The Art of Wine Making: Choosing the Right Time to Harvest Grapes

As previously mentioned, wine making is a blend of art and science. Another aspect that is often regarded as an art form is choosing the right time to harvest the grapes.

The art of determining when to harvest wine grapes is a crucial skill in winemaking, as it directly impacts the quality and style of the wine.

Here's a quick summary of the factors that winemakers must include when deciding when to harvest:

  • Sugar Levels (Brix) - Winemakers will use technology to monitor the sugar levels of the grapes but have to decide when the best time is for harvesting.

  • Acidity - As grapes ripen, their acidity generally decreases, so winemakers must find a balance between the grapes’ sugar and acidity.

  • Tannins and Phenolics (in Red Wines) - As grapes ripen, tannins change. In the early stages of ripening, tannins may be bitter, but as the grape ripens, they will soften and become smoother.

  • Flavors and Aromas - Winemakers will actually taste the grapes during ripening to monitor the development of flavors and to determine when the fruit has reached the desired complexity.

  • Weather Conditions - Winemakers must be prepared for the possibility of unexpected rainfall or heatwaves, which can affect the quality of the grapes. And, generally speaking, harvest has to happen at the lowest temperatures (e.g., night time) in order to keep the grapes fresh during transport from the vineyard to the winery.

So, harvesting is a decision that involves a blend of science and art. By monitoring sugar levels, acidity, tannins, weather conditions, and the sensory characteristics of the fruit, a skilled winemaker can determine the perfect time to harvest, ensuring that the resulting wine reflects the desired balance and quality. Cheers!

The Art of Wine Making: Determining Which Grapes Will Grow Best

Photo by Martin Katler on Unsplash

As was previously noted, wine making is a combination of science and art. One of the factors that’s considered an art is selecting the right grapes to grow in the right area.

In winemaking, terroir describes the interplay of environmental factors—soil, topography, and climate—that shape the unique characteristics of a wine. By understanding their terroir, winemakers can select the most suitable grapes and ensure a successful and flavorful wine.

Here’s how terroir affects grape choices:

  • Climate: Different grape varieties have distinct climate requirements. For instance, cooler climates are more suitable for grape varieties like Pinot Noir and Riesling, which necessitate a longer growing season and cooler temperatures. Conversely, warmer climates tend to favor heat-loving grapes such as Cabernet Sauvignon, Syrah, and Zinfandel.

  • Soil: The composition of the soil significantly influences the growth of grapes and the flavor profile of the resulting wine. For instance, grapes grown in well-drained, rocky soils, such as those found in Bordeaux, tend to produce wines with more concentrated flavors. Conversely, fertile soils may encourage more vigorous vine growth, potentially leading to wines with less intensity.

  • Topography: A vineyard’s elevation, slope, and sunlight exposure significantly impact grape ripening. Grapes grown on steeper slopes or with south-facing exposure receive more sunlight, which aids in the development of sugar and the grapes’ complete ripening. Consequently, certain grape varieties are more frequently found on specific slopes or elevations within renowned wine regions.

  • Microclimates: Even within a region, different vineyards may have distinct microclimates due to factors such as wind patterns or proximity to bodies of water. These subtle variations can significantly influence a winemaker’s choice of grape varieties to plant.

In summary, winemakers must select grape varieties that are best suited to the specific terroir of their vineyards, as this can significantly impact the quality and style of the wine.

Ever Wonder? What Exactly is in Wine?

We know that wine is a lovely drink made from fermented fruit, but what exactly is in a bottle of wine?

Water

Wine is usually comprised of 80-90% water that is directly extracted from squeezed grapes. In rare instances, water may be added to dilute the wine when the alcohol content (or potential alcohol) and/or phenolics become excessive. However, this practice is quite uncommon.

Alcohol

Between 10% and 15% of wine consists of alcohol, specifically ethyl alcohol (also known as ethanol), which is the primary alcohol component in wine. Other alcohols, such as glycerol and methyl alcohol (also known as methanol), may also be present in wine. Why is alcohol significant in wine? It imparts a “body” and “weight” to the palate, providing a tactile sensation as the wine’s elements linger in the mouth. Ethanol plays a crucial role in your nose as well, as it evaporates rapidly and carries the wine’s aromas up to your olfactory receptors.

Acid

The amount of acid in wine typically ranges between 4 to 8 grams per liter (g/L). To put this in perspective, a bottle of wine is 750 ml or 3/4 of a liter. Thus, a typical bottle of wine has 3-6 gm of acid. This level can vary based on the style of wine, grape variety, and region of production.

Tartaric acid is the most common acid found in wine.

Sugar

Most wines, including common varieties like Cabernet Sauvignon, Chardonnay, and Merlot contain less than 4 g/L of residual sugar or less than 3 gm. Glucose and fructose are the two simple sugars that can be found in equal amounts in the grapes. At harvest, grapes typically contain about 15 – 28% sugar. These sugars are highly fermentable, and the yeast converts these sugars into ethanol, making grape juice into wine.

Phenolic Compounds

This gets a bit technical, so hang in there. Phenolic compounds are tiny molecules, called polyphenols and phenolics and they can really make a difference in wine. Some of these compounds include anthocyanins, flavanols, tannins, and vanilla. We know that vanilla aromas and flavors come from oak barrels and tannins come from the skin, stems, and seeds of the grapes. But, the other compounds affect the wine’s color. Anthocyanins are the ones that give red wine its color. The more anthocyanins there are and the less acidic the wine is, the redder it will be. Flavanols are yellow pigments found in white wines. These compounds are sensitive to light, which helps wine look more golden in warmer climates compared to cooler climates.

So, there you have it! Wine is primarily composed of water, along with some alcohol, acids, sugar, and phenolic compounds. When a wine tastes ‘off,’ it’s typically due to an imbalance in these components. Acquiring the right balance is challenging, which is what makes winemaking such a captivating art. Cheers!

Ever Wonder? How is Wine Made?

Wine making, on the surface, might seem pretty simple. You take grape juice, add yeast and presto, you have wine. And, indeed, a wine maker did tell me that it’s that easy. But, he went on to add, making good wine is not easy!

Wine does begin with grapes. But, knowing when to pick the grapes is very important. That’s because grapes, unlike many other fruits, don’t continue to ripen after being picked. So, you have to get it “right.” And “right” to one wine maker isn’t quite “right” to another wine maker. That’s because some wine makers want slightly under-ripe grapes in order to produce more highly acidic wines such as many white wines and sparkling wine. Other wine makers will choose over-ripe grapes either to produce a sweeter flavored wine or a late-harvest dessert wine. But the vast majority of wine makers are looking for the “Goldielocks” grapes that are just right! These are the grapes that have just the right amount of sugar to ensure proper fermentation.

Once the grapes are picked they are swiftly moved from the vineyard to the winery to ensure they are at peak freshness. White wine grapes will immediately be pressed to extract their juice. Red wine grapes will often go through a sorting process to remove leafs and any other foreign materials and then be de-stemmed. Other wine makers will leave the grapes attached to the stems for added tannin and character.

Next, fermentation begins in tanks made of stainless steel, wood or concrete depending on the style of wine that the wine maker is seeking to achieve. The juice from the pressed white wine grapes goes into the fermentation tanks while the whole grapes or bunches of red wine grape to into the fermentation tanks.

Then comes the yeast. And, we’ll pick up there next time. Until then, Cheers!

Did You Know that White Wine Can be Made from Red Wine Grapes?

Traditionally, white wine is made from ‘green’ grapes and red wine is made from ‘red’ grapes. But, did you know that white wines can be made from red wine grapes?

First, let’s take a quick look at how white and red wines are made. In the production of white wines, the grapes are pressed to extract the juice from the grapes. The juice may undergo additional processes to remove particles so that fermentation begins with clear juice. But, with red wines, the grape juice, skins and seeds are all present for fermentation. Then, the fermented red wine is drained from the tanks either by allowing the wine to freely drain, or by pressing the mixture to extract the wine.

The key to producing a red wine is the time that the red grapes and seeds spend soaking in the fermenting juice. If you simply were to press the red grapes, you’d find that the juice is nearly clear. It’s the skins that impart the color. So, to produce a white wine from a red wine grape, you simply don’t allow for any contact between the grape juice and the skins and seeds. That is, you simply follow the white wine-making process but using red grapes.

One of the most famous white wines that is made from red grapes is Champagne. Traditional Champagne is made from two red grapes (Pinot Noir and Pinot Meunier (Pee-noh Mehr-n'yay)) and one white wine grape (Chardonnay). The Champagne is a white wine because the clear juice from the Pinot Noir and Pinot Meunier grapes are combined with the clear juice from the Chardonnay grape prior to fermentation with no skin contact.

And, other white wines are produced from red wine grapes. Interestingly enough one of the biggest red wine grapes, Cabernet Sauvignon, is being made into a white wine. And that will be the subject of the next Behind the Cork™ wine of the week feature. Look for it! Cheers!