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Wine Biotechnology Open Day: Opening up to biotec benefits ...
The Winetech Vine and Wine Biotechnology Programme recently held its first "open day" at the Institute for Wine Biotechnology (IWBT) to inform the wine industry about the state of vine and wine biotechnological research in South Africa. KARIN THERON reports.
Biotechnology potentially holds numerous benefits for the South African wine industry, including better planting material and speciality yeast and bacteria. This was stressed by Prof Florian Bauer, of the Institute, who is the programme co-ordinator.
These improved planting materials, as well as speciality yeast and bacteria, he added, are being developed to, for example, reduce the use of water or of agrochemicals and additives and to make the production of wine more environmentally sustainable.
The Wine Biotechnology Programme also aims to help improve the quality of the product, e g healthier vines and wines and better targeted products for niche markets. Biotechnology is not aiming at changing the fundamental processes involved in winemaking, but rather in significantly increasing the choices of viticulturists and oenologists. The additional tools will strengthen their hands in the process of making the wine industry more demand driven, rather than production driven.
Bauer also stressed that biotechnological research is fully integrated with viticultural and oenological priorities. Biotechnology can be seen as one particularly powerful tool to - in the long term - address many of the problems identified by viticulturists and winemakers, and to make wine production economically and environmentally more sustainable.
The open day discussions left little doubt that this technology has immense potential to improve many agricultural, industrial and medical processes, and if used wisely, to generally increase the quality of life across all continents. This, despite the fact that considerable concern has been expressed about the application of biotechnology over the years.
We are in what scientists and sociologists have dubbed "The Century of Biology" and advances in biotechnology are widely expected to fundamentally transform all economic activities. Biotechnology holds unmatched long-term innovation potential and, as such, can also be used as a tool to establish a culture of innovation in, for instance, the wine industry.
The South African government has identified biotechnology as a national priority, as it can:
The South African Wine Industry invested a significant amount in biotechnology when the Institute for Wine Biotechnology was formed at Stellenbosch University in 1995. The Institute forms part of the Department of Viticulture and Oenology in the Faculty of Agricultural and Forestry Sciences.
The wine industry and government, through the Department of Trade and Industry and the National Research Foundation, have together invested about R12,6 million over the past two years in vine and wine biotechnology. The Vine and Wine Biotechnology Programme is one of the main programmes of Winetech.
Several research facilities participate in this programme, including the IWBT, the Institute for Plant Biotechnology (IPB), the ARC Infruitec-Nietvoorbij and other departments at the University of Stellenbosch - in particular the Departments of Microbiology and Genetics.
The Winetech Vine and Wine Biotechnology Programme focuses on grapevine, bacterial and yeast biotechnology.
Wine yeast and bacteria improvement
New yeast strains could give the winemaker many more tools, but in South Africa no GM yeast has yet been submitted for government approval. South Africa's GMO Act, which is in line with international legislation, requires such approval, which has already been granted for various other food items, in particular maize and soy.
In America, a genetically modified wine yeast has received FDA approval and can therefore be marketed and sold. In Europe legislation is under way to give the green light to GM organisms in food with the condition that their use has to be declared on the label.
Several studies showed that a majority of people are open to try GM products. To address concerns, and to fulfil regulatory requirements, the IWBT, together with several international research groups in France, Spain, Portugal and Germany, is intensively assessing possible risks associated with the use of GM wine yeast strains.
By the time the wine industry is satisfied that GM yeast and GM vines are acceptable to consumers, several of these organisms will be ready to be submitted for government approval and be made available to the industry.
These organisms could improve wine in the following ways:
Winemaking currently heavily relies on the use of SO2 to ensure high quality and microbial stability. However, worldwide there is a reduction in the use of chemical preservatives and consumers demand products that are less heavily preserved, healthier, more natural and less processed. Therefore there is a shift towards biological preservatives.
A team of IWBT researchers is busy with the construction of yeast strains that can control the growth of unwanted micro-organisms and will result in wines with lower levels of SO2.
Another approach proposes to develop new yeast strains that synthesise beneficial compounds like anti-oxidants (cancer preventative) in wine.
The days of stuck and sluggish fermentation could be counted if Prof Bauer and his team of researchers succeed in generating yeast strains with enhanced fermentation performance.
Research is being done on wine yeasts that will cause flocculation to occur at the right time or not at all. It will give the winemaker more control over flocculation.
With improved yeast strains, the aroma and flavour of wines with low complexities can be enhanced. By increasing the choices of the winemaker, it provides the opportunity to develop new wine styles.
Also, work is being done on new yeast strains that would better express specific terroirs and to improve colour extraction in red wines. Other projects aim at reducing the ethanol yield of alcoholic fermentation in order to produce wines with acceptable ethanol levels from optimally ripened grapes.
Grapevine Improvement
Prof Melané Viviers from the IWBT explained that the target of grapevine improvement is to produce high quality fruit with reduced susceptibility to diseases and pests and other stress conditions, as well as enhanced nutritional value. They also look at optimal ripening in the grapevine.
According to Prof Johan Burger from the Genetics Department at the US, who leads Winetech's leafroll programme, they are using biotechnology to carry over resistance genes from carnations to Vitis vinifera.
They are also working on "gene silencing", which means that the virus will be inactivated in its replicating stage. As leafroll often spreads from the rootstock to the vine, they are specifically working on rootstock, which means that the vine would be GM free.
Hennie du Plessis and his team from the ARC Infruitec-Nietvoorbij, are specifically working on the rapid, accurate and cost-effective detection of fungi causing black dead arm and Eutypa dieback. This is essential as a grapevine that appears healthy might already have a disease.
What is Biotechnology?
Biotechnology basically entails molecular genetics. Modern biotechnology can be described as genetic engineering and systems biology. Through genetic modification (GM) desired genes from one species are transferred to another species. This would be done to transfer desired characteristics (e g virus resistance) to improve the performance of another species.
In vine biotechnology scientists are at the moment working mainly with tobacco, potatoes, carnations and strawberry plants to try and breed characteristics like virus resistance into vines. Biotechnologists prefer to work with these annuals because the same research can be done in 12 - 18 months using these species, compared to the grapevine where it will take 5 - 6 years. Also, the smaller plants are much easier to propagate in a greenhouse in pots.
Grapevine and Wine Biotechnology entails the integration of molecular and genetic viticultural and oenological sciences. Research projects endeavour to genetically improve wine yeast strains using traditional genetic crosses and recombinant DNA technology. Research also focuses on the development of disease-resistant and stress-tolerant grapevine cultivars with improved characteristics, with the aid of tissue culture and recombinant DNA technology.
Biotechnology is a major issue worldwide. Most people realise that it definitely holds great promises for improving quality of life, but many people are uncertain about what exactly can be done with biotechnology and how far scientists can be trusted to do whatever they imagine in the best interest of all living species.
Biotechnology has been used and accepted for many years in medicine, mining and to dispose of waste, but where humans, animals and plants are concerned, the possible risk of biotechnology is still under scrutiny.
"How far must the application of biotechnology be trusted to ensure a better life for mankind?" This is one of the issues that were discussed at the BIO 2004 international congress held in San Francisco, USA, early in June. Many biotechnologists from the wine industry also attended this important biotechnology congress.
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