At a glance:
Alcohol content and consumer liking. Wines made from Cabernet Sauvignon grapes harvested at five different maturities showed a range of alcohol concentrations from 11.8% v/v to 15.5% v/v. Consumer preference was similar for wines containing 13.6% v/v to 15.5% v/v indicating that harvesting earlier could deliver a wine that consumers prefer or like just as much as a fuller and hotter style wine and which contains 2% v/v less alcohol.
content of alcoholic beverages, including wine, and the taxation regimes associated with such products. A number of approaches and technologies are available for producing wines with lower alcohol, and indeed a range of lower-alcohol wines is already available on the market. A holistic approach to producing lower-alcohol wines can be undertaken to ensure the lower-alcohol product delivers desired sensory attributes such as ‘texture’, ‘fullness’ and ‘warmth’; attributes associated with superior quality. There are several strategies across the value chain for reducing alcohol concentration in wine including: • Viticultural practices such as decreasing the leaf area to fruit weight ratio in order to lower sugar concentration in the berry, and harvesting earlier therefore picking grapes with lower sugar content. • Fermentation and winemaking practices including blending of earlyharvested low sugar grapes with
grapes with greater maturity and use of wine yeast inoculation strategies and yeast strain selection to produce less alcohol. • Post-fermentation practices and processing technologies, which include wine blending of high and low alcohol wine, and physical removal of alcohol after fermentation. For more details on strategies to decrease ethanol concentration in wine see AWRI publication #1214 Controlling the highs and the lows of alcohol in wine and AWRI factsheet Reducing alcohol levels in wine available on the AWRI website (www.awri.com.au).
MATURITY TRIAL Delaying harvest can produce grapes not only with fuller flavour but also having reduced green characters; considered especially true for Cabernet Sauvignon and related varieties. It is commonly assumed wines made from such grapes will be preferred by consumers. However, this is not necessarily the case.
• Major retailers in the UK such as Sainsbury’s have said “by 2020 we’ll double the sales of lighter alcohol wine and reduce the average alcohol content (ABV) of own brand wine and beer”. • Increasingly, health concerns linked to alcohol consumption shape both national and international public health recommendations to lower the alcohol content of alcoholic beverages, including wine, and the taxation regimes associated with such products. • A number of approaches and technologies are available for producing wines with lower alcohol, and indeed a range of lower-alcohol wines is already available on the market. • Choosing the right yeast strain can impact on ethanol yields in the final wine. Commercially available wine yeast (S. cerevisiae) strains show very similar alcohol production efficiencies. • Generating GM low-alcohol yeasts has proven the concept yeast can play a significant role and inspired the development of non-GM lowethanol strains. In addition, nonconventional strains have been identified which show great potential for producing wine with reduced alcohol concentration.
In a sequential harvest trial, undertaken by the AWRI, Cabernet Sauvignon grapes were picked at five sequential maturities to deliver wines with a range of alcohol contents from 11.8% v/v to 15.5% v/v. Although overall fruit flavour, dark
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