UC Davis Winemaking Certificate

OCWS Wine Education Chair

· Most domesticated grapevines have both male and female reproductive structures and are self-pollinated by wind. ^[1]

· The first U.S. AVA region was the Augusta AVA in Missouri. This AVA was federally approved on June 20, 1980, eight months before the Napa Valley AVA in California. ^[2]

· During Prohibition, Alicante Bouschet was the most popular grape varietal for winemaking because of its darker color and its thicker skins allowed for more successful train transportation to the East Coast. ^[3]

· The Norton grape varietal is thought to be the oldest American grape used for commercial production. This grape varietal also has the highest levels of resveratrol – a beneficial antioxidant. ^[4]

· The oldest-known winery is the “Areni-1” cave, discovered in Armenia in 2007. This winery is dated to c. 4100 BC and contains evidence of a wine press, fermentation vats, drinking cups and storage jars.  Scientists also discovered evidence of Vitis vinifera seeds and grapevines. ^[5]

– Irene Scott, WSET-3, CSWS,
UC Davis Winemaking Certificate 2020
OCWS Wine Education Chair

Sources:

[1] Jackson, R.S., Wine Science: Principles and Applications, Fourth Edition, Academic Press 2014

[2] Missouri Wines: History and AVAs, 2018, https://missouriwine.org/about-us/history-and-avas

[3] Lukacs, P., American Vintage: The Rise of American Wine, W.W. Norton & Company LTD, 2000

[4] Wine Searcher: Norton Wine, 2015, https://www.wine-searcher.com/grape-901-norton

[5] Wikipedia: History of Wine, https://en.wikipedia.org/wiki/History_of_wine

Summer is finally here!  With summer comes sunshine, warm weather and most likely some poolside/patio wine drinking with friends.  So, what are some good choices for your summer wine drinking that will keep you cool and refreshed?  The key to great summer drinking wines is that they have a lighter body and a higher acidity.  These wines will be refreshing and delicious when served chilled.  Yes, even light-bodied red wines can be delicious when served slightly chilled.

When referring to a wine’s “body” it usually refers to a feel of “weight” in the mouth.  Imagine the different mouthfeel you would experience with water or non-fat milk, then 2% milk, and finally full-fat milk or cream.  This comparison will help you begin to understand what “body” means in wine.  Most varietal wines have a “body” that is typical for that grape varietal.  Wine components that increase a wine’s “body” or “fullness” include sweetness, glycerol, grape and yeast polysaccharides, and phenolic content (in red wine).  On the other hand, the perception of “fullness” can be decreased by acidity.

Acid is one of the main chemical constituents of grapes and gives wine “structure” and the ability to age well.  The main wine acids are the non-volatile organic acids such as tartaric and malic acid which constitute more than 90% of the grape’s acidity.  Malic acid is what you taste when you bite into a crisp apple.  Tartaric acid is that tart taste when you eat grapes (as it is the primary acid in grapes).  While acid can be tasted by taste buds all over your tongue, it is commonly strongest along the sides of the tongue and can often cause increased saliva production.  High acidity or astringency in wines is often balanced with a little sweetness (or perception of) – this is referred to as a “balanced wine”.

With grapes grown in warm or hot climates, the heat will metabolize malic acid such that little is left by harvest – giving wines a lower acidity in warmer climates.  However, cooler climate grapes will often retain more of their malic acid by harvest – giving grapes grown in cooler climates a higher acidity.  In addition, some grape varietals are naturally higher in acidity than other grape varietals. If a wine undergoes “malolactic fermentation”, the stronger malic acid is converted to a softer lactic acid.  Overall, it is the tartaric acid that ends up giving wine most of its taste of acidity.

Based on this understanding of body and acidity, we can choose some nice, refreshing summer wines.  A great guide to grape varietal acidity and body is the “De Long’s Wine Grape Varietal Table” (https://www.delongwine.com/products/wine-grape-varietal-table).  This table is a visual reference to various varietals and their body/acidity levels.  We can see on this chart that the Albariño, Aligoté, Colombard, Grüner Veltliner, Pinot Blanc, Torrontés, Riesling, Sauvignon Blanc, Verdelho, Verdicchio, and Vermentino varietals all typically have a lighter body and high acidity.  Any of these would make a cool, refreshing summer white wine.

Want to drink a red wine on a hot day and still be refreshed?  Choose a red wine with a lighter body and higher acidity (avoid wines with heavy tannins), and serve it slightly chilled (about 55^oF).  A Pinot Noir is a great example, along with, Barbera, Blaufrankisch, Dornfelder, Freisa, and Sangiovese.

Rosé wine is also an excellent choice for summer with its light body and crisp acidity.  Most Rosé wines have higher acidity as they do not undergo malolactic fermentation where the stronger malic acid is converted to weaker lactic acid.

Sparkling wine is also a great choice for your summer wine – and not just because the bubbles are so fun!  Grapes that are destined for sparkling wines will be picked earlier than other grapes (for still wines).  These grapes will often be picked when the Brix (sugar) level is 18^o-21^o so that they retain their tartness and acidity that is needed for sparkling wine.

To ensure that you have a wine that has retained a crisp, refreshing acidity, choose a wine from a cooler, fog-drenched region.  Cooler climate wines will retain more of the malic acid that might otherwise become degraded in the heat.  Some excellent cooler-climate wine regions in California include:  Sonoma Coast, Russian River Valley, Monterey, Santa Barbara County and others.

I hope you enjoy a cool, refreshing wine at your next summer poolside party!

Irene Scott, WSET-3, CSWS
Winemaking Certificate, UC Davis
OCWS Wine Education Chair

Our wine education seminars have been such popular events this past year! In early 2020, many of you have enjoyed our seminars on: “Intro to Wine and Wine Tasting” (January) and “Wine, Chocolate and Other Perfect Pairings” (February).

We are disappointed that due to COVID-19 we had to cancel our remaining 2020 seminars on “Wines of Spain,” “Wines of Germany & Austria” and “Wines of North America.”

However, as soon as conditions permit, we will re-schedule these, and more wine education seminars. We may have smaller class sizes and will need to follow guidelines for social distancing, but rest assured, there will be plenty of wine tasting!

Thank you for your patience and understanding. We will notify you as soon as we can safely reschedule these seminars.

– Irene Scott, Wine Education Chair