In Vino, Veritas – or In Wine, Truth – by Pliny the Elder

When the Holy Roman Empire was forming Charlemagne gave lands to the monks in order for them to plant vineyards to make wine for the Eucharist. Those first vineyards, planted by Benedictine monks, make some of the classic wines of all time.  Wine was in France centuries prior to Charlemagne, but it was those monks that we have a provenance of today’s wine. It was also from those Monks that we get the concept of terroir.

Today terroir is the “in” thing that wine sommeliers will talk about. One of the myths is that you can taste the soil of the wine.  This traces back to those monks who would taste the soil in order to determine where the best wines would come from. What those monks didn’t know was that the vines get their ingredients from carbon dioxide and sunlight.

Wine geology is complex, and recently Alex Maltman, a distinguished professor emeritus of geology published a book about the geology of wine.  His book: Vineyards, Rocks, and Soils The Wine Lover’s Guide to Geology, is a reference guide for those who want to know more about the geology of the wines they are drinking

Dr. Maltman was also a guest on the podcast where we talk about wine geology and dispel the myth about tasting the soil.

Dr. Maltman notes that the chalk of Champagne is the soil and the soil is important to drainage of the vine, but the plant doesn’t take up chalk (which is a silicate compound) and when the inorganic compounds of chalk are broken down and some of those minerals are taken up they are tasteless.

What people taste are the many organic compounds that the plant makes from the carbon from carbon dioxide through photosynthesis, and coded on the vineyards DNA. You also taste the byproducts of fermentation – as those compounds are put through yeast, bacteria. Where the confusion lies is that some of the organic compounds of the soil smell like some of the products of fermentation of the wine.

The monks didn’t know about photosynthesis, nor did they know about DNA encoding for the proteins and organic chemicals, nor did they understand the complex chemistry of fermentation. They just knew wine is delicious- and sometimes the soil tastes a bit like the wine, so they assumed that the vine took up the soil and put it into the grape (the wine takes up the water, not the soil).

Today Sommeliers everywhere love to talk about geology of where the wine you are buying came from. They love telling you a story – because we love stories about our food. As Maltman points out, we love to know the provenance of our food and in an era of large multinational corporations, wine is one of the few places you can know about where a grape was grown, harvested, what were the conditions that year, what is the make up of the land – even what side of the mountain that wine came from.

But what you cannot taste, is the soil from the rocks. That, my friends, is not only impossible because of how and what the plant takes from the soil (water and ionic forms of inorganic compounds as Maltman points out in his book) but ignores the most glorious and complex part of wine.

In our conversation Maltman talks about the grapes that no one has heard of that are making a comeback in Greece, Croatia, and Eastern Europe.

Oh and we bust the myths of resveratrol and people who want to add this as a supplement for weight loss, long life, etc.

I hope you enjoy this week’s podcast. Distributed by Simple Media and produced by Producergirl Productions.

Read the full transcript below.

Terry Simpson: The Sommelier was describing the terrior of what turned out to be a tasty Burgundy Beaujolais. He impressed me with his knowledge of the amazing soil in this region of Burgundy, and when I asked him what I’d be tasting in the wine, he said I was tasting the soil. To think that 1300 years ago, Benedictine monks were given that land by the Emperor Charlemagne with the purpose of planting vines to harvest wine for the Eucharist. When they were trying to determine where they were going to plant the vineyards, they would taste the soil because they believed that the best soil made the best wine, and from that soil came the taste. So I wondered as I was tasting this wine, was I tasting the soil?

Alex Maltman: No. In a word, no.

Terry Simpson: So who is this who would dare defy the convention that we can taste the soil in wine?

Alex Maltman: My name’s Alex Maltman. I’m Professor Emeritus now because I’ve retired from the University here in Aberystwyth within West Wales, U.K. And I’ve been a geologist all my life and been all kinds of things, but I’ve grown grapes for a lot of years and made a good wine at home, but always I’d ask questions about why things are being done in a certain way. And I got more and more into the science behind wine, and in particular the vineyard geology. So now that I’m pretty much retired I can indulge more into thinking about vineyard geology.

Alex Maltman: Looking at the kinds of things that are written about this kind of thing hence eventually led to this book, ‘Vineyards, Rocks, and Soil: The Wine Lover’s Guide to Geology’, Oxford University Press, which just came out a couple of months ago and I’m pleased to say is getting pretty good reviews.

Terry Simpson: My name is Dr. Terry Simpson and this is my podcast, Culinary Medicine: Food Cons and Food Conversations, where we have conversations about food as medicine, and discuss food cons, exposing myths, cons, and mountebanks.

Terry Simpson: Wine is a hot topic not only in my field of culinary medicine, but even more from the wine lovers among you. Wine clubs abound, delivering different wines to your very doorstep. And the number of books about wine proliferates. From a culinary medicine side, wine, when properly dosed, is a healthy drink. There is really good evidence that between seven and 14 glasses a week decreases your risk of dementia. But there’s a toxic range, which is more than two glasses a day for men or one for women. Sorry, ladies.

Terry Simpson: I have enjoyed discovering new wine varietals, whether it be the long-forgotten grapes of Greece or the varieties that you see in new vineyards in Croatia. But many consider the expert of wine to be the Sommelier who’s undergone extensive training in the field, so I was pretty amazed when this Sommelier knew about the soil of these grand wines from Burgundy.

Alex Maltman: Well, he would know the soil. It’s the hot topic of the moment, particularly among Sommeliers, to be able to know the vineyard geology, whether the vines are growing in granite soil or limestone soils or whatever. They never actually say how these soils affect the vines, let alone the wines, but it sounds good, you know?

Terry Simpson: Then there is terrior. The definition of terroir is that complete natural environment in which a particular wine is produced, including things like soil, topography, and maybe especially climate. Do you taste that, or does there terroir influence the taste? I mean, can you taste dirt? Can you taste the rocky terrain on the north side of the hill? Can you taste the relative humidity or aridness in which the grapes grew? So when a Sommelier talks about wine, they talk about terroir.

Alex Maltman: And that’s fine. I don’t have a problem with terroir, the idea that any crop is going to be dependent on the site in which it’s growing. Every gardener knows that certain plants do better in certain spots in the garden than others, depending on various conditions. So the idea that vines do better here than there, that’s great. And the quality of the grapes, and ultimately the wine, is going to depend on the place? Yeah.

Terry Simpson: Soil, sunlight, water, all of those affect any crop. They will affect how much it grows, if it grows. In the case of wine, it’ll affect how much the grape will ripen and the sugar content of the grape. So how do you determine which is the most important factor? What part of the terroir is the key to how that wine is tasting? It isn’t easy, and it isn’t easy because there are a lot of myths. So what is important?

Alex Maltman: We don’t understand it. Lots of factors are involved and their importance is going to vary from day to day, season to season, year to year. And at one place, a certain factor may be important than another, whereas in another spot it’s the other way around, and it’s going to change through time with different years. So I see a sort of dynamic matrix of different, mainly physical factors to do with climate, the soil to some extent, maybe even the microbiology in the soil and in the air; these various factors constantly evolving and changing, and they all come together to make terroir. But to distill it down to a single word or a single factor is, I think, misleading.

Terry Simpson: Read any wine magazine and they’ll rank wines, and they’ll tell you what was a good year or a bad year for this or that. Most often, it was climate that made a difference. A lot of rain and the grape just didn’t get the usual sugar content; too much sun and the wine starts tasting like raisins. The soil is ever changing though, so the soil that those monks tasted centuries ago isn’t the same soil you would taste now. Not that you’d eat dirt. I mean … well, some would. Ask any parent. Recently on Twitter, a person insisted that they could take the chalk from the soil in the Champagne region. So Dr. Maltman, can you taste the soil? Was she right?

Alex Maltman: No, you can’t taste the soil. The great relevance of the vineyard ground, the soil and perhaps the stones in it if they’re there, is on the water supply to the vine because how well drained the soils are, how they store some water for times of need in arid seasons influences a lot how the grapes swell and ripen, and then ultimately, indirectly the character of the wine. This is the big contribution of the soil, the water supply, so the vineyard ground is very relevant in that respect.

Alex Maltman: And one or two others, too, ultimately provides the mineral nutrients for the vine to grow, only required in tiny quantities, but really it’s the climate via photosynthesis that decides which organic molecules are going to be produced in the grape, what we call flavor precursors. And then on fermentation, how they’re going to be transformed into the hundreds of aromatic, highly aromatic organic molecules that make a wine taste like it does.

Terry Simpson: But people insist, insist they can taste the soil. They swear to you they can taste the minerals. And because so many Sommeliers say that they can say them, they must be right, right? That’s the logical fallacy of what we call argumentum ad populum, for those of you who like Latin, or if so many people believe it, it must be true. It’s also a little bit of a logical fallacy of an appeal to authority, which means we have to believe these wine Sommeliers because they’re the educated ones, right?

Terry Simpson: Oh, by the way, to become a Sommelier, it involves a lot of tasting of wine and some knowledge of those wine producing regions. But what about geology? Other than knowing that the ‘grand’ was — now I’m sounding like Dr. Maltman — the ground was granite or volcanic or filled with chalk, they really don’t learn advanced geology or really any science. So let’s ask our distinguished professor of geology, Alex, can you taste the minerals in the soil?

Alex Maltman: No. The minerals, the geological minerals in the soil, A, have no taste. The odd exception is salt. Sodium chloride’s the obvious one, but there’s not much of that in vineyards anyway. Most of the geological minerals that make the ‘grand’-

Terry Simpson: So again, if you don’t get that Welsh accent, when he says ‘grand’ he really means ‘ground’.

Alex Maltman: Most of the geological minerals the that make the ground have no taste, no smell, and the vine can’t take those complex molecules up anyway. The mineral nutrients the vine takes up are single elements dissolved; calcium, iron magnesium dissolved in solution in tiny quantities, again without any taste. And so while they play their pivotal role in the vine growing, and perhaps then from seeing which organic molecules are produced, you can’t taste them. So no way can you taste the soil in the wine. The soil basically doesn’t taste.

Terry Simpson: So what you’re tasting in wine is not the soil, but the many compounds that the plant makes, the vine. Those are things like flavonoids, phenolic compounds, non-flavonoids, phylos, terpenes; they all provide the scent of the wine that makes up what you taste. And many of those bioactive compounds that both make wine taste amazing and make it almost medicinal, the important part of that Mediterranean diet.

Terry Simpson: So what the Benedictine monks didn’t know 1300 years ago was that the carbon that makes up those organic molecules doesn’t come from the soil. It comes from the air. It’s carbon dioxide. And the plant, through photosynthesis, takes those carbon molecules and makes the complex sugars and proteins, and it uses its plant DNA to determine the enzymes to make up the compounds that give you that delicious taste.

Terry Simpson: They didn’t know about genetic programming in the grape. They didn’t even know about genetics. But what they did know was when they smelled that humus from the soil — those organic compounds of the soil, not the minerals — that they smelled something like the wine, and that’s because some of those compounds were the same. But the plant doesn’t take up those compounds any more than when you eat a cow your muscles become cow muscle. Your body breaks it all down and rebuilds it. The plant breaks all those compounds down and rebuilds itself. So it isn’t the year 700, and what you can taste is …

Alex Maltman: If it has a taste, it’s organic molecules in the soil that you taste and smell. The favorite things like wet stones and so on, this is organic material being relativized after a shower of rain, or on a hot, sunny day. These inorganic, largely silicate compounds, sometimes carbon compounds, make the ground … They’re tasteless and the vine can’t take them up, so that’s why you can’t taste the soil in the wine.

Terry Simpson: So why do people insist that what they’re tasting is soil?

Alex Maltman: But of course, this whole business of the soil, it sounds good. It builds on the historic tradition of wine being particularly linked to the ground. That goes back centuries. And even after the discovery of photosynthesis — that the vines and plants really work by sunlight and carbon dioxide and water, nothing else — this idea of the soil has persisted. And now today, with our wish to know where our food is coming from, and drinks, and the interesting provenance and … Well, the idea that the stuff in your wine glass is linked to the soil, it chimes directly with modern yearning for an almost primeval connection with the land, with the ground, so it builds on that.

Alex Maltman: Your Sommelier’s saying about the soils, or the wine label’s saying this wine was produced on granite soils, it sounds good and it makes this link which people treasure today because so much food is anonymous, highly processed, people don’t know where it came from. So this idea that your wine is from this soil, well, that sounds good. But unfortunately, scientifically, as I’ve indicated the links are very indirect and complex.

Terry Simpson: But again, what is more important than any rock type for wine is what we call the humus.

Alex Maltman: We often forget in this geology business the importance of the small, organic fraction in the soil, the rotted vegetations on the so-called humus in practice year on year and then the agricultural situation. A lot of the nutrition is coming not from the minerals or from the inorganic part of the soil, but from the humus and certainly the nitrogen, which is the big one in plants growing. That’s got to come from the humus because geological minerals don’t have nitrogen. So wine writers like to enthuse about limestone and granite and slate and who knows what, but they overlook the fact that, in fact, most of the nutrition is coming from that 5% that’s of the soil that’s humus, that’s rotted vegetation and little creatures.

Terry Simpson: Wine making used to be a secret. It used to be as guarded a secret as any that you can imagine, like how you make up Coca-Cola. But now, wine making is open source. You can get a degree in wine making from the University of California. In fact, I kind of think I missed my calling.

Terry Simpson: You can read journals and they will tell you the best way to plant the vines, the best way to take care of the crops, you use science today for when to harvest. And as climate is changing, wine making is open to new places. Even when we visited Estonia, we noticed that they’re starting to make Pinot Noirs. Estonia. I mean, that’s like ‘winter is coming’; that’s the north wall.

Alex Maltman: The other big thing that’s happening in line with this is better know-how, science if you like. Those people in Estonia as elsewhere will know the best kinds of cultivars to plant; how best to train them, trellis them; how best to make the wine. They increased technological know-how. More and more growers are going to university to do a course in viniculture or oenology, and so the whole wine making force is better educated, and that’s making a big difference. And so far, that’s the big reason I think why wines in general have improved so much in consistent quality; not so much because of climate change yet, but because of better know-how.

Alex Maltman: I think the so-called new world, California and Australia and places, they’ve changed these attitudes. Yeah, years back — dare I say it, particularly in France — it was a closed shop. And if you wanted to visit a winery, a chateau, it was like trying to get into Fort Knox. Well, that’s all changed there now, having to open their doors and attract visitors into them. The whole way of doing these things has changed a lot. And yeah, I think largely because of American attitudes and approaches to wine making, and making it open, and making it an event to visit a vineyard and perhaps go to a concert or view some art or something, why it sure didn’t use to be like that. It’s changed.

Terry Simpson: Organic molecules, that’s what makes up the taste in wine, and it is indirectly that we have some of those components. There’s a few inorganic things you can taste. You can taste a little bit of salt and you can taste a bit of zinc, but our geology professor was pretty clear about what you can taste and what you cannot.

Alex Maltman: The soil will be just one part of that, and I don’t think the preeminent part such that wine labels and many wine writings would have it. The invisible things like climate are at least as important, more so really. You won’t be able to taste the soil. Its the effects are indirect via the water, via some of these tiny amounts of zinc and iron that the vine has to take up. Some make their way through to the finished wine, and while you can’t taste them, they do have an indirect effect on how we perceive taste, what we do taste.

Alex Maltman: We’re tasting the organic molecules, but how we sense them can be affected by slight variations of the presence of zinc; tiny parts per million or something, but it’s shown that they do have this very indirect effect. So the soil is part of the story, but it’s complex, it’s indirect, and it’s not tasting the soil in the glass, unfortunately. As a geologist, I wish I could say all of geology’s incredibly, directly important, but the evidence now leads me to say that we’d better think about the temperature, the sunlight, the humidity, the air flow, and all these things as well. Not as sexy, doesn’t make as good a journalistic copy, but in fact they are the things that are doing the business on these organic molecules that do make the wine taste.

Terry Simpson: If you’ve spent the last few years trying this new Cab, or that new Merlot, or this Pinot Noir, you might consider looking at a different variety. Wine is from the Mediterranean, but most of the time we have lost in wine biodiversity. Most of the grapes that you drink from wine are from about four different plants. So I want you to consider Greece.

Terry Simpson: Under the Ottoman influence for over 400 years, Greece is where they made wine. But during that 400 years, they couldn’t export wine. They could only grow wine for themselves. But in 1830 they became independent, and the wine varieties that you can find in Greece haven’t been seen by most of the world for over 400 years.

Alex Maltman: Another big interest now is indigenous grape varieties because the whole world is awash with half a dozen well-known grape varieties, Cabernet Sauvignon and Chardonnay. Those countries, particularly European countries, particularly eastern European countries where the grape probably first originated, they are suddenly finding they’ve got these long-forgotten particular varietals, so they’re now getting an interest and individuality, which is something else that people are seeking; not just the mother Chardonnay, but some long-forgotten variety. And there are hundreds around in some of these countries, Portugal for example. Italy has a lot, but suddenly some of the eastern European …

Alex Maltman: I’ve just come back from Hungary and they have got a whole battery of unique varietals. So if the world is trying to get away from uniform, or the interested wine drinker is trying to get away from uniformity, well, this is another route. Seek out these ancient indigenous cultivars, the grape varietal’s on the label.

Terry Simpson: Wine is a wonderful and ancient drink. Archeologists have uncovered … So far, the oldest winery that they found is in Armenia from 4100 B.C. That’s 6,000 years ago. That’s a thousand years before the pharaohs, and they drank wine.

Terry Simpson: Wine spread throughout the world and has been a part of humanity. Thankfully, every time they conquered something, they brought their civilization, and that included wine, bringing the vines. And while in ancient times the monks and others didn’t know about photosynthesis, DNA, complex molecules, they had a simplistic way of explaining taste and flavor, but now we know better. So when the Sommelier tells you he tastes soil, just smile and see if you like the wine. There are a lot better things to do than think about inorganic compounds. But don’t forget to try the varieties of wine you’ve never heard of. They’re not only delicious but they’re pretty inexpensive.

Terry Simpson: A great wine maker once said that it cost about seven bucks to produce a great bottle of wine, and that includes the cost of the bottle and the cork. Everything else you’re paying for is what’s on the label. The best wine we had on our travels this year was from Greece, where there was this old, weathered man who I’m sure was a hundred years old, and he filled up a jug from the wine in his vineyard. And his vineyard had probably been planted thousands of years ago, and the grape that was there nobody could identify. He charged me a buck for that liter of wine and it was delicious.

Terry Simpson: When we were in Mexico, the restaurants there were charging hundreds of dollars for bottles of Napa wine which you could probably buy in the States for about 70 bucks. Maybe that’s the result of those tariffs. But not wanting to overspend vacation money on U.S. wines while we were in a foreign country, we tried the Tempranillos from Mexico. They were pretty inexpensive, but they tasted familiar. And then we learned that these wines came from the Rioja Valley, originally in Spain. Turns out these vines were planted by the second sons, who didn’t inherit the vineyard. The first son always inherited the vineyard. But for some of these kids, the second son grew up loving wine with great knowledge about wine making, the craft, so their father would buy them land in the New World and send them off with cuttings and their family’s secret knowledge about how to make the wine their way. These wines were grown and produced in Mexico, and they tasted even better than those very expensive Napa wines. So if you find yourself in a country that produces wines, try a new variety.

Terry Simpson: And now, some of the con. Today, there are people taking the bioactive components of wine like resveratrol and trying to purify it. You may have heard that resveratrol is a potent antioxidant in wine, and it is. So when these cons are trying to purify it, they’re trying to sell it as a supplement that can cure a wide variety of ailments. One local group has combined resveratrol with HCG, which is a hormone found in pregnant women, and they charge people hundreds of dollars a month claiming it will help them lose weight. There is no evidence it does, and the only weight they’re losing is from their wallet.

Terry Simpson: There’s another group that has taken resveratrol and put it in with a whole bunch of other compounds, claiming people can live to be hundreds of years old by taking this. Can you imagine that? As with many supplement makers, they’re trying to con you into paying for something that has little or no science, and certainly no trials behind it. As of yet, we don’t know the combination of compounds that provide the best part of wine. So I say enjoy your glass or two, and cheers. Or as my people say, skol.

Terry Simpson: Special thanks to Alex Maltman for lending his comments to today’s show. You can purchase Alex’s book, which is called ‘Vines, Rocks and Soils: The Wine Maker’s Guide to Geology‘ wherever you buy your books, and we’ll have a link on our website. And of course, thanks to you for listening to this episode of Culinary Medicine with me, Dr. Terry Simpson.  While I’m a doctor, I’m not your doctor, and you should always seek the advice of a trusted, licensed medical provider with experience in your particular condition or concern before taking any actions. Of course, if you are my patient then what I say should be burned in the fleshy tables of your heart.

Terry Simpson: Culinary Medicine is a part of Your Doctors Orders network, and is produced and distributed by Simpler Media. My executive producer is the talented and beautiful Producer Girl of Producer Girl Productions. You can follow me on Twitter, where I am @drterrysimpson; that’s D-R Terry Simpson, and I’ll be back next week with another conversation about food, and maybe bust a con or two. Until next time, don’t drink the water. Drink the wine.