20. Specific Options for No- and Low-Alcohol Winemaking

Question 1

What are the three main dealcoholisation method in no/low alcohol wines?

Answer 1

• Reverse osmosis
• Vacuum distillation
• Spinning cone

Question 2

Outline the ‘early method’ of removing alcohol from wine.
Why is it no longer common?

Answer 2

Alcohol boils at a lower temperature than water. The wine is heated to about 78°C. This leads to cooked flavours and the loss of essential volatile aroma compounds.

Question 3

What steps can be taken before fermantion to help lower the fermentable sugars in the production of no/low alcohol wines?

Answer 3

• Choice of grape variety
• Site selection
• Vineyard management
• Timing of harvest
• Blending
• Dilution of must
• Filtration of must

Question 4

What grape varieties are generally not suited for no/low alcohol wine production?

Answer 4

Grapes that accumulate high levels of sugar such as Grenache and Zinfandel because they tend to produce high alcohol wines that require more manipulation.

Question 5

What grape varieties are suited to no/low alcohol wine and why?

Answer 5

Highly aromatic grape varieties such as Riesling and Sauvignon Blanc because they show a strong varietal character even after the de-alcoholisation process.

Question 6

Why are cooler sites better suited for no/low alcohol wine production?

Answer 6

They can slow sugar accumulation and produce grapes with lower potential alcohol levels.

Question 7

Give an example of a vineyard management technique used in the production of no/low alcohol wines.

Answer 7

Reducing the leaf area will limit photosynthesis, therefore controlling grape sugar levels.

Question 8

A producer has a high amount of grapes that have not reached phenolic ripeness in the production of no/low alcohol wines. How can they mitigate this?

Answer 8

Less ripe grapes can be blended with ripe grapes to balance potential alcohol levels with ripe fruit flavours.

Question 9

What are the disadvantages of diluting must in the production of no/low alcohol wines?

Answer 9

Dilution of flavour intensity, colour and tannin.
Not permitted in many countries, including the EU

Question 10

What options does a winemaker have to help to lower the amount of alcohol that is created during fermentation?

No/low alcohol wine production.

Answer 10

• Selection of yeast strains
• Interrupted fermentation

Question 11

Give an example of an alterative yeast strain that can be used in the production of no/low alcohol wines?

Answer 11

Metschnikowia pulcherrima

Can result in reduced ethanol concentration when sequentially inoculated with Saccharomyces cerevisiae

Question 12

What is reverse osmosis?

Answer 12

A membrane separation technique that removes a flavourless permeate of alcohol and water, which can be distilled to remove the alcohol. The watery permeate is then blended back to recreate the wine.

Question 13

What is the most common high tech option of reducing alcohol in wine?

Answer 13

Reverse Osmosis

Question 14

What is vacuum distillation?

Answer 14

A thermal distillation technique that occurs in a vacuum to lower the boiling point. The alcohol is boiled off around 48°C, limiting the loss of volatile aroma compounds. Some of the lost volatile aroma compounds can be captured and added back into the dealcoholized wine.

Question 15

What is a spinning cone?

Answer 15

A thermal distillation device that spreads the wine out to a very thin film. First, volatile aroma compounds are extracted from the wine and then the alcohol is removed. The aroma compounds are then blended back into the wine of the desired alcohol level.

Question 16

How does the dealcoholisation process impact a wine’s volatile compounds?

Answer 16

• Compounds, such as terpenes and esters, are often lost because they boil at a similar temperature to alcohol.
• The amount and type of compounds losst depends on dealcoholication method.
• If a wine is reduced to 0.0% abv, no volatile aroma compounds can be preserved as it’s impossible to seperate them from alcohol.

Question 17

How does the dealcoholisation process impact a wine’s phenolic compounds?

Answer 17

Dealcoholication can affect phenolic compounds such as tannins and anthocyanins. In some cases they are concentrated. (Eg, unripe tannins become very astringent in the final wine).

Question 18

How does the dealcoholisation process impact a wine’s structure?

Answer 18

In most cases, dealcoholized wine will have less body, higher astringency and acidity (due to concentration), and less aromatic intensity.

Question 19

How does the dealcoholisation process impact a wine’s stability?

Answer 19

No- and low-alcohol wines are more susceptible to microbial contamination.

Question 20

What steps can be taken to stabilise no/low alcohol wines?

Answer 20

No/low alcohol wines are susceptible to microbial contamination.

Pasteurization or the addition of a preservative like DMDC (Velcorin) will help stabilise the finished product.

Question 21

What is the typical shelf life of no/low alcohol wines?

Answer 21

It is recommended to consume them within two years if packaged in glass bottles, or one year if canned, as the flavours begin to fade.

Question 22

What are the costs associated with the production of no/low alcohol wines?

Answer 22

Dealcoholizing a wine requires additional time, resources and specialized equipment, which can add significant production costs. High yield loss (15-30%) also significantly impacts cost. However, the alcohol that is removed can be sold separately, and duty rates are often lower.

Question 23

What adjustments can be made post-dealcoholication to correct flavour or textural elements in no/low alcohol wines?

Answer 23

• Sugar (usually RCGM)
• Flavour enhancements; flavourings from Dallant, Essencia, and Laffort may be added to enhance flavour.
• Tannins; Powder or liquod tannins
• Glycerol; To boost body and texture