Who Wants to be a Winemaker?

Do you know why two identical grape varieties from geographically similar viticultural areas will turn out different wines? Or, could you correlate a wine’s quality and aging potential to its acidity, pH and sulfite level? And do you know what corrective action would be required to lower the pH in a high-pH wine? How would malolactic fermentation affect this?

Take out a pencil and test your winemaking knowledge using this fun quiz. First warm up with a few fast-finger questions to set you in the mood—a glass of wine will help—and to get rid of stomach butterflies. No one is watching and you have all the lifelines you want. Try the quiz on your own or with friends. See how many questions you can answer without consulting literature, and without peeking at the answers appearing after each question. You can then rate yourself by the scale provided at the end of this quiz.

Ready? Let’s play “Who Wants to be a Winemaker?”

General Questions

1. Put the following northern hemisphere cool-climate viticultural regions in geographical order from North to South.

A. Epernay
B. Niagara Peninsula
C. Beaune
D. Willamette Valley

A, C, D, B

Admittedly, this was a tough question given the close latitudes, but it illustrates why some up and coming New World viticultural areas can produce world-class wines. Epernay is located on the 49th latitude in the Champagne region, slightly north of Paris. Beaune is located on the 47th latitude in the Côte d’Or region of Burgundy. The Willamette Valley is located around the 45th latitude in Orgeon and stretches more than 150 km (94 mi) north to south. The Niagara Peninsula is located on the 43rd latitude between Lake Ontario and Lake Erie around the Canada-US border. Although latitude is an important factor in the viability of a viticultural area, other factors such as micro, macro and mesoclimate are equally important.

2. Put the following phases of a vine’s life cycle in the correct sequence.

A. Bud-break
B. Fruit set
C. Weeping
D. Ripening

C, A, B, D

Weeping is the first phase of a vine’s life cycle following its dormant period during the winter months. In early spring, buds start to appear, and then foliage and shoots develop. The shoots start flowering in late spring followed by fruit set and ripening in the summer months. When the grapes have reached optimal maturity, they are harvested during fall season.

3. Put the following vinification and winemaking procedures in the correct sequence.

A. Malolactic fermentation
B. Cold soak maceration
C. Alcoholic fermentation
D. Destemming

D, B, C, A

This sequence generally applies to red winemaking. Red-skinned grapes are first crushed and destemmed, or vice versa. Cold soak maceration, also known as pre-ferment maceration, is used to maximize phenolic extraction prior to the alcoholic fermentation. Malolactic fermentation can be initiated during or after the alcoholic fermentation but the latter must always be started first.

4. Put the following méthode champenoise procedures in the correct sequence.

A. Disgorging
B. Dosage
C. Bottle fermentation
D. Riddling

C, D, A, B

Bottle fermentation, achieved by the addition of sugar and yeast to each bottle of base wine, is used to give sparkling wine its bubbles. This also causes sediment in the bottle that needs to be removed. The sediment is caused to fall to the neck of the bottle by riddling, or remuage. It is then removed by disgorging to ensure a crystal-clear wine. Prior to corking, a sweet reserve is added to each bottle to balance the acidity according to a desired wine style. This process is known as dosage.

Viticulture

5. Which of the following is not a factor affecting the quality of a vintage?

A. Amount of rain during the growing season
B. Timing of the harvest
C. Type of oak used for barrel ageing
D. Crop thinning

C. Grapes must be harvested when they have reached maturity as well as balance between sugar, acidity and pH. Too much rain during the growing season or harvest will dilute the grape juice, resulting in a poor vintage. Crop thinning, the practice of reducing the number of grape bunches on a vine, is used to improve fruit quality to encourage ripening of the grapes. Oak barrels can affect the quality of a wine but not of the vintage, from a viticultural perspective.

6. Which of the following grape varieties is not a red grape?

A. Zinfandel
B. Cabernet Franc
C. Marsanne
D. Pinot Meunier

C. Marsanne is a popular white wine grape variety in Northern Rhône. Zinfandel can be used to make White Zinfandel, a rosé wine, but it is a red grape. Similarly, Pinot Meunier is a red grape variety often used in making sparkling wines. The juice is pressed with no grape skins maceration. Cabernet Franc is a traditional grape used in red Bordeaux blends.

7. Which of the following is a red-juice grape variety?

A. Pinot Noir
B. Alicante Bouschet
C. Cabernet Sauvignon
D. Syrah

B. All these grape varieties are used to make red wine. Their juice must be macerated with the grape skins to acquire the red color. Alicante Bouschet, however, already contains red juice (it still needs maceration).

8. Which of the following would be the most characteristic of Chardonnay grapes from Chablis?

A. High acidity
B. High sugar content
C. High juice yield
D. High pH

A. Chablis, the northern region in Burgundy, is a cool climate viticultural area. Wines from such areas tend to have a higher concentration of acids due to the cooler growing season that does not always provide enough sugar in grapes.

9. Which of the following grape varieties is not used in making the world-famous champagne wine?

A. Chardonnay
B. Pinot Meunier
C. Sauvignon Blanc
D. Pinot Noir

C. Although Pinot Meunier and Pinot Noir are red grape varieties, they are vinified as white wine and blended with Chardonnay to make champagne wine. Sauvignon Blanc is not allowed.

10. Which of the following organic acids is not found in grapes but which can be found in wines?

A. Malic acid
B. Lactic acid
C. Tartaric acid
D. Citric acid

B. Lactic acid is formed in wines when malic acid is transformed, either partially or completely, through malolactic fermentation. There is no lactic acid in grapes, otherwise. Tartaric acid is always present in both grape juice and wine while citric may be found in minuscule amounts.

11. Which of the following represents the typical water content, as a % of total volume, in grapes?

A. 50-55%
B. 70-75%
C. 75-80%
D. 84-87%

B. Grape juice consists of 70-75% water while wine contains 84-87% water.

12. Which of the following is responsible for the noble rot essential in the making of botrytis-affected wines?

A. Brettanomyces
B. Lactobacillis
C. Botrytis cinerea
D. Penicillium

C. The answer is in the question. Easy! The Botrytis cinerea fungus is responsible for noble rot and is essential in the production of sweet dessert wines such as Sauternes, Trockenbeerenauslese, and other BA (Botrytized Affected) wines. Brettanomyces is a genus of spoilage yeasts responsible for the “medicine cabinet” smell. The Lactobacillis genus comprises lactic acid bacteria responsible for imparting a sour-milk taste to wine. The Penicillium genus is responsible for the undesirable blue mold rot.

Winemaking Techniques

13. Which of the following does not affect the rate or amount of phenolic extraction in red wine production?

A. Fermentation temperature
B. Maceration period
C. Pumping juice over the cap during maceration
D. Bulk ageing in stainless steel tank

D. There is no phenolic extraction during the ageing process when the wine is stored in stainless tanks; however, tannins will soften over time. If the wine is aged in oak barrels, more phenols (tannins) would be extracted.

14. What is the practice of chaptalization used for?

A. To increase the potential alcohol level of a wine
B. To reduce the amount of sugar in wime
C. To stabilize wine against bottle fermentation
D. To increase total acidity of a wine

A. Chaptalization is the practice of adding fermentable sugar to must to increase its potential alcohol level. This may be necessary in vintages where grapes have not ripened fully resulting in grapes with a low-sugar content.

15. Carbonic maceration is used to make what kind of wine style?

A. Sparkling wines
B. Early drinking, fruity wines
C. Organic wines
D. Full-bodied, tannic red wines

B. Carbonic maceration is a rapid fermentation technique used in the production of Nouveau-style wines such as Beaujolais Nouveau. Uncrushed grapes are fermented in a sealed container under a layer of carbon dioxide gas.

16. Which of the following Saccharomyces yeast species is not a species used in winemaking?

A. cerevisiae
B. bayanus
C. beticus
D. diastaticus

D. Diastaticus is actually a beer spoilage yeast species. Cerevisiae and bayanus species are widely used in winemaking. Flor yeasts are part of the S. beticus species and are used in making “madeirized” wines such as Madeira and Marsala.

17. What is the major drawback of the Montrachet S. cerevisiae (Davis #522) strain?

A. Fast rate of fermentation
B. Low volatile acid production
C. High hydrogen sulfide production
D. Low to moderate sulfur dioxide production

C. These are all true statements; however, the Montrachet strain produces an unusually high level of hydrogen sulfide responsible for the rotten-egg smell.

18. Which of the following is not a by-product of alcoholic fermentation?

A. Lactic acid
B. Sulfur dioxide
C. Carbon dioxide
D. Ethanol

A. Alcoholic fermentation results in alcohol (ethanol) and carbon dioxide gas. A small amount of sulfur dioxide is also produced. Lactic acid is produced during malolactic fermentation when malic acid is converted.

19. Which of the following conditions is not a cause of stuck (alcoholic) fermentation?

A. Free sulfur dioxide level is 25 ppm
B. Temperature of the must is too low
C. Brix level is too high
D. Grapes were excessively moldy

A. Free sulfur dioxide (SO2), fermentation temperature, sugar concentration and moldy grapes are all conditions that can inhibit yeast causing a stuck fermentation if thresholds are not respected. A free SO2 level of 25 ppm will not cause a stuck fermentation under normal circumstances.

20. What is the primary purpose for conducting a malolactic fermentation (MLF)?

A. To get bubbles to make sparkling wine
B. To soften a wine’s acidity
C. To convert tartaric acid into malic and lactic acids
D. To increase the alcohol level of wine

B. This is a give-away; the answer was provided in earlier questions. MLF is used to convert the sharp malic acid into the softer lactic acid. The analytical effect is lower TA and higher pH.

21. What is the practice of bâtonnage used for?

A. To age wine in oak barrels
B. To fine wine prior to bottling
C. To stir the lees
D. To tame the yeast to prolong fermentation

C. Bâtonnage, or the process of stirring the fine lees, is used to add flavor and complexity to wine, especially during barrel fermentation.

22. Which of the following is not a process used to lower TA in wines?

A. Addition of potassium bicarbonate
B. Cold stabilization
C. Blending with a wine of a lower TA
D. Addition of sodium carbonate

D. Sodium carbonate, commonly known as soda ash, is a cleaning agent, particularly for plastic materials. It is also used to dissolve tartrates and to neutralize acetic acid. It should never be used as a wine additive.

23. Which of the following procedures will lower the tannin content of a highly tannic red wine?

A. Ageing in oak barrels
B. Filtering using small-micron pads
C. Fining with egg whites
D. Heat stabilizing the wine

C. Egg whites are highly recommended and very effective as a fining agent to soften highly tannic red wines. It has the advantage of minimizing color loss. Oak ageing will further increase the tannin level while filtering and heat stabilization have no bearing on tannins.

24. Why is gelatin generally not recommended for fining white wine?

A. It causes heavy sedimentation
B. It strips the wine of some color
C. It changes the wine’s chemical stability
D. It does not fine well in low tannin wines

D. Tannin may actually be required to be added when fining white wine with gelatin. A silicate-based suspension (eg. Kieselsol) used with gelatin makes a good fining agent for low tannin wines. Gelatin is an excellent fining agent for red wines because of the higher tannin concentration.

25. Which of the following fining agents is recommended for improving color in white wines affected by slight oxidation?

A. Isinglass
B. Casein
C. Pectic enzymes
D. Bentonite

B. Casein can be used to improve color in white wines affected by slight oxidation. Pectic enzymes are used to remove excess pectin that causes cloudiness. Bentonite is a good fining agent that can also be used to inhibit haze in white wines. Isinglass is often used with kits wine where problems are a rare occurrence.

26. What is cold stabilization used for in winemaking?

A. To prepare the must for icewine production
B. To protect the wine from potential freezing
C. To ensure fermentation is not inhibited under cold temperatures
D. To protect bottled wine from tartrate precipitation

D. Cold stabilization is the process of subjecting a wine to cold temperatures for a few weeks in order to stabilize it against further tartrate deposits once bottled. The deposits are from tartaric acid found in all wines. Therefore, this process is also used to lower total acidity in wines.

Wine Analysis

27. A wine’s pH provides useful information on all of the following except one. Which one?

A. Amount of sulfite required to protect the wine
B. Ageing potential of the wine
C. Color stability of the wine
D. Whether filtering the wine is required

D. A wine’s pH provides many clues about its chemical stability; however, filtering has no effect on pH.

28. What is the recommended minimum level of free SO2 to protect a red wine having 12.5% alc/vol, 0.65% total titratable acidity (TA) measured as tartaric acid, and a pH of 3.8?

A. 50 mg/L (50 ppm)
B. 80 mg/L (80 ppm)
C. 100 mg/L (100 ppm)
D. 160 mg/L (160 ppm)

B. The important measurement here is the wine’s pH. A value of 3.8 is too high, and corrective and preventive actions are required. The minimum level of free SO2 required to protect a red wine is calculated as (3.8-3.0)x100=80 mg/L or 80 ppm.

29. Which of the following procedures cannot be used to increase the pH of a low-pH wine?

A. Cold stabilization
B. Double salt precipitation
C. Malolactic fermentation
D. Addition of potassium bicarbonate

A. This is a trick question that requires some logical deductions. First, we need to assume that the TA is either normal or high. Second, we need to assume that the pH is below 3.65—the point at which cold stabilization starts acting on pH in opposite directions. These are logical and fair assumptions. Below a pH of 3.65, cold stabilization actually lowers the pH when potassium bitartrate precipitates.

30. How many grams (ounces) of sulfite (57% SO2) would be required to bring the free SO2 of 19 liters (5 gallons) of a red wine with a pH of 3.5 from 20 to 50 mg/L?

A. 30 mg (1/000 oz)
B. 100 mg (4/1000 oz)
C. 1.0 g (4/100 oz)
D. 30 g (1 oz)

C. We need to increase the free SO2 concentration by 50-20=30 mg/L (30 ppm). Therefore, we need 30 mg/L x 19 L * 0.57 = 1000 mg or 1.0 g (4/100 ounces) of sulfite.

31. Which of the following terms does not relate to acidity when evaluating a wine?

A. Tart
B. Flat
C. Sharp
D. Harsh

D. The term ‘harsh’ is associated with bitterness and astringency.

Wine Faults

32. Which of the following is not a cause of hydrogen sulfide (H2S) forming in wines?

A. Wine has been processed with hydrogen peroxide to reduce the SO2 concentration
B. Wine has been in contact with burnt sulfur deposits in barrels
C. Wine has been left for too long on the gross lees
D. Grapes have been over-treated with sulfur-based vineyard pesticides

A. Hydrogen peroxide can be used to reduce free SO2 concentrations but is not responsible for H2S. H2S is easily detected as a rotten-egg smell. The Montrachet yeast strain is another source of H2S.

33. What is autolysis?

A. Wine spoilage due to oxidation
B. Reduction in total acidity due to organic acid decomposition
C. A condition of extended wine contact on the lees
D. Dissipation of free SO2

C. Autolysis is a result of extended contact of the wine with dead yeast cells. This is essential in the production of sparkling wines. If the contact period is excessive, the dead yeast cells will impart a yeasty smell and taste—considered a fault.

34. What is the cause of the geranium smell (a serious wine fault) in wines?

A. Use of potassium sorbate in malolactic fermented wines
B. Excessive geranium petals were added to try and enhance the wine’s bouquet
C. Acetic spoilage followed by mycoderma
D. Excessive sulfiting

A. Potassium sorbate is a sorbic acid salt that negatively reacts with lactic bacteria when a wine undergoes malolactic fermentation. The result is a geranium-like smell. Geranium petals are never used in winemaking. Mycoderma is the advanced state of acetic spoilage detected as a white film forming on the surface of the wine.

Answers

Congratulations!
Let’s figure out your score. For each correct answer, give yourself one point. Add up your score and rate your winemaking knowledge as follows:

27 to 34: You could run your own micro-winery.
17 to 26: You have above-average knowledge of home winemaking.
9 to 16: You have average knowledge of home winemaking.
0 to 8: You are probably just getting started in winemaking or you need to study some more.

Daniel Pambianchi is technical editor of WineMaker and author of “Techniques in Home Winemaking” (Véhicule Press, 1999).