Authenticity issues on the rise at the AWRI helpdesk
Tim Flannery to headline climate workshop
A practical tool for measuring extractable tannins in red grapes
Congratulations to Peter Dry – winner of 2014 Maurice O’Shea award
Results of AWRI Board election
Webinars – new topics and new ways to attend
Easier website access
New search tool
Order the latest AWRI staff publications online
In the last three months the AWRI helpdesk has taken 15 queries on issues related to grape and wine authenticity, provenance, or wine tampering. This brings the total number of this type of query to 19 for the year, a significant increase compared with previous years. Over 750,000L of wine is involved in these cases.
Some of the issues raised include:
- whether a grape variety submitted to a winery has been correctly represented
- allegations of grape/wine substitution or blending with inferior product when submitted to a contract producer
- customer complaint samples returned to wineries with a replacement wine or other liquid filling the bottle
- older wines being declared as younger wines or vice versa
- wines reported to taste different when received after shipping compared to when previously tasted
- allegations of wine doctoring during transport
Several analytical techniques are available to investigate this type of claim but results can sometimes be inconclusive, particularly if holdback samples have not been kept. These include protein analysis of grapes or juice, basic wine chemistry analysis, spectral fingerprinting, mass spectrometric profiling and agrochemical analysis. More work is needed in an Australian context to see if other techniques such as DNA extraction from wine, analysis of strontium isotope ratios or analysis of trace metals can be applied in a rigorous way to demonstrate product authenticity or verify country, region or variety claims.
More information about the specific cases recently encountered and techniques used to investigate them will be presented in an article in the December issue of Australian & New Zealand Grapegrower and Winemaker. Any questions about authenticity issues can be directed to the AWRI helpdesk on 08 8313 6600 or email@example.com.
Prof. Tim Flannery will present the keynote address at the ‘Opportunities in a new climate’ workshop to be held in Penola on Tuesday 11 November. This workshop will continue the program launched in July that is presenting up-to-date tailored information to help Australian grapegrowers and winemakers build more sustainable businesses in a time of changing economic and climatic conditions. A combination of climate experts and industry leaders will present, providing the latest research and policy information as well as practical industry insights. The full workshop program is here. Places are still available, register now.
The AWRI has developed a new method for determining extractable tannins in red grapes that is now available through the WineCloud. Recently published AWRI research has identified that the use of a ‘wine-like’ 15% ethanol extraction method provides a strong indication of the tannin concentration that is likely to result when grapes are made into wine. A rapid measurement method, which involves gentle crushing of grapes by hand and analysis of the extract using UV-Vis spectroscopy, will allow wine producers to access this capability in a practical way.
The concentration of tannins and anthocyanins in red grapes is an important factor in defining the colour and texture of red wines and is influenced by a wide range of factors. These compounds are present in the pulp, skins and seeds of grapes, but the degree to which they are extracted during the winemaking process can vary significantly. Most grape analysis methods use an exhaustive extraction approach to maximise tannin extraction from the grapes. This typically involves the use of high power homogenisation equipment to break up the seeds and skins as much as possible. The reality of the winemaking process, however, is that the extraction environment is much milder and leads to a lower concentration of (predominantly skin) tannins in the finished wine.
Analytical measures for both maximum potential tannin and extractable tannin are now available through the WineCloud and can be used to guide decision-making on processing grapes or aspects such as pressing or maceration. This type of capability could allow:
- More efficient viticultural management and improved harvesting logistics
- More objective fruit grading and allocation
- Enhanced ferment management to achieve desired tannin and colour profile
- Better understanding of factors influencing wine colour development and stability
The WineCloud is a web-based application that can be used to measure and compare a range of attributes in grape and wine samples. Users can generate total tannin, anthocyanin and phenolics data for grapes and wine using their own UV/Vis equipment, by applying a predictive spectral method developed by the AWRI.
For more details, please contact AWRI Commercial Services at firstname.lastname@example.org or (08) 8313 6600.
On 1 October, Peter Dry was announced as the winner of the 2014 Maurice O’Shea award, in recognition of his more than 40 years as a teacher, researcher, editor and writer in the field of viticulture. The prize, awarded every two years, acknowledges an individual, group, corporation or entity that has made a significant contribution to the Australian wine industry. The AWRI is delighted that Peter has agreed to take up the position of Emeritus Fellow at the AWRI following his retirement from his Viticulture Consultant position.
An election was recently held for positions on the AWRI Board in the small and large levy payer categories. The AWRI is pleased to announce that Mary Retallack from Retallack Viticulture has been elected in the small levy payer category and Dr Stuart McNab from Treasury Wine Estates has been elected in the large levy payer category. In the medium levy payer category, only one nomination was received, so an election was not required. Kim Horton, from Ferngrove, is the new Board member in that category.
Mary Retallack is Managing Director of Retallack Viticulture in Adelaide and has worked professionally in the wine industry over the past two decades. Mary is a graduate of the Australian Institute of Company Directors Diploma course, a Fellow of the Australian Rural Leadership Foundation, a past participant of the Wine Industry’s Future Leaders Program, a past Director of Wine Communicators of Australia and a past Non-Executive Director of the Grape and Wine Research and Development Corporation. Mary was the SA and national winner of the RIRDC Rural Woman of the Year in 2012.
Dr Stuart McNab is Chief Supply Officer – Global Wine Production for Treasury Wine Estates, managing all aspects of wine production for a range for brands globally. Stuart participated in the inaugural Wine Industry Future Leaders Program in 2006, has been a member of the Executive of the South Australian Wine Industry Association (SAWIA) and the South Australian Wine Industry Council, was the inaugural Chair of the Wine Innovation Cluster and is a Board member of the Winemakers’ Federation of Australia.
Kim Horton has been Chief Winemaker at Ferngrove in WA since 2003 and has 20 years of winemaking experience. In 2005 Kim was named Young Winemaker of the Year by Australian Wine Selectors. He is actively involved in national and regional wine show judging and has served on the WA Wine Industry Association Technical Committee.
Outgoing Board members are Paul Conroy, John Angove, Dr John Harvey, and Jim Brayne. The AWRI thanks all four for their significant contributions and looks forward to working with the new Board members.
The AWRI’s 2014 webinar program is progressing well, with eight webinars delivered since the start of September. Two new topics have been recently added to the program. Martin Day from the AWRI will discuss the effect of oxygen in pressing and juice handling on 25 November and Andrew Weeks from CCW Co-operative Ltd will share his experience with particle film technology (grapevine sunscreens) on 27 November. In addition, the webinar software used to deliver the program has recently been released as a mobile version, making it possible to attend webinars via a smart phone or tablet. The app is available as a free download for both iOS and Android. For more information on webinars, contact email@example.com.
It’s now even easier to access information on the AWRI website. Areas such as the Winemaking Resources section which previously required a password for access are now openly available. Password restrictions are only being applied to areas where legal restrictions apply, such as Technical Review and the library catalogue, which contain abstracts that are protected by copyright law. It is hoped that removal of restrictions will increase the search engine visibility of AWRI webpages, again making it easier for searchers to find the most relevant technical information.
The AWRI Grape and Wine Roadshow team has been busy over the past few months delivering seminars and workshops across Australia’s winemaking zones and regions. Workshops present practical content on a particular theme, often related to queries received by the AWRI helpdesk. The current workshop – Adapting to difficult vintages – has been developed in response to extreme weather conditions experienced in recent vintages.
In this workshop, participants are provided with information on how to deal with drought, salinity, extreme heat or heatwave events in the vineyard; bushfires and smoke taint; processing ripe fruit in the winery; avoiding stuck fermentations; compressed vintages and associated logistical pressures. Information about growing grapes and making wine in wet seasons with high disease pressure is also provided. The workshop highlights increasing energy costs, limited water availability and the need for sustainable systems in the winery. It also includes a presentation from the Bureau of Meteorology (BOM) on the weather prediction tools available to growers and winemakers. The workshop finishes with an eye to the future through a structured tasting of alternative varieties that might suit each region in a warmer climate. Workshops have recently been presented in New England and Griffith. Upcoming workshops will be delivered in Avoca and Bendigo.
Seminars are organised in conjunction with regional associations and are presented by subject experts. Each association selects the presentations from a range of research topics, to ensure that the seminars are closely tailored to the interests and needs of the audience. Seminars have recently been presented in Murgon, Stanthorpe, Geelong, Macedon, Mt Barker, Pemberton, Margaret River and Swan Valley. Upcoming seminars will be delivered in Griffith, Gippsland, Yarra Valley and Mornington Peninsula.
A new Grape and Wine Search Portal is now available to search across the websites of grape and wine research organisations, peak bodies and state associations across Australia. The customised search engine is easy to use and results can be grouped by organisation or sorted by relevance or date. Add it to your bookmarks for quick access next time you are searching for anything related to the Australian grape and wine industry.
The Australian Grape and Wine Authority (AGWA) recently clarified advice about labelling levels of sweetness in wines exported to China. The updated advice is that while the use of an indicator such as ‘dry’ or ‘sweet’ is not mandatory, if one does not appear the actual sugar level (e.g. 2.5 g/L sugar) must be displayed on the label. This means it is mandatory to include either a sweetness descriptor or the sugar level. Given the difference in sugar testing methods between Australia and China, the inclusion of the actual sugar level may present significant compliance problems in China. AGWA has therefore reviewed its recommendation and now advises that to minimise the potential for compliance problems wine labels include a sweetness descriptor such as ‘dry’, ‘medium dry’ or ‘sweet’.
Accessing the latest AWRI publications is easy. Visit the AWRI Publications web page to:
- View the 10 most recent AWRI staff publications and order the articles online from the AWRI Library
- Search the staff publications database
- Read the full-text of ‘Technical Notes’ from Technical Review (PDF format)
- Read the full-text of ‘AWRI reports’ published in Wine & Viticulture Journal (PDF format).
A full list of AWRI publications published since the last eNews is included below:
1653 Herderich, M., Mayr, C., Parker, M., Baldock, G., Black, C.A., Hayasaka, Y., Francis, L. Glycoconjugates of volatile phenols and smoke related off-flavours in wine. Gougeon, R. (ed.) Wine Active Compounds 2014: proceedings of the 3rd edition of the International Conference Series on Wine Active Compounds, Beaune, France, 26 – 28 March, 2014, 227-230; 2014.
1654 Marangon, M., Smith, P.A. Clarifying the mechanism of protein haze formation in white wines. Gougeon, R. (ed.) Wine Active Compounds 2014: proceedings of the 3rd edition of the International Conference Series on Wine Active Compounds, Beaune, France, 26 – 28 March, 2014, 121-123; 2014.
1655 Francis, L. The ageing of aromas: how complexity develops in wine. TONG (18): 2-7; 2014.
1656 Scrimgeour, N., Godden, P. O2: how closures beat terroir. TONG (18): 20-27; 2014.
1657 McRae, J. Don’t get all hazed over bentonite – help is coming. Aust. N.Z. Grapegrower Winemaker (608): 86-87; 2014.
1658 Coulter, A. Ask the AWRI: Acidity in all its various aspects. Aust. N.Z. Grapegrower Winemaker (608): p. 88; 2014.
1659 McRae, J.M., Day, M.P., Bindon, K.A., Kassara, S., Schmidt, S.A., Schulkin, A., Kolouchova, R., Smith, P.A. Effect of early exposure oxygen on red wine colour and tannins. Tetrahedron DOI: 10.1016/j.tet.2014.08.059; 7 p.; 2014.
1660 Gawel, R., Day, M., Van Sluyter, S.C., Holt, H., Waters, E.J., Smith, P.A. White wine taste and mouthfeel as affected by juice extraction and processing. J. Agric. Food Chem. 62 (41): 10008-10014; 2014.
1661 Forsyth, K. It’s time to check your refrigeration plant. Aust. N.Z. Grapegrower Winemaker (609): 85-86; 2014.
1662 Stockley, C. Ask the AWRI: Export focus on residual metals. Aust. N.Z. Grapegrower Winemaker (609): p. 80; 2014.
1663 Dry, P. Saperavi. Wine Vitic. J. 29 (5): p. 54; 2014.
1664 Curtin, C., Borneman, A., Zeppel, R., Cordente, T., Kievit, R., Chambers, P., Herderich, M., Johnson, D. Staying a step ahead of ‘Brett’. Wine Vitic. J. 29 (5): 34, 36-37; 2014.
1665 Bindon, K.A., McCarthy, M.G., Smith, P.A. Development of wine colour and non-bleachable pigments during the fermentation and ageing of (Vitis vinifera L. cv.) Cabernet Sauvignon wines differing in anthocyanin and tannin concentration. LWT – Food Sci. Technol. 59 (2, part 1): 923-932; 2014.
1666 Cheah, K.Y., Howarth, G.S., Bindon, K.A., Kennedy, J.A., Bastian, S.E.P. Low molecular weight procyanidins from grape seeds enhance the impact of 5-Fluorouracil chemotherapy on Caco-2 human colon cancer cells. PLoS ONE 9 (6): e98921; 2014.
1667 Dry, P., Longbottom, M., Essling, M. Vineyard characteristics used in assessment schemes: theory and practice. Petrie, P. (ed.) Objective measures of grape and wine quality: Proceedings of the ASVO and WISA seminar, 25-26 July 2012, Mildura, Victoria. Adelaide, S.A.: Australian Society of Viticulture and Oenology; 2013: 6-10.
1668 Dambergs, R.G. Validation of an industry vineyard assessment system. Petrie, P. (ed.) Objective measures of grape and wine quality: Proceedings of the ASVO and WISA seminar, 25-26 July 2012, Mildura, Victoria. Adelaide, S.A.: Australian Society of Viticulture and Oenology; 2013: 14-17.
1669 Smith, P. Recent advances in objective chemical measures of wine quality. Petrie, P. (ed.) Objective measures of grape and wine quality: Proceedings of the ASVO and WISA seminar, 25-26 July 2012, Mildura, Victoria. Adelaide, S.A.: Australian Society of Viticulture and Oenology; 2013: 44-49.
1670 Geffroy, O., Dufourcq, T., Carcenac, D., Siebert, T., Herderich, M., Serrano, E. Effect of ripeness and viticultural techniques on the rotundone concentration in red wine made from Vitis vinifera L. cv. Duras. Aust. J. Grape Wine Res. 20 (3): 401-408; 2014.
1671 Kelly, D., Zerihun, A., Hayasaka, Y., Gibberd, M. Winemaking practice affects the extraction of smoke‐borne phenols from grapes into wines. Aust. J. Grape Wine Res. 20 (3): 386-393; 2014.
1672 Hill, G.N., Evans, K.J., Beresford, R.M., Dambergs, R.G. Comparison of methods for the quantification of botrytis bunch rot in white wine grapes. Aust. J. Grape Wine Res. 20 (3): 432-441; 2014.
The AWRI acknowledges funding from Australia’s grapegrowers and winemakers through their investment body, the Australian Grape and Wine Authority, with matching funds from the Australian Government. The AWRI is a member of the Wine Innovation Cluster in Adelaide, South Australia.
The material contained in this publication is comment of a general nature only and is not and nor is it intended to be advice on any specific technical or professional matter. In that the effectiveness or accuracy of any technical or professional advice depends upon the particular circumstances of each case, neither the AWRI nor any individual author accepts any responsibility whatsoever for any acts or omissions resulting from reliance upon the content of any articles. Before acting on the basis of any material contained in this publication, we recommend that you consult appropriate technical/professional advisers.