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The Science of Good Taste -- Geology, Wine and Food

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Larry Meinert: Since this is going to be a science talk, let's start with a little thought experiment.

Imagine two vineyards right next to each other. One, over hundreds of years, has produced acclaimed wine that everybody loves, and sells for ridiculous prices, hundreds of dollars a bottle. Then you crawl over a fence to the vineyard right next to it. Might be owned by the same person, maybe growing the same grapes. Everything's identical the same sun, same rain, same wind except this produces really mediocre wine that sells to the local café for 50 cents a liter.

Here's the scientific question: Why? So I spend a fair bit of time working on this question. Yes indeed, it does require laboratory experience to evaluate this properly. We tried to have a lab part of tonight's lecture, but apparently that's not so easy to do in a federal facility, so you'll have to go home and do the laboratory part as a self study tonight after the lecture.

So I'm going to be addressing this question of "why?" There's actually a technical name for that called "terroir," which is a French word that's kind of hard to translate.


[banging sounds]

Audience Member: [indecipherable 01:51]

Larry: So while they're trying to figure that out, let me continue the explanation. "Terroir" is a French word that refers to all of the factors that affect the growing characteristics of grapes. The simplest list of all the things we look at: climate, soil, geology, culture, all the things that influence the quality of wine.

And what makes this really different from normal food and gardening? Do we have anybody here who has a garden, who likes to garden? So if you're growing anything tomatoes, cantaloupe, corn you are probably going to get very rich soil and water and just baby those plants and try to get them to be as big and as luscious as possible. Grapes for wine production are almost exactly the opposite.

Left to their own devices, the grapes will overproduce. They'll produce really large grapes if they have unlimited access to water and nutrients. And they'll be just like those strawberries that you buy at your local supermarket. They're big, they're luscious, they look great.

They just lack one characteristic, that thing called taste. So if you bought those big strawberries, you always bring them home. I fall for it every time, especially after a nice, long winter. I see those luscious strawberries. I go, "Wow! Those look so good!" I bring them home, and I taste them. There's just no taste there.

The same thing will happen with grapes. And for making fine wine, you really want to get the intense flavors. And to do that, you need to restrict the vigor of the vines. So the take home message about terroir is that all of the work we do about siting vineyards and babying these plants into making a wonderful wine is controlling this natural vigor.

And if you're growing the grapes in a climate, on soils, bedrock and any of the other characteristics I'm going to describe that naturally help reduce that vigor, then nature is acting as your friend instead of fighting you. So that's a very simple explanation of what we're going to look at.

I'm going to illustrate this by looking at wines produced in three different parts of the world Washington state, California, and two regions in France -- Bordeaux and Burgundy. Starting with Washington, we'll look at four factors.

If you look at this list, you'll say, "OK. Climate? I get that. Soils? That makes sense. Volcanoes and glaciers? I don't see any volcanoes and glaciers in my wine." And so I have to explain why this is so important, why it directly relates to the quality of the wine.

Let's start at the top with climate. On the left is how the world views the climate of Washington state. If you think about Seattle or the Olympic rainforest, that is indeed what it looks like. But on the right is what it's actually like where the grapes are grown, where the vineyards are situated.

And the reason for that huge difference between those two images or parts of the state of Washington is easily visible on this map if you're trained to read maps. That is, we have a mountain range, the Cascades, running north/south right through here. And these are fairly tall mountains. The one that's probably most familiar to people is Mt. Rainier. If you fly into Seattle on a clear day, which isn't all that often, you'll fly right next to it.

These mountains form a very effective rain shadow. When people hear that word, they tend to think that this is a physical barrier. And the moist clouds coming off the Pacific just sort of run into that and stop. They can't make it past it. That's not what happens at all.

This is simple physics. The air rises up over the top of the mountain. As it the air rises, it cools. Anybody who's been hiking in the high country knows that it gets cooler as you go up. And as it gets cooler, the air can hold less moisture, so it rains. It drops the moisture out.

Then when the air goes over the top and back down, this process reverses. Now the air warms up, but it's already dropped all of its available moisture when it was going up. So now the air is sinking. It's getting warmer. It can hold more moisture than it has.

So there are places to the east of the Cascades that not only are true deserts, there's places with negative evapotranspiration, negative rainfall. It doesn't rain. It actually sucks up moisture from the ground as these hot winds come down. That's why we have this zone in the middle of the state that forms in the rain shadow behind the Cascades. This is one of the critical elements for producing fine wines, being able to control the moisture availability to the grapes.

The other thing that happens with these big mountains is that they are stratovolcanoes, and periodically they do this. This is Mt. St. Helens in 1980, erupting. And so they're spewing huge amounts of ash into the air that then can fall back down on the landscape. So this is a part. Turns out not to be a large part in Washington.

These eruptions are quite large. The ash column will go up vertically until it achieves neutral buoyancy. It will be swept along by the jet stream. And a really large eruption in about two weeks will entirely circle the globe. And that's interesting because we have this ash raining out. It's a very small amount. That means that every place in the globe has got a little bit of ash from these volcanoes.

Next time you're visiting a fine vineyard in France telling you that it's a wonderful, wonderful wine, you can say, "I taste something in this wine. It's very familiar to me. It's Washington State!" If you know anything about French culture you know that, "Ooh, that knife went in, and it's being twisted." I don't mean to imply that it actually has any effect whatsoever on the taste of the wine, but it is factually true that volcanic ash from these things is very widespread all over the globe.

The other thing that a trained geologist would see from this map is the effect of glaciers. For those of you who haven't spent your whole life studying maps, I'll show you what that is. This is what the world looked like 15,000 years ago. Glacial maximum. All of Canada was covered by a very large mass of ice. And there were lobes that came down across the present Canada/US border into the Great Lakes area.

If anybody is from New York City, Long Island is the terminal moraine from one of those big ice sheets. The ice came down, it melted, and it dumped out material, forming Long Island.

Washington State's ice came down into Puget Sound into this area. If you look a little bit more closely, you can see a big lobe of ice coming in here, lots of lobes of ice.

And the glaciers are important for two reasons. One, these can transport a huge amount of material. So if we go to a modern region this is up in Alaska we can see glaciers coming down the valleys. You can see all the dark material on top of that. That's rock, debris that has cascaded down the slopes of the mountains onto the top of the glacier. They're being transported.

If we go down to the surface of the glacier, you can see large rocks like this. This is what geologists do for fun, ride these galloping glaciers. They actually move pretty slowly. It's not that difficult.

But what's important about this is that is a very large chunk of rock. The only thing that can move big chunks of rock like that is glacial ice. Wind can't move it. A river's not going to be able to move a block that big. So, when we find these big blocks dumped out onto the ground, even if there's no longer any ice there, it allows us to interpret that there was ice.

So this is the essence of geological reasoning, of understanding how the processes work to be able to make an observation that if I go into a vineyard or behind a Wal Mart and I see a big block of rock like that, I know that the only process that could have gotten that rock there is glacial activity.

The other thing that's really important about these glaciers is they came down from Canada and they blocked up lots of rivers, lots of different drainages in here. This is an artistic rendition of what it was like.

The one that's probably most important. A lobe of this glacial ice blocked what is the present day Clark Fork River in Montana, and it formed a lake behind this big tongue of ice that covered the western half of Montana to a depth of about 1,000 feet. So this is a huge lake. If you're flying to Missoula, you'll actually see the old beach lines up there on the mountain walls around Missoula.

And just forming a lake by itself wouldn't be of tremendous importance, except for one little thing. As that lake got deeper and deeper and deeper, held in by this ice dam, this lobe of ice, more physics. Ice? Water? Ice floats on water!

Eventually when that water got deep enough it caused the catastrophic failure of that ice dam so that this huge body of water again, covering the western half of Montana suddenly raced across the state of Washington and drained out. That's what's being illustrated here, artistically. So it raced across the state of Washington out the channel of the present day Columbia River, back flooded the Willamette Valley down in Oregon, and swooshed out into the Pacific.

The amount of water that flooded across the state of Washington and we can calculate that it took somewhere between a week and two weeks for that water to drain across the state is more than 10 times all the world's rivers at flood stage simultaneously.

Take the Amazon, take the Nile, take the Mississippi, all the world's rivers, multiply it by 10, that's how much water was racing across the state of Washington. That water was going very fast, and it had a tremendous impact on the landscape.

We can see this pretty easily with either airplanes or flying over in a satellite. You can see what looked like river channels here. These are farm fields. This is a satellite image and this is where the water was flowing. There’s no rivers in this thing now. This was a very short lived again, one to two week burst of water flooding across the state of Washington somewhere around 15,000 years ago.

It carved through all of the soil that used to be there. This water is flowing fast enough it actually carved its way through the bedrock as well, channeling right through it. If we go down to ground level we can see one of these.

So this dry valley in here, this has a geologic name called a coulee, and you've probably heard of the biggest one of these in the United States. That's Grand Coulee, and the engineers used this natural occurrence of this valley to build Grand Coulee Dam, and then they did what Ma Nature did. They filled it up full of water behind the dam.

That's a farm down there. There's a road. This is a fairly wide valley, and there's no river in there. This is very unusual. Normally when you have a valley and you have these steep walls on both sides you'd be seeing some sort of creek or river flowing down the middle. But there's not, because this, as I go back, is one of these little channels where the water is flowing across the state.

Now why is this important? Because that water got rid of the soil that used to be there, stripped off a lot of things, mixed this all up, and I'll show you what it did with it. This is another artistic rendition of what that flood would have looked like so you can see big chunks of ice coming down along with it. It's going over a series of breaks in the rocks forming large waterfalls, but there's no water there anymore.

So imagine that you went to Niagara Falls or Iguaçu down in South America. Somebody just turned off the water, and you're looking at Niagara Falls without any water. You'd have this big dry waterfall. Well, that's what this is. There's no water there right now. It's called Dry Falls State Park in Washington State, and it looks just like Niagara Falls without the water.

And all these things were a real mystery to people for a long time. They just couldn't understand how could this have happened? And somebody actually put forth a very clear explanation of how this happened. It was J. Harlen Bretz, and he was just heckled by all scientists, because if you can imagine, go back 100 years, and you're going to invoke a large flood. It has certain rings of science that we tend not to go there anymore.

Some other features from this huge flood...these are giant ripple marks. Again, for scale, here's a four lane highway in the background. These ripple marks are just like the ripple marks you would see on the beach or the side of a lake causing by water moving back and forth, except these ripple marks have crests that are 100 feet high and are one to two miles long.

That's because the water was moving so fast that it formed these huge features that on the ground you can't even recognize them. They're just hills. When you get up in an airplane you see that these are in fact ripple marks, and we can calculate how fast that water was moving, roughly about 100 miles an hour. So if you were there when that flood occurred, all you can do is wax up your surfboard and get ready, because you're not going to outrun it.

All that water is rushing across the state, and it eventually went through the modern day channel, the Columbia River, and it went through several constrictions, several places where the canyon walls narrowed, and this the most famous one. It's called Wallula Gap, and these cliffs are between 500 and 800 feet high. This is the modern day Columbia River flowing through it.

So all that water was trying to go through this constriction. It was like having a kink in your garden hose. It caused the water to back up behind this. OK, now, there was no physical barrier. This was just more water was coming through than could go through that valley, and what happened is that, here's Wallula Gap down here, so the water was rushing across the state in this direction.

It back flooded the Yakima Valley, the Walla Walla Valley, and all this stuff here in the Columbia Valley, so all this blue speckled, that's water. It caused that water to back up, and it took, again, between one and two weeks for all that water to drain out.

So think about this water. It's racing across the state of Washington at 100 miles an hour. It's picking up everything in its path so it's ripping up the soil. It's ripping up rocks, cows, trees, you name it, Toyotas -- whatever was out there, it's all getting swept along. Now it's ponding up behind here, temporarily, only for a couple days, a week at most.

The water now is not moving 100 miles an hour anymore. It's still for a few days. And all those things that are being carried by the water, they're all going to get dumped out. So where this water is, where it's shown temporarily as a lake, again just for a few days, is now a deposit of all the mud and all the stuff that was being carried along by this flood.

And I want you to memorize this map, because the next map I'm going to show you is where all the vineyards are and there's a one to one correlation. More than 95 percent of all vineyards in Washington State are on these flood deposits.

That's why when I listed those four things, climate's important. If this was Greenland we wouldn't be growing wonderful vineyards. But this glacial history is essential for why Washington State wines have the characteristics they do.

So what is actually happening in these valleys that are being back flooded? When the water slows down it's depositing mud, and this is a spectacular location. We can actually see what happened. Most of the Walla Walla if I go back to this the Walla Walla Valley is this little valley down here. All this mud was just deposited as flat layers. It's like on the bottom of a bathtub.

This ditch or canyon cutting through it actually formed in one weekend when an irrigation ditch...somebody forgot to turn it off when they went home on Friday, and it overflowed, and it cut through this. This mud is like a knife cutting through butter. When they came back on Monday they went, "Oopsie," and that irrigation ditch cut to this canyon.

If you can't see it there's a person up there for scale. Most of Walla Walla is nice flat mud layers like up on top. Without this canyon we wouldn't be able to see it. We know it's there geologically. We wouldn't be able to see it. But in this one location you can actually see it, and each one of these mud layers is the result of one of these big floods.

Now for those of you who are grammatically astute, you're saying, "Wait a second. He said floods. Now looking at that I see lots of these layers. I might be willing to believe him if there was this one big flood, but now he's asking us to believe that there were dozens of these floods. Maybe he had the wine before he started this lecture...


Larry: ...and he doesn't quite have it right.”

What's actually happening? How did this form? The big ice lobe came down from Canada, blocked the Clark Fork River. The water backed up slowly over a period of 100 to 200 years forming this huge lake covering the western half of Montana until it was more than 1,000 feet deep. It got deep enough that it eventually floated and broke up the ice dam.

The water raced across the state of Washington, took a week or so to get out to the Pacific, and then what happened? The glacier ice slowly flowed back there, blocked up the Clark Fork River again. The water started rising. That whole cycle takes anywhere between 150 and 200 years to repeat.

Each one of those layers is the result of one of these flood cycles. So as long as that big ice sheet was covering Canada this is kind of a predictable and unavoidable consequence, and for the geologists in the crowd, you've probably observed that those layers are thickest down here, and they're getting a little bit thinner.

They're still pretty big. These are multi meter thick layers of mud. That's because the first one that went through ripped up all the mud that was there, and then the second flood went through that same channel and so it was ripping up mud from the sidewalls of that, and so each one had less and less stuff they could pick up as it was flooding through there.

So what happened after the flood? The water moved through. It dropped all this mud. The water is gone. The sun comes out. The whole state is covered by this meter, couple of meters, wet mud. It dries out. The wind picks up, and now you have hellacious dust storms. This stuff is just loose mud all over half the state.

The wind picks it up and starts blowing it all over the place forming huge sheets of sand dunes. So that material ends up on top. These fine layers in here, that's what's deposited by the floods. These are what we call the slack water sediments. When the water slows down it drops out the mud.

The sun comes out. The wind starts blowing. This material up on top is basically a big sand dune, and it's a sheet of sand that covers most of the state. There's another geological term...loess is the name for a sheet of sand that covers a very, very large area. It's not just one single sand dune.

This package of material from the windblown sand on top, the loess, that is windblown reworking of this stuff, which is the mud deposited from these floods, and that stuff is all the soil and rocks that were covering the landscape that got ripped up by the water. This is the substrate for almost all the vineyards in Washington State.

Some of them have more of the sand. Some of them have more of the slack water sediments. Some of this is so deep that the roots never get down to bedrock. It's just growing in this. So why is this important? Why am I spending 15 minutes of my precious time not talking about the wine yet we'll get there, trust me but about all this geology stuff?

Because, remember we started off it's controlling the vigor of the vines. So this is the media that the vines are growing in. Let's think about what this stuff is. How much organic material is in this? Pretty close to zero.

A normal soil horizon develops, let's say in Kansas over hundreds of thousands or millions or tens of millions of years, develops a very organic rich part, which is why that's a great place for normal crops, why you can grow soybeans and corn and everything else in Iowa and Kansas, because those are much older soils.

This stuff was all deposited within the last 15,000 years, and it was deposited by all this water reworking it, stripping out any organic material that was there. So if there were decaying leaves, whoosh, that's all been taken away by the water. This is about as sterile, as un nutritious stuff as you can find, and it's very well sorted grains of what we call sand or silt, so that when there is water it drains right through it.

This material has very low nutrients, and it has very low water holding capacity. It drains the water out. If your goal is to control the vigor of the vines, this is the best vigor controlling stuff highly technical term you can imagine. That, in a nutshell, is why this is really good.

So, your photographic memory now comes into play. This is a map of the appellations. The technical term is the AVA, America Viticulture Area, and there's several of them, the Yakima Valley here, the Walla Walla Valley down here, this larger area of Columbia Valley. These are the legally defined areas where the grapes are grown.

And you can probably visualize that this Columbia Valley is exactly the same area where all those slack water sediments were deposited, where all those lakes were clotted up behind Wallula Gap. It is literally true that the vast majority of all Washington vineyards are growing on this glacially deposited stuff, and it's not an accident for why that's so good for the wines.

And if you think about this in real estate terms location, location, location imagine that you have a vineyard here producing really, really good wine versus a vineyard over there, which is probably going to be incapable of producing commercial wine at all.

When I was a professor at Washington State, which was over here in Pullman, I would get calls, because I would publish things about this research. I'd get calls every week from a farmer saying, "You know, my neighbor has put in a vineyard, and he's getting $1,000 a ton for his stuff, and I'm selling my wheat for $5 dollars a bushel, and it's just not quite the same. So can I plant these grapes and do as well as he's doing?"

I said, "Well, where are you located?" You can imagine this coming over the telephone, "Well, my neighbor's vineyard is right there, and here's my farm over there." I'd say, "Well, no, yours actually would be really terrible."

"What do you mean it's really terrible? I'm right next to this guy who's getting thousands of dollars for his stuff. What's wrong with you? Are you an idiot?" I'd say, "No, I'm a geologist. That's a special kind of idiot."


Larry: So this is why it's so important understanding why this has the effect it does, and then eventually we'll get to how it affects the actual taste and quality of the wine. So we're going to look at the Walla Walla area. Let's go back to that and point it out. So Walla Walla is one of these little sub valleys that was back flooded by the big floods.

What's being shown on this map, this is the appellation boundary. See this black line sort of curls around here, and that's the limit of the legally defined Walla Walla Valley, and this is a map showing different soil and rock units. They all have different colors. These little black squares you can see here, those are individual vineyards.

Here is another thought experiment. We could ask the question, "Do the vineyards on the brown stuff produce better or worse wine than the vineyards on the yellow stuff, or the red stuff, or the green stuff?" It's a highly technical question that we're posing, but it's pretty straightforward.

These are different soil rock units that had to do with this flood, and we're going to go look at the vineyards on those different substrates to see if the plants are different. The next step will be then to look at the wine that's produced from it, and ask whether the wine is different.

We are standing in one vineyard looking across several of those colors, so this would be the red stuff. This is what's called a slack water terrace. You can see the rows of the vines over there, and the flood plain is alluvium. That's a different color. That was the yellow stuff on that map. That terrace back there is the Pepper Bridge Vineyard, one of the most famous vineyards in Washington state, produces spectacular wine.

It is impossible to grow grapes here on the flood plain. What they grow there are onions. You may have heard of them, the Walla Walla Sweets. They're actually quite famous, and they're great onions. But onions and wine are two different things. Even though the distance from here to there is 50 feet, it's a HUGE difference in what you can grow there and the qualities of it.

This is really different than if you were growing wheat or soybeans or corn, because you're just not going to see that variability, and you're not going to see the connection between what's in the ground and what eventually goes into the produce.

Now we're up in the vineyard at Pepper Bridge. We're looking right down the row so let me give you a short primer on grape vines and how this works. So here is the trunk of the grapevine, and then the branches or they're called cordons are trained horizontally up here on these trellis wires. This entire area here, the leafy area, is called the canopy.

And this is a beautiful vineyard that's in balance. What we mean by that is the amount of leaf mass up there is in balance relative to the size of the grapevine to the root mass in terms of being able to get these grapes ripe. If you have too much canopy due to too much vigor of the vine so there's too much water and too much nutrients so the vine can produce this huge mass of leaves, you won't be able to get the grapes right.

This is somewhat like Goldilocks. You want to have just the right amount not too little, not too much and this is what a perfect vineyard looks like, and I want you to mentally photograph the amount of canopy there, so the size of the trunks as we're looking down the rows, and this grass is the middle is what they call a cover crop, and that's usually planted to the keep the weeds and other things down.

Now we're going to move about 100 feet across one of those color boundaries on the original map, so a different substrate, and we're looking right down the rows. There's an end post there. There's an end post there. These vines, their roots actually have access to water. They can tap the water table because of what they're growing on, and you can see the vigor of these, the balance or lack of balance between the canopy and the vineyards.

There's no way of getting those grapes right even though we are 100 feet away from one of the best vineyards in Washington State. This is a classic example of location, location, location. This is the actual owner of that, and he planted this vineyard right next to Pepper Bridge for all sorts of logical reasons that, "Oh, boy, I'm going to be doing great," and he quickly figured out that this dog won't hunt, that these grapes just were never ripe.

And two years after we did the studies sort of explaining why things weren't working the way he wanted, he ripped all this out and started growing barley, because he just realized that it couldn't be done, OK? I go through these examples because until you sort of see this and walk through it, it's really hard to get in your mind, "Well, there's a patch of dirt, and there's a patch of dirt, so how could they possibly be producing such different crops?"

I mean here you can see with your eyes these plants look different. We'll get into the wine thing in a second. So here's another thing you can grow on. Where the water's moving more quickly we don't get silt sized or sand sized grains. We are actually getting large cobbles so the water's moving much faster.

Here's a vineyard growing on these cobbles. In fact, they named the vineyard the Cobblestone Vineyard. Again, if you're a gardener, and you're growing tomatoes or cantaloupe, and you look at that, you go, "Oh, my god. There's just no way that I could grow anything on that."

The person who planted this vineyard is a guy called Christophe Baron, and he's a Frenchman. He's what they call a traveling winemaker. He had grown up on the family estate in France, and he traveled all over the world working harvests different places. He knew eventually he wanted to settle down someplace and have his own wine estate.

He looked at every place in the world, and he saw this area, and it all looked like this. He said...his English is quite good, but he likes to ham up his French accent. He goes, "Oh, I like this ground, because, oh, they're going to suffer here." They not only suffered here. This land was worthless. You couldn't even grow apples there, which in Washington State you can grow apples almost everywhere.

He bought this for almost 10 dollars an acre for the stuff because you just couldn't do anything with it, and he planted them. To plant the vines he went out there with a crowbar, stuck the crowbar in the ground. He'd wiggle it back and forth, and then he'd plant the bare rooted vines in there and just kind of put the gravel back around the plants.

Then he said he'd go out at night, and he'd sing to them to try to just get them to go through the first year or so to grow there. Whether the singing part's true I have no idea, but I can certainly vouch for this is pretty hungry looking ground. If you look at it, here's a cross section through it. We often dig trenches to be able to map from the surface.

You can see the roots going down through it. It's gravel all the way down. And most people looking at this would go, "Oh, it looks just horrible." This is great. For growing grapes you have to sort of retune your whole thinking mechanism.

OK, we're not growing tomatoes. We're not growing corn. We're growing grapes, and to make high quality wine we need to restrict that vigor, and so this is good. It's good because of the lack of nutrients. It's good because of the drainage characteristics of it for the plants.

Some other things we look at the air drainage, how wind and air moves around the vineyard, is critically important for avoiding frost, for changing the humidity and keeping out certain diseases. The presence of these turbines up on the hill gives you a pretty good idea that there's a fair bit of wind here, and a moderate amount of wind is a good thing. Hurricane force is not quite so good.

We can map that out, and so here is the same Walla Walla viticulture area, this outline, and these things here that look like dart boards, these are called wind roses, and they're telling us the velocity. As you go out the numbers get bigger. It's actually meters per second, so it's telling us how fast the wind is blowing and what direction it's blowing at different times of the year.

So this is measured through a period of several years so that individual vineyards, you could determine that this slope might be different than this slope because of the way the air moves around them. You're going to have to take measurements of observations, because at any one day you're just not going to know what the air drainage looks like.

The other thing on this map is to put contours for precipitation. These dashed lines going through here, this is less than 20 centimeters of rain so that's six to seven inches of rain a year. It's a desert.

There's a pretty strong gradient across this valley because we are going up in elevation. By the time we get over here we're up to about 20 inches of rain a year, which is still a lot, lot less than the East Coast, of course, but this is all well within the range of where we want good grapes.

Again, we've got these little black squares. Those are individual vineyards. So the previous map I showed you with all those colors told us about the soils and rocks that were there. Here we're integrating in the wind conditions, and the precipitation, and all that is part of this thing I call "terroir" that affects the desirability of a particular place.

We'll look at one more before we zip across the ocean to other venues, and that is this tiny little red thing here called Red Mountain. You might ask, "Well, why should we care about Red Mountain?" This one little patch of ground produces arguably the finest wines, not only in Washington State, but in most years, in the world.

So some of the Cabernets and Syrah's from this area have won every award you can win, so these are really, really special wines. Some of them are pretty pricey wines. Here's another, not quite a thought experiment, but when I was doing this research I was a professor. Professors aren't paid a huge amount so I had this horrible decision. "How am I ever going to taste these really good, really expensive wines since I can't afford to buy them? Research!"

So for the scientists in the world there is hope. We designed some research experiments where we went in there to do the same sort of documentation we did for Walla Walla Valley, and here we actually took it all the way to the step of making the wines. Of course, we had to sample those wines, and some of the wines that had to be repeated, we sampled for statistical purposes.

So you know how to do this now. You don't even need me to tell you this. I'm just going to really speed it up. Here's a geology map. We've got different colors. This black outline is the AVA, the appellation for Red Mountain, and within that we could do the thought experiment. You know different colors, different vineyards, will they have different effects?

Here is the oblique area photograph of Red Mountain, which is this ridge back here, and draped over the top of it is a color infrared aerial photograph. Color infrared has different colors and it corresponds to chlorophyll, the ability of the plant to do photosynthesis, so the bright red areas are actually living matter, and the green areas are the lack of things. It's sagebrush.

You can very clearly see the vineyards here. The same thought experiment do different vineyards on different substrates have different characteristics for the grapes and then for the wine produced from them? This area is right in the middle of Washington State. So what happened to this 15,000 years ago?

These floods I was talking about right through this area. Here is my artistic rendition of what it looked like. This is why I went into geology rather than into fine art. Here comes the water swooping around Red Mountain, and as that water continued to flow this is the high water mark.

The standing water was never over the top of Red Mountain. When the flood first came through I'm sure there was a huge standing wave over the top of this, so if you're a surfer this would have been a good place to stand. Get you surfboard waxed up and just got to catch that wave as it's going by and then get off when you get to Japan, and you're all done.

So what am I showing you here in this wonderful artistic drawing? The water is racing around this ridge right here, so we're getting a back eddy. If we got any trout fisherman you know exactly where this is going. This is slightly calmer water here, much faster water over there.

These big black dots represent big icebergs that are being carried along in the flood waters, and trapped in that ice are lots of boulders and sand and silt, and when some of those icebergs ground, when they get stuck along here at the high water mark, when this water recedes after a week or so, then those big icebergs melt out and they drop their suspended load.

Now we're on the ground looking up at Red Mountain, and you can see that there are some little things here with arrows pointing to them. Those are what we call glacial erratics. Erratics is they don't belong there. They were dumped out by this flood, and glacial because they were transported initially by glaciers in the ice.

And they may not look very big from here, but if we go up closer to them, this is what those boulders are, and there are two observations you can make as a trained geologist. One, this is a fairly rounded boulder so something had to knock all the sharp edges off that, and that was the tumbling around both in the ice and this being carried along in the iceberg.

Two, it's bright white, and it's bright white because that's a big block of marble. And there is no marble within 500 miles of this spot. We can go up into Canada and find the outcrop that that boulder came from that was transported by the glaciers in the big ice dam. The ice dam broke. The big flood raced across the state forming all the things that the vines can grow in, but leaving these boulders as evidence for the geologist saying, "This is what happened here."

So to study these things in detail we either dig trenches or we use natural exposures, so you can see the vineyard up there. Those roots are going down. Here in this cut we can see the top part right in here. It has sort of a vertical structure. That's the loess. That's that windblown sand material.

Then down below it this is all the water deposited flood material, and some of it's finer grained like in here, and there's lenses of coarser material, and that's where the water was swirling around. But to look at this in more detail...This is what geologists do. We make detailed maps of this. So we can actually map out the grain size distribution.

An individual plant, its roots are going into different sized material, and that's going to affect how that plant grows. And some of those coarser lenses of material, so the water moved faster, is where the groundwater can move more quickly through here. This is very arid climate so that water evaporates and deposits calcium carbonate...we call caliche.

This not only has a different drainage structure to it, that calcium carbonate that's deposited over hundreds or thousands of years affects the pH of the water. So here's one more effect we're looking at the mountain, water, the nutrients, and now the pH or the alkalinity of that water. That all affects how the plants are going to grow.

So here comes yet another one of these wonderful scientific thought experiments. So there's the outline of a particular vineyard, Ciel du Cheval. It's one of the most famous vineyards there. These grapes sell for thousands of dollars a ton, and by showing the different colors are these different grain size of material I just showed you in the last slide, so we can map them out.

In terms of soil series these are given different names. We don't need to worry about the names the Hezel, the Scooteney, the Warden but what you can see is that we have vines growing, planted, those vineyards right across all three of these. This is the same vineyard, the same grape varieties, the same sunshine, the same rain, the same wind, the same grower, the same management style.

Everything is identical expect for what's in the ground that these plants are growing on. So this is the first time we're doing controlled experiments of the grapes that are grown on here and then wine made from those grapes, from these different spots, asking once again a very simple question, "Are the grapes, and does the wine made from these three different substrates, taste different?"

That's a fairly simple thing to do. It's a much different question than, "Is this good wine or bad wine?" That involves some level of taste, but anybody in this room could do this A versus B and say, "Are these the same or are they different?" And we do that repeatedly, and there's a whole scientific protocol for how you do this to make it statistically valid, and some of these we have to sample over and over again.

So this is what it looks like on the ground in one of the substrates. We're looking right down the rows. These are planted on one meter spacings. They're really close together because these are really, really high quality vineyards, and this is about as close to perfect as you can get in terms of the canopy and the trunks.

You'll notice the ground cover here is brown. That's because it's very dry, so this isn't the bright green we were seeing at the other vineyard. Now we're going to move about 20 feet across one of those boundaries, the same day, and it looks like this. Now for those of you who are trained observers, which is everybody in this room or we wouldn't let you in through the door, you can see two things immediately.

One, the ground cover is green here, so somehow it's getting water, and I guarantee you they're not going out there to water this to make the grass grow. And two, the vines, the canopy, is much bigger. We actually see some of these growing together.

If you don't go through there and trim those back this will very quickly turn into a pretty dense jungle. Not nearly as bad as the one I showed you from Walla Walla, but this has a different level of vigor than the one next to it. So I was showing you on the map those different colors. This is the result in terms of what happens with the plants.

Now when I say that you want the vines to suffer, just like Goldilocks, this is too much suffering, and so now we have crossed yet another one of those boundaries to a different color, and here there's not enough water holding capacity and not enough nutrient holding capacity in terms of clays for these plants to really survive at all. This is too much suffering.

So how do we go about quantifying it? I've shown you pictures of things. I know you can see with your eyes this plant has more leaves, that one has less leaves. So when we get in there, and we're doing this technically, and in the winter all these plants are pruned back, and we can weigh the cuttings from that. That's how we can quantify the vigor of the plant. So it's not just going, "Oh, yeah, there's more leaf area over there."

We actually measure that. This gets technical in a hurry, but we average the cuttings from different samples. We repeat this over and over for a three year period so we can average out three different weather cycles so to document, and in fact these have different amounts of vigor.

Next thing we do is we look at the grapes themselves that are growing here. So now a little short seminar on grape physiology. Why do we care about what the grapes look like? Here are two different bunches grown on those two different substrates of the vineyards I was showing you, and the one on the left is a larger bunch of grapes than the one on the right, and the individual grape berries are larger on the left than on the right.

So you can see there are differences or what we can call vigor of growth in the size of the grapes. Why is that important? How does that connect to this thing we call the science of good taste? Well, if we think about an individual grape, all of the color, all of the anthocyanins are in the skin.

The grape is this thin skin. It's got juice, which is basically a sugar solution and a few seeds in there, and as the grape gets bigger and bigger, the volume of liquid, relative to the skin, which is the circumference, so those of you who are geometrically astute, it's varying as the square of the radius, the cube of the radius for the volume.

So as that grape gets bigger, the amount of skin, which would be the color and most of the flavor, the pigment, and the anthocyanins, the tannins, the things that give the wine the structure that fill your mouth, that's all concentrated in the skins. As that grape gets bigger, you'll have less and less of that.

So as the vine suffers, as we get smaller grapes on the right, the wine produced from that is going to be a more intense wine, and assuming that all the other variables we're playing with, in terms of this is a nice flavor that we like, it will be much more of that nice flavor in the one on the right than the one on the left.

And if we have a flavor that's too strong, then the one on the left will be better because it will have a less intense of that not-so-good flavor. I'm using highly technical terms, but I think you get the drift. You can taste these things. You can see differences. This is what I mean by the grapes are different from these different substrates that the plants are growing on.

But this we did beyond just looking at the grapes so then the next step is taking this into a research winery. You see the pink label on the right, the yellow label on the left. These are different batches from different things we could map in the field, and they go into the research winery.

We know it's a research winery because we're treating every single batch the same. This is why this it's a scientific experiment. And so it's the exact same yeast, the exact same temperature, fermentation. We hold everything constant.

The other way you can tell it's a research winery is that all the equipment is labeled, "Research," on the side, and that's because they're right next to a commercial winery, and anybody who's ever run a lab knows that your lab equipment’s always disappearing. You never know where it goes. Little gremlins come in the night and your lab equipment disappears, so they label everything with, "Research," in the research winery.

You can see all those different stainless steel tanks back there, and so each one of our batches can be fermented separately, made into separate wine under commercial wine making conditions.

And we can do all sorts of technical measurements of that, and I won't go into this in any detail. We can measure the pH. The TA is the titratable acidity. Brix is a fancy word for the sugar content of the grapes. These are all things that affect the quality of the wine, and particularly the balance between the acid and the sugar are critical for the quality of the wine.

So we can measure these things, and we can ask the question, "Are they the same or are they different?" for the exact same grape variety grown on these two different substrates. We can measure this. We write up in our terroir papers.

So that's all in Washington State. Now we're going to motor through. We're going to look at two other areas to see how they are different. We're going to jump down to California looking at the influence of tectonics and alluvial fans on this. This is an aerial view looking at the Bay area, and for the geologists in the crowd, I don't need to tell you what all these linear looking things are.

So this is the San Andreas Fault cutting through here and various splays of it. If we look at Napa County up there on top, there are splays of the San Andreas, the main strand of the San Andreas is coming right through here, right through there, up to Point Reyes, in through there. So these are strands of movement along the plate boundary that is the San Andreas Fault.

As we go up into Napa we can see that there are individual valleys. There's Napa Valley with fairly straight walls to the mountains. These aren't really tall mountains, not like the Cascades. We have a flat floored valley, and these are strands of the faults, subsidiary faults. So each one of these is a fault bounded valley.

Why is that important? Because the valley floor has sunk down, and the walls are going up. Erosion is occurring off those walls forming what we call alluvial fans. So now we are looking at the side of this valley. Here's the mountain and the ridge over there. It's got a creek coming down here, and it's dumping out onto the valley floor.

And there's a slight slope to this floor, and then this cutaway cartoon you can see illustrated that what is being dumped out by the creek every time it rains and water cascades across here, we get coarser material dumped out here where the water first goes to the valley floor, then it gets finer grained as we go in this direction.

Hopefully what you can see is that a vineyard here is going to be on slightly different stuff than a vineyard here. Let's imagine that you were, oh, let's say a Silicon Valley tycoon. You just made a billion dollars on your latest startup, and you decided that, "I want to be a winemaker. I want to have my own winery."

It's a dream that a lot people have, and there's a little joke in the wine industry, "The best way to make a small fortune in the wine industry is to start with a large one, and you'll pretty soon have a small one."


Larry: Assume you had the large fortune, and you go here, and you go to your real estate agent. Now it's probably going to be a real estate agent who specializes in vineyards. You say, "I've got more money than sense, and I want to buy a vineyard here." The real estate agent says, "You're in luck." Anyone who's ever dealt with real estate agents you know exactly where this is going.

"I just happen to have a really special property. In fact, our newest hire..." I wouldn't tell the story about...OK. You're out here, and you're buying this, and let's say the real estate agent says, "This vineyard right here is very famous. Say it's owned by Francis Ford Coppola, or Robert Mondavi, somebody.

"I just happen to have the vineyard right next to it. I can get it for you for a steal. Five million dollars and I can get you this vineyard. It's the size of a postage stamp, but five million dollars I can get it for you, and you'll be right next to him." And location, location, location, you think, "That's great." If you're buying a house, I'm right next to the school, or the restaurant, or wherever I want to be. I'm right next to this great vineyard.

But your eagle eye has spotted something. You go, "Wait a second. What's this red line here?" That's the outline of the alluvial fan that tells us the material in here is really different from the material on the other side of it. You point this out to the real estate agent.

You say, "Wait a second. I went to a geology lecture, and this is an alluvial fan, and that property you're trying to sell me is on the other side of the alluvial fan." The agent's eyes get really big, and looks at you and says, "Oh, El Diablo, go away." Real estate agents don't like it when you know more about it than they do.

So the point of this is what it's growing on makes a really big difference, and if we take away the geology, and you're just looking at this, there are vineyards, and there are vineyards. They're all in Napa Valley, very famous place, and you say, "Oh, that's great. I have a vineyard in Napa Valley."

So there are really big differences on the scale of terroir that hopefully you can now see and begin to understand.

There's a lot of people who've gone there into Napa Valley. This is probably one of the most famous. This is the joint venture between the Mondavi family, arguably the most famous wine producing family in the United States and the Rothschild family from France, certainly one of the more famous and richer families of France. They got together to make a winery to produce one wine, Opus One, which sells for very, very high prices. They did everything the very best they could.

So here they are. Price is no object. They're going to Napa and they're saying, "I want the very best place." Where do they locate their Opus One vineyard? Right there on the fan. There's the apex of the fan, and they put it right there. What's going to be there?

OK? This is the closest part of the fan to where the headwaters come out of the mountain, so it's going to be the coarsest material. It's going to have the best drainage and the fewest finds, the organic material for the nutrients. They put this right in the right place, because they were French. They knew about this terroir stuff. It's a French word.

Here's another one. This is the Stag's Leap Vineyard. I show you this one for one simple reason. You've probably heard either about the movie "Mondovino" or the famous tasting that occurred in 1970's in France. This was a watershed moment no pun intended in the wine world, because to make a long story short, we had a series of wines from different places around the world. All the judges were French wine writers, vintner winemakers, restaurant owners; all the judges were French.

It was a blind tasting. They did this. At the end of the day, two wines from California won. This was transformative, because up until that point, even though lots of people knew better, it was a common knowledge that, well, you can produce wine in lots of different places, but really the only good wine is there in France.

And so when this happens at a blind tasting and you can't say, "Well, you know, it was the American judges. They didn't know what they were doing." So it was the French judging their very best wines against that and so the Cabernet sauvignon that won that came from Stag's Leap.

Just like I went to Red Mountain, why would I want to go study this? Well, this is the most famous wine in the world. If you go there, and you look at it very closely, this is what's happening alluvial fan. So these are different vineyards within Stag's Leap. This is where the drainage is coming down from the mountain. These are individual debris flows that we can map out in the alluvial fan within this broader thing, the alluvial fan.

If we dig our little trenches there, just back hoe trenches into the vineyard, and you have to have pretty established research to go and convince somebody to let you dig up their vineyard with a back hoe. Trust me. They don't normally like that to happen. But once you explain why you're doing this, and what you'll learn from it, and hopefully you can see that each one of those trenches they look really different.

So, the same thought experiment. Is the wine produced on substrate A better or worse, different, than what's on B?

Now we're going to jump across the ocean. We're coming down the home stretch here. You saw two different places with really different characteristics. Now we're in the motherland. Now we're in France, and we're going to start off in Bordeaux looking at the influence of glaciation.

You're probably thinking, "Wait a second. I've been to France. I didn't see no stinking glaciers there. So what are you talking about glaciers?"

Well, back during the glacial maximum when all of Canada was covered by ice, the high country and the Pyrenees, the mountain range between Spain and France, and the Massif Central, in the central part of France, all had big ice sheets on them. So all that material this is what the Pyrenees look like. That was all covered by ice.

And this map and the location map up there. So Bordeaux is here. The Massif Central is a high plateau up in here, all covered by ice. Both the Pyrenees down here and Massif Central fed lots of glacial debris down into this estuary that is Bordeaux.

And so these are various vineyards, what they refer to as the Left Bank and the Right Bank. These are all storied, very, very famous places. You will recognize some of the terms Margaux, Pomerol, Graves in here.

Let me show a cross section through this. The water, the river, sound, is here. These are the slopes where these very famous vineyards are. Graves, if we have any French speakers, "graves" in French means "gravel," OK? You know where this is going.

What was coming down from those glaciers? It was all this gravelly material. Not just gravel, but gravel is in specific what we call stratigraphic layers. All of the top vineyards this is another wonderful story. Back in the late 1800s, all of the vineyards in Bordeaux were classified.

They basically made a classification from what they thought were the very best to the very worst. And one could argue about whether they got everything exactly right, but what they call the "first growths," the number one vineyards sell for ridiculous prices, hundreds, in some cases thousands of dollars a bottle. And all of the first growths are on these stratigraphic gravel layers.

Here's the kicker. There's a particular gravel there, called le Gunz gravel. It's le Gunz high terroir. It's right there. Hold it up there. Château d'Yquem is probably the most expensive wine in the world. It also sells for hundreds or thousands of dollars a bottle, but it sells in these little tenth bottles. You get to pay $1,000 for a tenth bottle. And these are very sweet dessert style wines, and they're grown on a very special substrate that one gravel terrace. Every single one of the top vineyards are on, not just these gravel terraces, but on a particular stratigraphic gravel terrace.

If you go visit the wine areas in France, you're probably not going to hear this story, because they're not geologists. You're getting it now. This is what it looks like, in the field. There's the Gunz gravel. Here's a nice Merlot plant growing on that gravel.

Does this look familiar? Remember seeing this in Washington State? I said, "Christophe Baron, this traveling winemaker, traveled all over all the world. Could have a vineyard anywhere in the world he wanted, and he came to Washington State. He saw that gravel, which, when I first showed it to you, I'm sure you're all thinking, "This guy's nuts. He's been drinking the wine before the lecture again!"

And here it is. Now you begin to see the cause and effect. It's not that you're going to taste this gravel. You don't taste the gravel. You're not tasting what's in the rock. What you are doing is you're tasting the result of the terroir, the environment in which the grapes are grown, that affects the amount of canopy. It affects the acid sugar balance. It affects all those things that I was describing. It mainly comes down to the quality of the wine.

The very last thing, we're going to Burgundy. Now we're getting to the really pricy stuff. This is my very favorite picture in the whole world. I'm standing in a vineyard looking at three different vineyards going up the slope. This is the very last picture I'm going to show you after a cross section.

These have names Chevalier, Montrachet, Bâtard Montrachet. These vineyards have been growing in the same place for almost 1,000 years. That vineyard, right there, has been growing there for almost a millennium. These stone walls separating them are there because that same vineyard has been growing there in that same place with that same wall for 1,000 years. The wine from this vineyard averages close to a $1,000 a bottle.

We come over here to the Montrachet. It's much cheaper. You can pick this up for two or three hundred dollars a bottle. You cross that stone wall. You cross that stone wall to this one, Bâtard Montrachet. Oh, you can pick this up for $125. Where I'm standing, across one more stone wall, is vin ordinaire. You can go to the local cafe and buy this for 75¢ a liter.

That huge difference in certainly cost of the wine, is not a real good correlation between the cost and the quality. That's not where I'm going, but perceived differences in the wine between things that are adjacent.

We're going to ask that million dollar question one more time, "Why?" This is our initial thought experiment that I started this lecture off with. Two vineyards right next to each other, actually three vineyards right next to each other. What is different?

You draw a cross section through this, which geologists love to do. Here's the cross section. Here are those vineyards up there and down at the bottom. I've just blown this up.

So here's Chevalier over here. Limonge. That stone wall is right here. The subsurface this is a fault separating that rock type from that rock type, with different soil horizons. When these vineyards were planted 1,000 years ago, the science of geology did not exist. There was not a human on earth who knew what a fault was, even if they had tried to look. Geology did not exist.

So here's a case where those vineyards are where they are, because over hundreds of years of human experimentation of making wine and trying it over the years, through generations, multiple generations of people, they decided that for my taste, this one is a whole lot better than that one, and it corresponds exactly to these geological features that we can see in the subsurface.

And again, this comes into nutrients and water and all the other things that come together with terroir. And so that's the end of the "Science of Good Taste." If this was a laboratory course, we would now go into the drinking part. We can't, so I thank you for your attention.

For the academically inclined selected readings include:

Apcarian, A., Echenique, M.C., Pavese, J., Jurio, E., Aruani, C., and Meinert, L., 2007, San Patricio del Chañar y Añelo: nueva área vitícola en la provincia de Neuquén, Patagonia Argentina: 11th Congreso Latinoamericano de viticulture y enologia, Mendoza, Argentina, p.1.

Macqueen, R.W., and Meinert, L.D., (eds.), 2006, Fine Wine and Terroir – The Geoscience Perspective: Geoscience Canada Reprint Series Number 9, Geological Association of Canada, St. John’s, Newfoundland, 247 p.

Meinert, L.D., and Nelson, E., 2006, Terroir of Colorado’s Western Slope Vineyards, Society of Economic Geologists Guidebook Series #39, Littleton, CO, 28p.

Meinert, L.D., and Curtin, T., 2005, Terroir of the Finger Lakes of New York: 18th Keck Symposium, Colorado Springs, CO, v. 18, p. 1-4.

Meinert, L. D., 2004, Terroir of Washington State, USA – Influence of Bedrock, Soil, and Climate on Grape and Wine Characteristics: 32nd International Geological Congress, v. 32, part 1, p. 380.

Meinert, L.D., 2004, Understanding the mysteries of the grape: Geotimes, v. 49, #8, p. 20-23.

Busacca, A.J., and Meinert, L.D., 2003, Wine and geology—The terroir of Washington State, in Swanson, T.W., ed., Western Cordillera and adjacent areas: Boulder, Colorado, Geological Society of America Field Guide 4, p. 69-86.

Meinert, L.D., 2003, Terroir of Canoe Ridge, Washington – Influence of bedrock and soil on grapevine vigor and wine characteristics: Geological Society of America, v. 35, p. 186.

Costantini, Edoardo, and Meinert, L.D., 2003, Terroir of Tuscany, Italy – Examples from Montalcino and Poggibonsi: Geological Society of America, v. 35, p. 187.

Meinert, L.D., and Busacca, A.J., 2002, Geology and Wine 6: Terroir of the Red Mountain Appellation, Central Washington State, U.S.A: Geoscience Canada, v. 29, p. 149-168.

Meinert, L.D., 2002, Terroir - What it is and how to use it: Wine Grape Research News, v. 13, p. 2-4.

Meinert, L.D., and Busacca, A.J., 2000, Geology and Wine 3: Terroirs of the Walla Walla Valley Appellation, Southeastern Washington State, U.S.A.: Geoscience Canada, v. 27, p. 149-171.


Title: The Science of Good Taste -- Geology, Wine and Food


November public lecture, presented by Larry Meinert, Ph.D.

Location: Reston, VA, USA

Date Taken: 11/7/2012

Length: 1:02:11

Video Producer: Hannah Hamilton , U.S. Geological Survey

Note: This video has been released into the public domain by the U.S. Geological Survey for use in its entirety. Some videos may contain pieces of copyrighted material. If you wish to use a portion of the video for any purpose, other than for resharing/reposting the video in its entirety, please contact the Video Producer/Videographer listed with this video. Please refer to the USGS Copyright section for how to credit this video.

Additional Video Credits:

Hannah Hamilton, USGS

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