- Homepage for the Wine Industry

Brettanomyces Economics Survey Seeks More Winery Participants/Feedback

by Ted Rieger
September 18, 2018

The California wine industry is conducting a survey of winemakers worldwide to determine the economic impacts of the wine spoilage yeast Brettanomyces bruxellensis to the wine industry related to costs for testing, management and control measures in the winery; and dollar losses associated with downgrading wine value, or not selling wines, due to contamination and compromised wine quality. The Brettanomyces Economics Survey project is being conducted through the University of California Davis (UCD) Robert Mondavi Institute (RMI) Center for Wine Economics that has conducted similar studies to evaluate the cost to the industry of vineyard pathogens such as Pierce’s Disease and powdery mildew.

The survey project research team seeks additional wine industry participation in the survey, including from wineries outside the U.S. The 20-question survey can be completed online at:


Dr. Torey Arvik, director of applied research with Jackson Family Wines based in Santa Rosa, Calif., initiated the project to determine the dollar costs associated with Brettanomyces, commonly called Brett.

“This is clearly an issue for the wine industry, but to date, we don’t have metrics to quantify the true economic cost of Brett to wineries,” Arvik said. Arvik, a microbiologist with a Ph.D from Cornell University, has worked in winery labs, and formerly worked at ETS Laboratories where he helped develop the test method “Scorpions,” a DNA-based analytical test to detect spoilage microbes in wine, such as Brett. Better analytical technologies are available and continue to be developed to quickly and accurately detect Brett.

Arvik said having a value on the cost of managing Brett and its cost as a risk factor will help winery personnel justify the costs of available new technologies in their budgets to detect and manage Brett, and to determine return on investment (ROI) for purchasing new equipment and supplies.

Other members of the project team include: Dr. Julian Alston, director of the RMI Center for Wine Economics and UCD professor in the Department of Agricultural and Resource Economics; Dr. James Lapsley, UCD viticulture and enology adjunct associate professor; and Jarrett Hart, a UCD Ph.D student in agricultural economics.

The research team released and began circulating the survey in 2017 and plans to continue collecting survey data into 2019. Project goals are to do a case studies on the cost of Brett for individual wineries representing different production levels. Arvik also hopes to work with industry analytical labs to collect anonymous data on the total numbers, types and costs of Brett test services they provide to wineries on an annual basis.

Although a majority of survey respondents to date represent U.S. wineries, other wine producing countries represented include Chile, Spain, Australia and New Zealand. Arvik encourages winery personnel to complete the survey and forward the survey link to wine colleagues in other countries to provide a better picture of the international perceptions and impacts of Brett. The final goal is to complete a report with analysis based on data collected and place an economic value on the cost of Brett to the wine industry.

Preliminary Trends From Current Survey Data

To date, 162 responders have completed the survey, all know about Brett and its influences, and 98 percent of responders make red wines. Wineries represented range from under 500 cases per year production to more than 1 million cases, with bottle price points from under $15/bottle to more than $100/bottle.

Other trends and observations based on current survey data:

  • 73 percent of wineries have seen quality reduction with Brett; 9 percent reported quality improvement.
  • 53 percent of wineries have received negative feedback due to Brett.
  • Half of responders have downgraded a wine due to Brett influence.
  • 13 percent of responders have had to recall a wine due to Brett in bottle.
  • 90+ percent of responders are fearful of Brett and are opposed to it in their wines.
  • 89 percent of responders actively work to manage Brett.
  • 93 percent of responders take active measures to control Brett.
  • 50 percent of responders actively search for Brett and react to it in the winery.
  • Most wineries do more cleaning, acidify for molecular SO2, and use cross-flow filtration to remove Brett.
  • 26 percent of responders have a line item in their budgets to control Brett.
  • 90 percent of responders could save from 1 to 5 percent of operating costs if Brett did not exist.
  • 70 percent test with outside labs, 30 percent test in-house with various methods.
  • 4-ethyl-phenol/4-ethyl-guaiacol (4-EP)/(4-EG) monitoring, and Scorpions are the two most common analyses used to detect Brett.

For more information, contact Dr. Julian Alston by e-mail:

Copyright© 1994-2019 by Wine Communications Group. All Rights Reserved. Copyright protection extends to all written material, graphics, backgrounds and layouts. None of this material may be reproduced for any reason without written permission of the Publisher. Wine Business Insider, Wine Business Monthly, Grower & Cellar News and Wine Market News are all trademarks of Wine Communications Group and will be protected to the fullest extent of the law.