Wines Enology Grape Chemistry Lab at Virginia Tech

Enology Notes

Wine/Enology Notes # 89 May 27, 2004

To: Regional Wine Producers

From: Bruce Zoecklein

Subjects: Norton Roundtable, American Society for Enology and Viticulture – eastern section meeting, Laboratory Services, and Research and Extension at a Crossroad (continued)

Norton Roundtable. We will conduct a Norton Roundtable meeting on July 26, 2004, at Chrysalis Vineyards at 1:30 PM. If you are interested in attending, please RSVP via an email note to .

The meeting is designed as a forum for discussion of the viticultural, enological and marketing issues related to the production and sale of Norton. It will include sensory evaluations. Topics will include:

  • Norton and stylistic goals
  • Canopy management, and its relationship to wine style and balance
  • Norton vine nutrition issues
  • Maturity evaluators and yield
  • pH, TA and phenol management
  • Structure/texture balance
  • Processing techniques: whole cluster press, cold soak, enzyme treatment(s), yeast and MLF selections, fermentation temperature, co-fermentation, tannin additions, delestage, wood fermentation, sur lie storage, wood storage time and sources(s), microoxgenation, etc.

Please bring Norton wines to share and discuss, if you can, and don't forget to RSVP. We will evaluate some microoxygenation trials done on 2003 Nortons.

American Society for Enology and Viticulture, Eastern Section, Technical Meeting and Symposium. In July 2004, the ASEV/ES annual meeting will once again convene in Virginia. The venue will be the Hotel Roanoke and Conference Center (, a short drive from spectacular scenery, the Blue Ridge Parkway, and some of Virginia’s finest wineries. Half-day Technical Sessions are scheduled for 14-16 July 2004, with the balance of each day focusing on a “Grapes, Wine and Environment” Symposium.

The underlying goal of the symposium is to explore how soils, climate (particularly temperature), and cultural practices affect fruit and wine composition and quality, especially in a warm, humid environment. Featured Symposium speakers will include Kees van Leeuwen, Erland Happ, Gregory Jones, Phil Freese, Zelma Long, Andrew Reynolds, and Daniels Granes. For more information, see the Wine/Enology-Grape Chemistry Group website at and Enology Notes #87.

Laboratory Service. The Wine/Enology-Grape Chemistry Laboratory conducts supplemental, quality control analyses for the Virginia wine industry. This service is designed to support, not replace, in-house analyses.

We provide protein, bitartrate and microbial stability analysis and trouble-shooting. HPLC analysis for organic acids (used mainly for monitoring MLF status) is conducted by the Wine/Enology-Grape Chemistry Lab on the first and third Wednesday of each month.

Through the Virginia Wineries Association, we are exploring means of increasing the service.

One of the options we are evaluating is the use of Fourier Transform Infrared (FTIR) Spectrophotometry. British scientist Peter Fellgate recognized that all infrared wavelengths travel at the same velocity. This results in the simultaneous absorption of radiation by different components in a sample. Changes in the chemical composition of the sample will result in a change in the absorption characteristics. The French mathematician Joseph Fourier developed the mathematical procedure to calculate these differences.

Thus, the analysis of ethanol, TA, pH, reducing sugars, etc. can now be measured in approximately 30 seconds, with precision and accuracy as good as conventional methods.

FTIR systems are commercially available, although expensive. While working in California and Europe, I have been evaluating FTIR. It is hoped that in addition to wine chemistry, non-invasive analysis of fruit could be conducted, such as color and skin-tannin maturity. FTIR may be a way to increase our laboratory service and to provide a rapid turn-around.

Research and Extension at a Crossroads (continued). As indicated in the previous edition, there was an excellent article written by Dr. Cliff Ohmart in the March 2004 issue of Wines and Vines. The article, titled “Research and Extension at a Crossroads,” discusses the decline in publicly-funded agricultural research and extension, and the short- and long-term consequences.

The good old days of adequate public funding of agricultural research and extension may be over. The question is-What will the US and regional grape and wine industries do about this? Read this informative article.

There are several industry and academic groups attempting to deal with the problem. One such group, WineVision, has layed out the following objectives for the US industry:

Strategic Priority I

Become the leader in sustainable practices – environmentally, socially and economically

Enroute Objectives

  1. Develop and facilitate wine community adoption of a broad-based voluntary code of responsibility and encourage support from the rest of the supply chain.
  2. Anticipate and avoid future sustainability problems.
  3. Invest in research to build the sustainable infrastructure.

Strategic Priority II

Make wine an integral part of the American Culture

Enroute Objectives

  1. Expand the acceptable wine occasions across the demographics of alcohol-consuming segments.
  2. Define a public identity for the American wine community.

Strategic Priority III

Position U.S. wine as the high-quality high-value product (across price points) in global markets targeted for the greatest prosperity

Enroute Objectives

  1. Develop and implement a U.S. wine positioning strategy (e.g., high-quality, high-value product across price points).
  2. Facilitate broader and easier wine community distribution to global markets.
  3. Reduce or eliminate tariffs in 50% of the producing and non-producing nations.
  4. Reduce or eliminate trade barriers in more than one-half of the U.S. market.

Strategic Priority IV

Enhance community-wide coordination and communication

Enroute Objectives

  1. Enhance wine community-wide coordination and improve intra-wine community communication.
  2. Improve domestic and global wine community marketplace information.

We are looking at methods to address a growing crisis in funding for research. The key objectives include:

  • Identify the key external conditions that will impact future grape and wine research.
  • Develop a vision for best case future working relationship between industry and academia.
  • Identify major issues/barriers to achieve the vision.
  • Test the willingness of both industry and academia to mutually tackle identified barriers.
  • Create a permanent ongoing working relationship and structure to tackle the barriers over the next several years.
  • Identify initial strategies to jointly address the growing crisis in research and outreach activities.


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Dr. Bruce Zoecklein
Professor and Enology Specialist Head Enology-Grape Chemistry Group
Department of Food Science and Technology, Virginia Tech
Blacksburg VA 24061
Enology-Grape Chemistry Group Web address:
Phone: (540) 231-5325
Fax: (540) 231-9293