Neuro-enology

It seems that the world of neuroscience is starting to delve into the complexity the winemakers and sommeliers deal with in their profession. How do you describe, dissect, and make decisions involving a product that weaves sight, smell, taste, touch into a poetic symphony?

Any winemaker will tell you that there is no right way, no recipe in vinification. It is just as much an art as a science. But how each person understands the wine as it evolves on a neurological level could potentially be understood scientifically. These advances could shed light on the extremely subjective world of sensory analysis (ie. – wine tasting).

wine tasting brain

“The successive stages of the biomechanics of movement of the ingested wine and transport of the released volatiles will be correlated with activation of the multiple brain mechanisms, apparently engaging more of the brain than any other human behavior. These stages include the initial cephalic phase, visual analysis, ingestion, formation of the wine perceptual image, formation of the wine perceptual object, swallowing, and post-ingestive effects. This combined biomechanic and brain mechanism approach suggests a new discipline of “neuroenology (neuro-oenology),” adding to the contributions that science can make to the enhanced quality and appreciation of wine.”

Here is the full article from Gordon M Shepherd: http://www.flavourjournal.com/content/4/1/19

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The Ecology of Mas de Daumas Gassac

By James Allen, Leonor Gonçalves Frazão, and Hikmet Ataman

Introduction
Mas de Daumas Gassac, a famous “terroir” wine producer in the Languedoc region of France, comprises a total of 150 hectares, divided into 67 vineyard plots separated by forest and garrigue. Most plots are less than 1 hectare in size (about 2.5 acres).
Initial surveys of the site in the 1970s showed many similarities to famous terroir of the Médoc. So the owner, Aimé Guibert, decided to base his wine on a Bordeaux varietal, Cabernet Sauvignon. It has remained their main variety, producing about 80% of the red blend, but twenty other varieties are planted as well. Because Cabernet is not an approved varietal in AOC Languedoc, this choice has restricted their wine to Vin de Pays level. Nevertheless, their bottles price in the “ultra premium” range.

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The first plot visited was the oldest and largest vineyard block. It is a 40-year-old Cabernet Sauvignon parcel, oriented down-slope, with East-West orientation. Between the forest and the winery entrance, facing the Gassac river which crosses the property.
Each of the vines in the domaine is produced from individual cuttings, an uncommon practice these days. Noclones are planted. Field grafting is performed by grafting cuttings from pruning onto the 2-year-old rootstocks already planted. Then, massal selection is done to remove any problematic vines.
Cabernet Sauvignon cuttings were obtained from Chateau Haut-Brion in the Médoc region. They found their soil to be similar to Médoc – composed of detritic glacier rock, sand, and calcareous rocks.
In addition to the soil properties, some mesoclimates (sometimes wrongly referred as microclimates) here are also conducive to the Bordeaux style. The location of many key vineyard plots between the garrigue and the river Gassac has a cooler average temperature than much of the Languedoc region. High day-night temperature difference (diurnal shift) also enhances the quality of the grapes.

Landscape
The river Gassac is a very important attribute for the mesoclimate of Daumas Gassac. Cool air from nearby Terrasses du Larzac drains down to the lower terrain and keeps the ambient temperature lower than the regional average. This is a key reason the consulting geologist and enologist from Bordeaux found the site soattractive back in the 1970s.
Wild boars also find the site attractive. They are a problem because of their location between the Garrigue and river. They prefer certain varietals over others, such as muscat. Electrical fences have been fairly effective against this problem. On the other hand, bird attack is not a problem in this area.
Many of the vineyards of Daumas Gassac were planted on land cut from surrounding forest and garrigue. Planting on razed forest was generally an advantage, but not removing the roots has brought some fungal disease. Before the installation of the vineyard, the roots of the trees were ground into the soil as a measure to increase the organic matter. Luckily, the disease has not spread.
Forest is retained because Monsieur Guibert has the philosophy “for good wine, you must have nature all around”. Hedges are also planted between blocks to prevent spread of oidium. The quality manager, Alexandre Vrolant says the harvest is cleaner with natural ecological presence. Moreover, the company is planting a new plot to preserve and develop vineyard genetic resources. This aligns with their stated values of biological and genetic diversity.

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Daumas Gassac does not have any organic certification, but they spray no herbicides, very few fungicides and some pesticides. The only fungicide that is not organic is the oidium spray.
At this point, no measurement is done to evaluate biodiversity – this is contrary to the behaviour that shows that they are quite conscious that maintainingthe surrounding forest will help to promote natural flora and fauna populations. By planting small plots and not intensively farming they attempt to reach a natural balance.
Sexual confusion to control insects is not currently used in the vineyards, but it’s a project for the near future, according to M. Vrolant. He did also mention that they don’t have major problems with pests. The fact that they will start using sexual confusion in a near future, shows that they are concerned about the topic as well as adopting new ecological practices.
When we ask M. Vrolant the question of “Do tourists respond positively to landscape diversity?” we could not get a clear answer. However, as a group, we all agreed that the biodiversity of this area has a distinctive attraction to the tourists. The natural look of the plots and the richness obtained by the combination of the river Gassac, forests and the vineyards is definitely an impressive advantage to visitors in addition to a valuable marketing tool overall.
Monsieur Vrolant also seemed to say that row orientation decisions are not based on aesthetic appeal, light interception, or erosion control. The practicality of tractor usage or alignment along the space is likely a bigger factor.

Soil quality/management
There is a heterogeneous soil profile throughout the domaine which ranges from calcareous pebbles and silt to red clay and detritic glacial layering. The rootstock Richter 110 is used to deal with the problem of high pH resulting from calcareous soils.

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M. Vrolant says erosion in the domaine is negligible, even in areas with steep slopes. Good soil structure and high organic carbon content could explain this general resistance to erosion.
Young prune wood is reincorporated to the soil to provide organic matter. Old, dead wood is burned to avoid spread of disease.
Fertilization with sheep organic compost was used from the establishment of the vineyards, but in the past five years they have stopped because soil analysis results have shown high levels of organic matter.
There is now a high presence of leguminous flora in the rows that can contribute nitrogen in small amounts by fixing atmospheric nitrogen through root nodules.
To understand the pedological status of the vineyards soil samples are taken at different depths to the first 40cm. Roots can go down to 60cm in these soils, but biological activity is usually between 0-30 cm. Normally every five years is enough for soil analysis because the nitrification rate is around 5% per year. M. Vrolant expressed a desire to make soil pits in future in addition to top/bottom hill soil sampling so the soils could be better understood. At this time copper and bulk density are the main concerns.
In the past, soils were not given a “rest” period before replanting. It is quite standard to do in most vineyards to allow for many soil rehabilitation processes occur. A new viticulturist has just been hired who understands the necessity for this practice.
Weed management is important from different points of view. They don’t use cover crops, but they try to balance and control the weeds so there is minimal competition with the vines. The remaining weeds can incorporate and restitute organic matter within the soil. In addition, they provide housing for some important biodiversity that can help control the pests.
Some superficial discing is performed a few times each year at 30 cm to control weeds, but no herbicides are used. Manual mechanical disruption between vines can be done during winter in problematic zones.
Overall, through tillage practices and weed management they are looking for a decrease in competition between vines and weeds, mainly to increase the yields. This is especially important in older vineyards where yields have started to decline by up to 5% per year.

Water and Energy Use
Like many vineyards in the Languedoc, no irrigation is used at Daumas Gassac, except in one young plot. Water for that plot is sourced from a well and has proven to be clean. The water of the Gassac river is not polluted by any nearby industry, which might be an indicator for surrounding aquifers as well.
Spraying is done based on observation and (about every 2 weeks on average 6 treatments per year). They spray based on two major indicators:  the region risk alert, which is a common practice based on the weather forecast for a specific area, and also on observation. They generally try to spray as less as possible to avoid soil compaction. These practices are generally in line with growers around the world.
Observation is especially important for this site because they are favored with an uncommon mesoclimate for the region, so strategies proposed for the region can’t always be assumed in their vineyards.
Also both the carbon footprint and the litres of water used per liter of wine produced are not measured. These two indicators are very common ecological indicators within the wine industry. So it is likely that future generations managers or owners will change this.
The effects of climate change have been noticed at Daumas Gassac. In the last ten years the harvest date has been getting earlier. Although this could be attributed to other factors, it has certainly been a stated reason for other producers to introduce more “green” practices.
Lack of rainfall in spring is the biggest water problem according to M. Vrolant. Mediterranean climate is known for intensive events of rain during autumn and lack of rain during the spring. Last autumn they had a terrible rainfall event in October that flooded a part of their vineyards, luckily without major consequences.
Irrigation could help to remedy the water deficits in spring. But according to their own philosophy they prefer to not irrigate, which also is understandable regarding their prestige. Overall, M. Vrolant says vine vigor is not a problem.

Air Quality
One positive side-effect of having high proportions of forest throughout the domaine is generally high air quality. Humidity is higher than the region’s average due to the high vegetation and proximity to the river, but there is always a breeze from the higher altitudes of Terrasses du Larzac which keeps the disease pressure low.

Conclusion
Mas de Daumas Gassac is a respected and well-known company in the wine world, considered a “grand cru” of the Languedoc by most wine critics. Their vineyards are skillfully integrated with the distinctive mesoclimate. As a result they are maintaining high biodiversity. Integrating the forests, vineyards, and river in harmony over the last forty years has undoubtedly had a positive effect on ecology and the environment overall.

Implications of the Incestual Relationships between Wine Varietals – By James Allen

According to Patrick McGovern in his book Ancient Wine: The Search for the Origins of Viticulture, “A SINGLE Eurasian grape species (Vitis vinifera L. subsp. sylvestris), among approximately 100 that grow wild in temperate zones of Asia, Europe, and North America, is the source of 99 percent of the world’s wine today.” It is quite remarkable that, of all the wild grape species around the world, only one has gone on to become dominant in agriculture.

As the principal species of wine grapes around the world, the evolution of Vitis vinifera has been studied at length (This et al 2006). Advances in modern genetics have introduced methods which have yielded many new theories as well as shedding new light on relationships between grapevine species and varieties. For example, there are now much clearer distinctions between the genes of different Vitis species that shows clustering linked to geography (Zecca et al., 2011).

Relationships between varietals. (Myles et al., 2011)

Relationships between varietals. (Myles et al., 2011)

But within the cultivated vinifera species, genetic mapping has revealed the entire species to be basically one large pedigree – the result of limited crosses among “elite” cultivars that have been immortalized by vegetative propagation (Myles et al., 2011). But this is likely due to a number of other factors as well.

First degree relationships between "elite" varietals of table grapes and wine grapes in the USDA germplasm. (Myles et al, 2011)

First degree relationships between “elite” varietals of table grapes and wine grapes in the USDA germplasm. (Myles et al, 2011)

Climate changes have been shown to have a major impact on natural selection and diversification. “Species extinction rate due to past climatic and orogenic changes was lower in Asia, higher in North America and highest in Europe” (Ricklefs, 2005). Recently, Wan et al. (2013) discovered that major climate changes in the past have caused spread and diversification of Vitis species that survived the shifts. So, because the pressures of natural selection varied quantitatively and qualitatively in different global regions, it is possible that the progenitors of V. vinifera were selected more rigorously.

Studying the DNA of widely cultivated varieties in comparison to wild grape species has also shown the impact of agriculture and human migration on the evolution of the grapevine. However, there are many conflicting hypotheses regarding phylogeny, speciation events, and biogeographic history of the genus Vitis (Zecca et al., 2011). Indeed, the identification of many “wild” Vitis sylvestris samples had been questioned because of the ease with which they cross and morphological similarities with vinifera. There were likely a multitude of crossover events between the species throughout history (Myles et al., 2011). Answers to these questions might have a valuable use in deciding which direction future breeding or genetic engineering could go.

While the narrow genetic diversity may be attributed to the evolution from few ancient progenitors, human movement and major events linked to globalization have certainly had a major impact as well. The major pest and disease outbreaks in Europe in the 19th century were likely to have drastically reduced the genetic diversity of cultivated and wild grapes just as their most popular cultivars were being spread around the world. Further globalization and commercialization of wine has further narrowed the cultivars outside of germplasm collections (This et al., 2006).

The majority of cultivated varieties today also share a common pedigree due to socio-economic forces through the ages of human agriculture. The reasons for most varieties’ success through history are usually linked to things like sugar content, drought tolerance, and/or yield. The goals of many viticulturists today have changed. So after thousands of years of selection for these traits it may make sense to look to diversity as a solution. Genetic variation is integral to crop improvement (This et al., 2006).

As agriculture advanced vegetative propagation became the norm. With it came the promise of more consistent vineyards and true breeding cultivars but also the loss of a source of unique cultivars from crossing. The market pressure to grow (and subsequently research) only a few, elite cultivars has caused many qualities of those lesser known to go undiscovered (Myles et al.,  2011). These trends of narrowing genetic diversity can make the crops more vulnerable.

Major pathogen pressures continue to plague vineyards around the globe. The most logical way to solve these problems in the long term would be to look more deeply into the “tremendous” natural diversity of Vitis available to us (Myles et al., 2011).

As all vinifera populations have been shown to originate from eastern sylvestris (in the Near East) and most vinifera hybrids to date have been made with North American labrusca (Myles et al 2011), it could be interesting to explore hybridization with genotypes closer to the progenitors. So perhaps the recent increase in Chinese grapevine research due to their emerging wine market could have prospects for improvements and understanding of the current cultivars. Also, the vast germplasm collection around the world could generally be explored in more depth.

Although many other species may hold potential for genetic breeding value, it may be more logical to focus on the current vinifera germplasm and “wild” sylvestris varieties. Genetic evidence supports the idea that vinifera/sylvestris have survived and adapted to the more climatic changes than other species. This could be a clue that they have more evolved genotypes in some very important traits. Human impact has undoubtedly been significant in arriving at the current form of vinifera, but maybe this effect has masked its underlying superiority resulting from the right natural selection pressures. It’s difficult to know because of the unclear origins of sylvestris samples, but future research could explore this possibility.

References

Myles, S., Boyko, A.R., Owens, C.L., Brown, P.J., Grassi, F., Aradhya, M.K., Prins, B., Reynolds, A., Chia, J.-M., Ware, D., Bustamante, C.D. and Buckler, E.S. Genetic structure and domestication history of the grape. PNAS, 108(9): 3530-3535 (2011).

This, P., Lacombe; T., Thomas, M.R. Historical origins and genetic diversity of wine grapes. Trends in Genetics, 22:511-519 (2006).

McGovern, P.E. Ancient Wine: The Search for the Origins of Viniculture. Princeton University Press, 335p. (2003).

Ricklefs, R.E. Historical and ecological dimensions of
global patterns in plant diversity. Biologishe Skrifter (Royal
Danish Academy of Sciences and Letters), 55: 583–603 (2005).

Wan, Y., Schwaninger, H.R., Baldo, A.M. Labate, J.A., Zhong, G.Y., Simon, C.J. A phylogenetic analysis of the grape genus (Vitis L.) reveals broad reticulation and concurrent diversification during neogene and quaternary climate change. BMC Evolutionary Biology, 13:141. (2013).

Zecca, G., Abbott, J.R., Sun, W.B, Spada, A., Sala, F., Grassi, F. The timing and the mode of evolution of wild grapes (Vitis). Mol. Phylogenet. Evol., 62(2):736-47 (2011).

Biodynamics: read only if you care about wine or nature

– By James Allen

For years now I’ve had a dark cloud of questions fill my head any time the subject of Biodynamics came up. Sometimes I would wake up at night, screaming, in a cold sweat from all the hearsay, deception, confusion, and manipulation associated with it. So I thought it was time to dig in and figure out what this philosophical battle is all about.

Basically there are five parties involved: – Rudolf Steiner (the philosopher behind it all) – Demeter (a non-profit formed to put his ideas into practice after he gave a speech in Poland in 1924) – The Growers (putting their blood, sweat and $ in the mix) – The Marketers (using it as a tool to differentiate their wines from other wine) – The Challengers (calling it a hoax and hate how it polarizes the industry)

There is no question that Biodynamics is a huge force in wine right now. It has mystery, “green appeal”, and market-driving force. Many think of it as organic farming tinged with a bit of witchcraft. But to the people who spend the extra effort, time, and money in practicing it on their land it’s worth it. dynamizingOverall, I think it is VERY good. It introduces common-sense philosophies and practices into the vineyard such as biodiversity and nutrient cycling. Teaching a farmer to treat his farm like an ecosystem/organism just makes sense. Germany, known for being logical yet forward-thinking, dominates the trend: accounting for 45% of the world’s biodynamic agriculture.

There is some turmoil and danger involved though. It has potential to distract from other, scientifically proven practices in grape growing and can also bring a false sense of superiority to winegrowers, creating divisions among traditionally friendly neighbors. And it’s definitely more expensive than organic or conventional viticulture. Stuart Smith from Smith-Madrone winery in Napa is the leading opponent of Biodynamics because he’s read Rudolf Steiner’s essays and says (rightly so) that they’re not at all based in science. When a guy who shoots at old cars in his vineyard with shotguns says you’re crazy, you’re in trouble. (for his words go here: http://biodynamicshoax.wordpress.com/) cowhornBUT there is a middle ground. In my opinion, the Demeter organization has gracefully straddled the gap between hippies and scientists. Yes, there are aspects of biodynamics that are really out there, like pruning with the cycles of the moon or the nine “preparations” that are used for fertilizer or disease prevention. (This is where the horsetails and cow horns filled with manure come in). But Demeter does a great job of incorporating actual “Best Farming Practices” into the mix.

Biodynamics can be a very useful tool for encouraging soil, ecosystem, and vine health and therefore enhancing the terroir of the wine and longevity of the vineyard. But it’s also important to integrate a scientific understanding of agriculture with the holistic practices. It is indisputable that, however simple and scientific we try to make it, agriculture will always be complex and mysterious beyond our understanding. So maybe a little well-pondered philosophy can help us team up with nature instead of constantly battling it.

If only the grapes were the whole story…

If only the grapes were the whole story…

I plan on listing all ingredients on my wine label and operating with a philosophy of total transparency. Personally I believe that too much is added to the average wine in the name of “quality control”. Consumers of all wine, from Carlo Rossi to Chateau Petrus are entitled to know what they’re consuming.

That said, the flip side of Asimov’s argument is that consumers are hardly ever educated enough with wine additives to use the information provided to them.

Reading that skim milk, egg whites, tannin, eisenglass (fish bladders), enzymes, etc. has been added to the wine will likely freak most people out. But virtually none of it remains in the wine by the time it’s consumed. The whole reason for adding most of this stuff is to take undesirable stuff out of the wine. Think of it as a specialized, chemical “filtering”. The trace quantities of it that remain, if any, are barely worth mentioning except in the name of honesty.

In a world where all wine, or even all alcohol, is labeled with all the ingredients used in the process, people will almost surely be drinking healthier. If not, they’ll at least know it.