Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Special yeast reduce alcohol, improve wine

17.01.2014
A team of Australian researchers has taken a giant step towards controlling a growing problem in the wine community. They have identified special yeast that produce a lower level of alcohol, helping to preserve the flavor. Their research is published ahead of print in the journal Applied and Environmental Microbiology.

The alcoholic content of wine has crept gradually northward in the last 10-15 years, from 12-12.5 percent to beyond 15 percent. What might sound trivial to aficionados of hard liquor is seen by some oenophiles as a disturbing trend, threatening the flavor and character of some wines. That, plus issues of public health, as well as taxes (in some countries, on alcoholic content), have created a need for approaches to lowering alcohol content.

The investigation began with a systematic screening of non-Saccharomyces yeast as a means of achieving such a reduction, says corresponding author Cristian Varela of the Australian Wine Research Institute, Adelaide, South Australia. The investigators evaluated 50 different isolates from 40 species and 24 genera for their capacity to produced wine with reduced ethanol concentration. They chose the most successful of these yeasts, Metschnikowia pulcherrima AWRI1149, for experiments in which it was set to work separately on Chardonnay and Shiraz musts.

Once the slower-growing Metschnikowia yeasts had consumed 50 percent of the sugar, S. cerevisiae were added to the mix to complete the process. This "sequential inoculation" reduced the alcohol content in Shiraz from 15 percent to 13.4 percent (and somewhat less in Chardonnay). Controls not inoculated with non-Saccharomyces strains did not produce reduced alcohol content, according to the report.

"The reduction isn't all that great, but it's in the right direction, and with more work, they might get that even lower, perhaps by letting the non-Saccharomyces yeast go longer before you throw in the Saccharomyces, says Alan Bakalinsky, of Oregon State University, Corvallis, who was not involved in the research.

This reduction in alcohol will be of great benefit to the industry says Louisa Rose, of Yalumba and Hill-Smith Family Vinyards, Angaston, South Australia, who is also a director of the Australian Wine Research Institute. "It is using techniques—sequential fermentation—that can easily be used in the winery on a commercial scale."

Previous studies investigating the effects of non-Saccharomyces yeasts on alcoholic fermentation have focused on few species and been concerned principally with the formation of the flavor compounds that might impact negatively on wine quality. None of these led to reductions in alcohol content as substantial as those he reported, says Varela.

The rise in alcohol content in wine has resulted from later harvesting of red grapes. This allows the tannins—responsible for astringency and bitterness—to soften, and in some varieties, it helps minimize the presence of off-flavors, like methoxypyrazines (green pepper/asparagus sensory notes.) But on the downside, the boost in alcohol content reduces aroma and flavor intensity, as well as otherwise impairing the oenological experience. Reducing the alcohol would enable the best of both worlds.

It would also reduce consumer costs in countries where alcohol consumption is taxed, and accede to national and international public health recommendations to lower the alcohol content of alcoholic beverages, such as wine.

A copy of the manuscript can be found online at http://bit.ly/asmtip0114f. The final version of the article is scheduled for the March 2014 issue of Applied and Environmental Microbiology.

Applied and Environmental Microbiology is a publication of the American Society for Microbiology (ASM). The ASM is the largest single life science society, composed of over 39,000 scientists and health professionals. Its mission is to advance the microbiological sciences as a vehicle for understanding life processes and to apply and communicate this knowledge for the improvement of health and environmental and economic well-being worldwide.

Jim Sliwa | EurekAlert!
Further information:
http://www.asmusa.org

More articles from Life Sciences:

nachricht A new potential biomarker for cancer imaging
05.02.2016 | Universiti Putra Malaysia (UPM)

nachricht NIH researchers identify striking genomic signature shared by 5 types of cancer
05.02.2016 | NIH/National Human Genome Research Institute

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Automated driving: Steering without limits

OmniSteer project to increase automobiles’ urban maneuverability begins with a € 3.4 million budget

Automobiles increase the mobility of their users. However, their maneuverability is pushed to the limit by cramped inner city conditions. Those who need to...

Im Focus: Microscopy: Nine at one blow

Advance in biomedical imaging: The University of Würzburg's Biocenter has enhanced fluorescence microscopy to label and visualise up to nine different cell structures simultaneously.

Fluorescence microscopy allows researchers to visualise biomolecules in cells. They label the molecules using fluorescent probes, excite them with light and...

Im Focus: NASA's ICESat-2 equipped with unique 3-D manufactured part

NASA's follow-on to the successful ICESat mission will employ a never-before-flown technique for determining the topography of ice sheets and the thickness of sea ice, but that won't be the only first for this mission.

Slated for launch in 2018, NASA's Ice, Cloud and land Elevation Satellite-2 (ICESat-2) also will carry a 3-D printed part made of polyetherketoneketone (PEKK),...

Im Focus: Sinking islands: Does the rise of sea level endanger the Takuu Atoll in the Pacific?

In the last decades, sea level has been rising continuously – about 3.3 mm per year. For reef islands such as the Maldives or the Marshall Islands a sinister picture is being painted evoking the demise of the island states and their cultures. Are the effects of sea-level rise already noticeable on reef islands? Scientists from the ZMT have now answered this question for the Takuu Atoll, a group of Pacific islands, located northeast of Papua New Guinea.

In the last decades, sea level has been rising continuously – about 3.3 mm per year. For reef islands such as the Maldives or the Marshall Islands a sinister...

Im Focus: Energy-saving minicomputers for the ‘Internet of Things’

The ‘Internet of Things’ is growing rapidly. Mobile phones, washing machines and the milk bottle in the fridge: the idea is that minicomputers connected to these will be able to process information, receive and send data. This requires electrical power. Transistors that are capable of switching information with a single electron use far less power than field effect transistors that are commonly used in computers. However, these innovative electronic switches do not yet work at room temperature. Scientists working on the new EU research project ‘Ions4Set’ intend to change this. The program will be launched on February 1. It is coordinated by the Helmholtz-Zentrum Dresden-Rossendorf (HZDR).

“Billions of tiny computers will in future communicate with each other via the Internet or locally. Yet power consumption currently remains a great obstacle”,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

AKL’16: Experience Laser Technology Live in Europe´s Largest Laser Application Center!

02.02.2016 | Event News

From intelligent knee braces to anti-theft backpacks

26.01.2016 | Event News

DATE 2016 Highlighting Automotive and Secure Systems

26.01.2016 | Event News

 
Latest News

A new potential biomarker for cancer imaging

05.02.2016 | Life Sciences

Graphene is strong, but is it tough?

05.02.2016 | Materials Sciences

Tiniest Particles Shrink Before Exploding When Hit With SLAC's X-ray Laser

05.02.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>