The wine world is not simply transforming, it is revolutionizing.
The professor Attilio Science on the hot topics of the moment.
Former Director General of the Agricultural Institute of San Michele all'Adige, Full Academician of the Italian Academy of Vine and Wine, winner of the AEI Prize for scientific research in 1991, of the Morsiani International Prize in 2006, of the OIV-Paris Prize in the Viticulture discipline for the best scientific book on viticultural issues and vine culture in 2003, 2008, 2011, 2012 and 2013, author of over three hundred and fifty publications.
Few have the expertise of Professor Attilio Scienza – nomen omen, but who knows how many times they have told him – in matters of wine. With him we decided to discuss the great changes that are involving – and upsetting – international viticulture.
Indigenous yeasts, non-Saccharomyces, spontaneous fermentations. Where did this trend start?
“As has often happened in recent years, the true innovator in the wine sector has been the consumer. The consumer has started the request for a viticulture with greater environmental sustainability and for wines with non-standard characteristics such as those produced with the thermal control of fermentation, barrique and selected yeasts. The production of white wines with the maceration of the skins, sometimes in amphora - the so-called orange wines - the use of spontaneous yeasts and the reduction of sulfur are the production world's response to specific requests from the consumer”.
What has changed?
“Producing wines without using technology is not easy or, at least, it is more risky. Saccharomyces cerevisiae – the only yeast currently used for the production of fermentation starters because it is a large producer of alcohol and low volatile acidity, which are two of the most important qualities that research has developed in yeasts selected by the industry – is being joined by other yeasts with very difficult names such as Torulaspora delbrueckii, Metschnikowia pulcherrima, Saccharomyces uvarum. Usually, due to their modest ability to survive alcohol, these yeasts are active in the early stages of fermentation – to then be replaced by more performing yeasts – but they generate secondary fermentation compounds that are currently highly sought after by the most demanding consumers and are able to reduce volatile acidity. However, it is very difficult to manage spontaneous fermentations and therefore the industry currently produces strains of these yeasts that must be used with the so-called sequential co-inoculation technique together with traditional yeast strains”.
The Consejo Superior de Investigaciones Científicas is experimenting with yeasts that can “breathe” sugars instead of fermenting them, thus reducing the alcohol content even when starting from very sugary grapes. An important result to counteract the increasing alcohol levels due to global warming. What other new frontiers are you working on?
“Even in Italy, work is being done on this topic using the yeasts mentioned above with the sequential co-inoculation technique, but the reduction in alcohol produced is quite modest, around 0,9-1,0% in alcoholic strength. Certainly, this cannot be the only way to achieve less alcoholic wines; it is necessary to implement various practices that involve canopy management, mineral and water nutrition, more precise planning of harvest times, with a medium-long term strategy that leads to the creation of vines that are less efficient in accumulating sugars”.
A word about the recent scandal of the Sauvignon Connection: the “magic” yeast used by some producers in Friuli. Can you explain what it is specifically?
“There is nothing magical about these yeasts, which are the result of crosses between yeasts with different characteristics (obtained without genetic manipulation), capable of enhancing through fermentation some compositional characteristics of the grape such as aroma precursors. In particular, they enhance the varietal compounds called nor-isoprenoids from which many tropical fruit descriptors of Sauvignon or black pepper and spices of Syrah originate”.
And here is the bête noire of winemaking: sulfur. In this regard, what is the project you are developing with the Wine Research Team?
“The reduction of sulfur is not an exclusive objective of winemaking techniques but must start from the management of the vineyard where it is necessary to foresee the reduction of the bacterial load without having to resort to invasive technologies. Among the techniques being tested in the WRT cellars are the careful use of cold, ozone, partial dehydration and ethylene. A very innovative technique is in the pre-application phase that is based on the creation of a DNAChip for monitoring the microbial load of grapes and wine”.
Always with the Wine Research Team you are working on resistant vines, both in terms of drought and disease, a crucial fact given not only the rise in temperatures but also the new parasites and diseases such as flavescence dorée which is little talked about but which is increasingly widespread.
“If we want to react to the changes that climate induces in the vegetative-productive phenomena of the vine, water stress in particular, we must have more efficient rootstocks available (for example, the M series obtained by Unimi through complex cross-breeding programs). Furthermore, if we want to grow vines without chemical treatments, we must introduce disease resistance genes into our wine varieties”.
What techniques can be implemented?
“We can do this by using crossbreeding with American species that carry resistance genes, but the varieties we obtain are not the same as the starting ones (which are Italy's great wealth). Or we can act on their DNA, introducing genes derived from resistant species (cisgenesis) or making the genes present in the varieties we grow (but which, due to various genetic evolutionary mechanisms, are unable to express themselves) express themselves through genome editing; in this case we speak of intragenesis. In any case, these are not GMO organisms (transgenesis) as genes from organisms that are taxonomically very distant are not inserted (for example, inserting a gene from a bacterium into a corn plant to combat the corn borer). For flavescence, the problem is more complex; for bois noir – which is similar to flavescence – resistance genes have been identified in some Georgian vines”.
Resistant vines mean less pesticides and therefore greater respect for the environment. You recently stated that the sustainability of the vineyard begins with respect for the soil. Why is the soil crucial?
“At the origin of this attitude is the agronomic approach of the past that neglected the study of the root systems in favor of the aerial one. Naturally, the fact that the analysis tools of the time could not evaluate the great complexity of the soil in its physical, chemical and microbiological components also played an important role. Due to its complexity, a soil is also subjected to various alteration processes: from erosion to the degradation of the physical structure, to acidification due to leaching of the bases, to salinization, to the reduction of biological activity due to the constant loss of organic substance. These alterations are often irreversible phenomena and, therefore, the soil cannot be considered a renewable resource. The management of the “soil-atmosphere” interface proves crucial in this regard to guarantee a high level of biodiversity in the vineyard because it allows to evaluate the plant, animal, fungal and enzymatic variability as an indicator of the natural balance of the vineyard, thus directing the soil management practices (type of vegetation cover, intervention methods, etc.) and favoring a level of humus capable of giving stability to the soil structure and guaranteeing an energy supply to the food chains. If the soil is the basis of the diversity of wines and shows a high fragility and above all is not renewable, it is necessary to develop conservative strategies that prevent the irreparable dispersion of this heritage”.
What are the challenges of viticulture and oenology today?
“The most important is what is called the anthropological acceptance of research results, which can be partly achieved by democratizing research itself. To achieve this, two actors are essential, which represent a novelty in the viti-enological world. First of all, private financiers, especially wine producers, who with their financial contribution integrate the public one and direct research towards current issues such as, for example, the creation of resistant vines that interest their territories. An effective financing tool could consist of a levy of 2-3 euro cents for each bottle. This way, considerable funds could be raised without much effort on the part of the producers. The WRT producer group and the Winegraft company have already expressed their interest in participating in the Genome editing projects of the Human Technopole of the former Expo in Milan, with their own financing. This crowdfunding tool has already shown great effectiveness in financing innovative start-ups in very different fields. The second actor is represented by companies formed by wineries and cooperatives that will have to deal with the diffusion of genetic innovation and redistribute the proceeds to research. A virtuous example is represented by Winegraft, which has acquired the intellectual property of the creation of the M series rootstocks by Unimi. Winegraft takes care of the diffusion and financing together with the Vivai VCR that have exclusivity in the multiplication and that allocate a part of the proceeds from the sale of the rootstocks to new research”.
But does society seem to be skeptical about this research?
"As has happened in the past, when "revolutionary" genetic innovations are introduced - see the introduction of rootstocks in post-phylloxera reconstruction - society is divided into supporters and opponents, due to the lack of real scientific knowledge in Italy that is not taught in schools. This conflict between humanistic and scientific culture has very distant roots that date back to Croce's idealistic thesis and Gentile's school reform. A fundamental role in illustrating the advantages of this technique is played by communication, as well as by representatives of oenologists (AIEE) and producers' associations, together with some important Italian companies and entrepreneurs such as Angelo Gaja and Oscar Farinetti, as testimonials".
Which wine areas should we keep an eye on for their great potential?
Both in Italy and abroad.
“It is not easy to make medium-long term forecasts given the overall economic instability of the Western world. In Europe, a very competitive country in bulk wines, especially for our southern productions, is Spain. The current trend of global large-scale retail trade to market wine with private labels is pushing many New World countries (Chile, Argentina, South Africa, New Zealand) to sell bulk wine to bottling plants located in many European, North American and Chinese cities. If we have to defend the income of our winemakers, we must reject this approach and sell our packaged wines, tying them increasingly to the territories and large national brands. It is a long-term strategy that will be rewarded. In Eastern European countries, also due to the sanctions and the financial availability of some Russian economic groups, viticulture is developing on large surfaces designed for Eastern markets. While these wines are unlikely to be competitors on our market, they will certainly take customers away from our wines. Our motto for the coming years could be: less wine, of better quality, produced in an increasingly sustainable way.”
Interview for ALEA Evolution, of Irene Graziotto .