Sustainable Winegrowing

What causes the “red wine headache”? Is it sulfites? A histamine reaction? Andrew Waterhouse, Professor Emeritus of Enology in the Department of Viticulture and Enology at UC Davis and Apramita Devi, Postdoctoral Scholar in the Department of Viticulture and Enology at UC Davis have identified a flavanol that can interfere with the metabolism of alcohol. That flavanol is quercetin, a natural product made in grape skins in response to sunlight. It is a natural sunscreen produced to protect the fruit from ultraviolet light. This conversation covers why quercetin may be more prevalent in high end wines, how skin contact during wine production impacts quercetin levels, and why sulfites may play a role in “red wine headache”. Resources:         74: The Spirit of Wine Andrew Waterhouse Andrew Waterhouse | Google Scholar Andrew Waterhouse | LinkedIn Apramita Devi | LinkedIn Apramita Devi |Google Scholar Inhibition of ALDH2 by quercetin glucuronide suggests a new hypothesis to explain red wine headaches Why Do Some People Get Headaches From Drinking Red Wine?  Vineyard Team Programs: Juan Nevarez Memorial Scholarship - Donate SIP Certified – Show your care for the people and planet   Sustainable Ag Expo – The premiere winegrowing event of the year Sustainable Winegrowing On-Demand (Western SARE) – Learn at your own pace Vineyard Team – Become a Member Get More Subscribe wherever you listen so you never miss an episode on the latest science and research with the Sustainable Winegrowing Podcast. Since 1994, Vineyard Team has been your resource for workshops and field demonstrations, research, and events dedicated to the stewardship of our natural resources. Learn more at www.vineyardteam.org.   Transcript [00:00:00] Beth Vukmanic: What causes. The red wine headache? Is it sulfites or a histamine reaction? [00:00:10] Welcome to sustainable wine growing with the vineyard team. Where we bring you the latest in science and research for the wine industry. I'm Beth Vukmanic executive director. I've been your team. Since 1994, we've brought you the latest science-based practices, experts growers and wine industry tools through both infield and online education. So that you can grow your business. Please raise a glass. With us as we cheers to 30 years. [00:00:37] In today's podcast, Craig Macmillan, critical resource. Manager at Niner wine estates with long time sip certified. Vineyard and the first ever sip certified winery. Speaks with two university of California Davis researchers. Andrew Waterhouse. Professor emeritus of enology and the department. of, viticulture and enology. And. Oprah meta Debbie. Post-doctoral scholar and the department of viticulture and enology. [00:01:04] They have identified a flavonol that can interfere. With the metabolism of alcohol. And that flavonol is called quercetin. A natural product made in the grape skins in response. To sunlight. It's a natural sunscreen produced to protect. The fruit from ultraviolet light. This conversation covers. Why quercetin may be more prevalent in high end wines. How. Skin contact during wine production impacts quercetin levels. And why sulfites may still play a role in that red wine headache. [00:01:36] Want to be more connected with the viticulture industry. But don't know where to start become a vineyard team member. Get access. to the latest science-based practices, experts, growers, and wine industry. The tools. Through both infield and online education so that you. You can grow your business. Visit vineyard team.org. And choose grower or business to join the community today. [00:01:57] Now let's listen. in. [00:02:01] Craig Macmillan: Our guests today are Andrew Waterhouse, Professor Emeritus in Enology in the Department of Viticulture Davis, and also Aparmita Devi. She is a postdoctoral scholar, also in the Department of Viticulture & Enology Davis. Thank you both for being here. [00:02:17] Andrew Waterhouse: Oh, we're glad to be here. [00:02:19] Craig Macmillan: Today we're going to talk about a really interesting topic. It's the role of quercetin , in wine headaches. The two of you recently co authored a paper on this one particular mechanism that might cause some people to get a headache after drinking even a small amount of red wine. But before we get into that, I want to ask you, how did you get interested in this topic? [00:02:37] Andrew Waterhouse: Well I've been talking to Steve Mathiasson. He's a Napa winemaker for actually quite a while, some years back. He suffers from headaches when he drinks certain wines. And we were chatting about possible mechanisms, and we even did a study many years ago with another postdoc in my lab to investigate a question we had or a theory we had, and that didn't pan out. But more recently we were chatting again, and I got interested in the topic again, and that's what got me interested, you know, just somebody knowledgeable who was suffering from headaches and. for listening. It was, it makes it more real and it's like, well, maybe we can figure something out. So that's what got us started. [00:03:17] Craig Macmillan: Apramita , how same for you. [00:03:19] Apramita Devi: Yeah. Same. Like I've been in touch with Andy and we have been talking about this project many years. So I was always interested because I come from biological science and metabolism and stuff I got interested after talking to Andy. [00:03:33] Craig Macmillan: Well, let's start with some basics. What is quercetin? [00:03:38] Andrew Waterhouse: Well, basically, it's a natural product made by grapes, but it's a very specific one. It's in the class of polyphenolic compounds, and it's in the class of flavonoids called flavonols. And what makes it interesting, I think, is that it is made By grapes, in the skin of the grape, and only in the skin of the grape, in response to sunlight. It's sometimes referred to as sunscreen for grapes. And it specifically absorbs UV light that would cause damage to, say, DNA and other macromolecules. So it's very clear that the grapes are producing this in order to protect themselves from ultraviolet light. [00:04:22] Craig Macmillan: Right. [00:04:22] Andrew Waterhouse: So the amount that's present in wine is highly dependent on the amount of sunlight the grapes experience. Not the vine, but the grapes themselves, And a friend of mine, Steve Price, was the first to note this. In a study way back in the 90s on Pinot Noir, he noted that there was more quercetin in sun exposed Pinot Noir grapes. And that observation has been confirmed many times now in different studies. where sun exposure is correlated with quercetin levels. [00:04:58] Craig Macmillan: and this is true just for red grapes as opposed to white grapes. [00:05:02] Andrew Waterhouse: Oh, no, no, there's more in white grapes. But when you make white wine, you throw away the skins. So there's no opportunity to get those materials into the wine. Now, an exception might be orange wine. But I don't know of any data on orange wine. [00:05:21] Craig Macmillan: Apramita , maybe you can talk about the metabolism part, the biology part. So when people consume alcohol, it's metabolized down certain pathways. Quercetin is also metabolized by the body into other forms? [00:05:33] Apramita Devi: Yeah, so the pathway for alcohol and quercetin are a bit different, but the location is liver, where it goes. So when people consume alcohol, it goes to the liver and then there are two enzymes which work on the alcohol. So the first enzyme is alcohol dehydrogenase, which convert it into alcohol into acetaldehyde. The acetaldehyde is the like the toxic metabolite in the body and it can have many side effects. That's why body has to get rid of it out of the liver system. So it has a second enzyme which is called the acetaldehyde dehydrogenase. So that convert acetaldehyde dehydrogenase into a non toxic component, which is acetate or acetic system. [00:06:24] So it comes out of the body. What happens when you consume quercetin along in the body, the quercetin also goes to the liver. Because quercetin adds too much quercetin as such is not good for the body and it has low bioavailability. So liver tag it in the form of quercetin glucuronide and then the body knows that it has to be flushed out of the system. So the interesting part is that when you consume alcohol and quercetin together, You are taking the both the metabolite acetaldehyde and quercetin gluconide in the same location inside the liver. And it gives the quercetin gluconide to interact with the acetaldehyde dehydrogenase enzyme. And that acetaldehyde dehydrogenase enzyme now cannot work efficiently. to convert the acetaldehyde into the acetate. So basically you are building up acetaldehyde in the body and it's not coming out of the system and you are seeing all those negative effects of the acetaldehyde in the form of flushing or headache or not. The other systems like what's like sweating. so we think that there is a correlation between these two pathways, which might be associated in red wine system. [00:07:47] Craig Macmillan: And how did you design your study? [00:07:51] Apramita Devi: The first when I talked to Andy, like he told me that he thinks that this system is because of inflammatory pathways and inflammation system. So he was kind of like, there is something in red wine, which is Triggering this kind of pathways or there is some system so, but we were not sure what exactly are those inflammatory system. [00:08:16] So we went back and saw some literature and we kind of find that there are some studies which told that quercitans inhibit the dehydrogenase enzymes and that what triggered us that okay alcohol is metabolized by these dehydrogenase enzymes. And wine also has these phenolics. So what kind of phenolics, other kinds of phenolics, or what types of phenolics can do this inhibition? [00:08:45] The method was basically in, was based on having different phenolics, which are present in red wines more compared to white wines, select them. And then just, we find this enzyme kits in the market to do this dehydrogenase. Inhibition tests like you put the test compound and it tells whether the enzyme is the inhibited or not. [00:09:09] So we just did that in a test tube system, like we added our phenolics with the enzyme, and we saw that which kind of phenolics are inhibiting this enzyme and screening them out. out of all. So while doing that, we screened different types of quercetin, like quercetin glucoside, quercetin galactosides, and other forms. [00:09:32] Then we also tested other phenolics. I can for all my rest in and other stuff. And we also choose quercetin gluconide because that is the metabolite which is circulating in the body. And then we kind of screen them based on the in the enzyme system and we see how much inhibition is happening there. [00:09:54] Andrew Waterhouse: Yeah. So what we did was a very basic test to experiment. We didn't test anything on people. [00:10:01] We basically tested to see which of these compounds could inhibit that enzyme because we knew that if that an enzyme could be inhibited the acetaldehyde would accumulate and you'd end up with people in that condition would end up with Flushing, headaches, as Aparmita said, all kinds of other symptoms. [00:10:20] Craig Macmillan: And this would vary by person. Different people may have a proclivity to produce more of certain enzymes than others. Is that true? [00:10:29] Andrew Waterhouse: We don't really have any information about that. That's going to take a lot of more work to test you know, the, the details here. For instance. Some people get red wine headaches and some don't, but we don't know whether, for instance, perhaps their enzymes are more inhibited by quercetin glucuronide, or maybe they're just more sensitive to acetaldehyde. [00:10:52] So that's going to take, you know, human studies where we measure a bunch of things. And try to figure out, try to sort through the, the details of how this impacts people individually. [00:11:04] Craig Macmillan: What would a study , with people, investigating this, what would the design be like? How would somebody go about doing that? [00:11:12] Andrew Waterhouse: Okay. So a human study. Could have a couple different possible designs. The one we'll probably use is we'll simply find two wines, two red wines, one that's low in quercetin and one that's high. And then those will be administered to people who get red wine headaches. We'll give it to them blind, they'll have to agree of course to participate in the study. [00:11:37] And then we'll see if their experience of headaches is related to the quantity of quercetin. Now, there's some other designs we could imagine using, which might be a little more straightforward, but we're not sure how relevant they would be or whether we could get approval to do this. So, for instance, one approach would be to find a red wine that's low in quercetin and then simply add it. [00:12:00] Now adding it is tricky for a number of technical reasons. Quercetin itself is very insoluble, so we would have to add what's called a glycoside of quercetin. So we'd have to get our hands on something that would dissolve, et cetera, et cetera. We're not sure we could get approval for that because we're adding a chemical to wine. [00:12:21] Now, the chemical would probably be classified as a supplement, and so it might be approvable, as it were. And then another very simple experiment, which we thought about a while ago, you can buy quercetin as a supplement in the market. It's readily available. [00:12:38] So, one possibility is to simply give our subjects a glass of vodka and give them pills that either contain quercetin or a placebo and see if there's a relationship between administration of quercetin and headaches. [00:12:54] Now the, the quercetin itself, as I mentioned, is very insoluble. So we may have to get these more bioavailable forms of quercetin for that experiment. [00:13:04] Craig Macmillan: That leads to a wine making question. So, if it's relatively insoluble is quercetin extracted from skins more in the alcohol phase at the end of fermentation? [00:13:11] Andrew Waterhouse: Yeah. It's, it's, it's extracted fairly quickly because it's in the skin, in the grapes, it's in the form of what are called glycosides. So these, Has the quercetin molecule with the sugar attached. That makes all those forms very soluble. [00:13:27] Craig Macmillan: Oh, okay. Okay. [00:13:29] Andrew Waterhouse: There's actually an occasional problem with certain red wines, most commonly Sangiovese, where after bottling the wine has had a large quantity of quercetin glucosides. And after bottling, they break down, the glycosides break down, releasing just a simple a glycone, quercetin, and you get this disgusting looking gooey brown precipitate in the bottle. [00:13:56] Craig Macmillan: ha [00:13:57] Andrew Waterhouse: Every few years I know the folks at ETS in Napa get somebody showing up with a bottle of Sangiovese that's got this. Disgusting sludge in it, and they can tell them without analyzing that. Yes, another case, of course, it's in precipitate in the bottom. [00:14:15] Craig Macmillan: Huh, that's interesting. I believe it was mentioned in the paper that , obviously different growing conditions are going to lead to different levels of quercetin and grapes based on how much sun exposure they have, etc. And that also different winemaking techniques would have an impact. [00:14:29] If consumers are looking for products if they know they have a headache issue Is it possible they could experiment with different product types? Products that were made with different production methods if they can find that out that might Impact their sensitivity or might impact how often it happens [00:14:46] Andrew Waterhouse: Yeah, it's a pity that. Consumers wouldn't have information on the level of quercetin. We would very much like to do a study along those lines, but we haven't been able to find any funding for that, just in case somebody wants to support that kind of work, we're happy to work with them. but anyway you know, it hasn't really been an issue for winemakers, so there isn't a lot of data out there. [00:15:08] There are a few studies that published amounts of quercetin, you know, in wines from different places, but the data is very, very limited and not really useful in providing consumers guidance. The one thing we can say is because, as I mentioned earlier, sun exposure is very important, in general if you look at a particular type of wine, a varietal, say Cabernet or Pinot Noir, that the grapes that are grown on very large vines, will have less sun exposure. [00:15:39] Essentially if you have a very highly productive vineyard making targeting an inexpensive line, you probably have much more shading of the fruit as a consequence of lower quercetin levels. Compared to a very high end vineyard, usually, the amount of sunlight is very tightly controlled, and one of the reasons for that is that there's very good data showing that wines that are high in quercetin have a better mouthfeel, better texture in the mouth. And it's not clear whether quercetin is directly responsible or whether it's a marker for something else that's produced under those conditions that leads to that. many years ago, we did a study looking at phenolics in Cabernet, and we observed that the very high end Cabernets that we tested were much higher in quercetin than the sort of average price type product. [00:16:35] And I think that that was true then. It's probably true now that, you know, a very good cabernet is, is made with very tight control of sun exposure. And there is a fair amount, of course, it can't be a complete sun exposure, or they probably get raisins by the end of the harvest, by the time you get to harvest, but there's a very deliberate management of sun exposure in high end wines. And it's for a reason to, get to higher quality product. [00:17:04] Craig Macmillan: Right, exactly! And, We know that the managed sun exposure, quercetin is a part of it but also it's connected to just total phenolics in general. Lots and lots of different compounds that are, you know, semi related. And I actually wanted to go back Aprametia you identified the quercetin glucuronide as being The highest in the ones that you tested, were there other things in that test and that assay that all were also stood out, maybe not as high as that, but really kind of stuck out as being different than the rest. [00:17:39] Apramita Devi: Actually, the quercetin gluconide was a standalone as a very high, like it's like 78%. The other things were around in that 30 percent range, so I'm not sure how significant was the impact of that, but there were quercetin glycosides forms, which were like around 30 percent inhibition of the enzyme, but [00:18:03] all others were very low. [00:18:04] Craig Macmillan: yeah, so it really stood out basically as it was head and shoulders above it. I would like to put this work into context a little bit. I, I work with the public quite a bit as part of my job and I have for years. And this topic comes up. All the time. This information definitely helps me my goal, when I talk to a consumer that has an issue with, wine headache or whatever it's not that I'm trying to sell them a product as much as it is. [00:18:29] They want to enjoy wine. They tell me this, they say, Oh, I love to have it. I just can't. Da da da. And then they'll say, it's like sulfites. And then I'll kind of explore that with them a little bit. Like, so can you eat dried fruit? Do you eat canned fruit? Do you have reactions to this or to that? Are you asthmatic? [00:18:48] Kind of sort that out and go, okay, I don't think maybe that's it. Maybe it's not. The other ones that I just learned about about 10 years ago was a biogenic amines, which made a lot of sense to me in terms of things like histamine reactions. What is your feeling about sulfites is contributing biogenic amines. [00:19:04] Maybe there's other things we haven't hit on, on this topic. What are your feelings about the, kind of the big picture of what potential for a diagnosing assist? [00:19:15] Andrew Waterhouse: Why don't you talk about amines [00:19:16] Craig Macmillan: Yes, please, [00:19:18] Apramita Devi: Biogenic amines like mostly the histamine and tyramine are the main ones people talk about whenever they come with this headache stuff. So I think because it's formed in the wine during the fermentation process, and there are these spec microbes which can convert the amino acids into this, biogenic amines the histamines are part of inflammatory reactions. People know that in biology and immunology. So it's very easy to be people connected that it might be a reason why people get headache. But what I always focus is like, there are far more other food products, for example, fermented meat products, which has far more higher amount of these biogenic amines. do people get headache if they have something similar with alcohol eating together with alcohol or something like that? But there is no mechanism told till now, they just tell that, oh, since it's histamine and it's related to this inflammatory reactions, it might be the cause. But there is no solid proof that it is the cause. [00:20:27] so I don't know whether it's there or it might be a pathway or not. [00:20:33] Craig Macmillan: One of the things that I find fascinating is how we evolve our, Hypotheses about things over time, and somebody has an hypothesis and they test it out, maybe they find something, maybe they don't, but then that kicks off this whole set of what I call naive science making up stories about why. [00:20:53] It's kind of a just so story. It's like, well, obviously then somebody comes along and checks it and says, Hey, wait a second. And we're no, or if this was true, then that would have to be true. And that's not true. You know, and that kind of thing and how we keep coming around to new ideas, which is what you folks have done, which I think is really, really cool. [00:21:10] Andrew Waterhouse: I was going to answer your question about sulfites. It's a really big question actually. Partly because sulfites have so much visibility and there's so much concern about it. I think sulfites themselves Have been studied pretty carefully there's one study where if they gave subjects a very high level of sulfites in wine, it was like very small, but statistically significant increase in headaches. [00:21:39] Or some adverse reaction, but other studies have shown no correlation. By the way, sulfites are antioxidants in case you hadn't heard that. So it seems very unlikely that sulfites by themselves are some sort of bad actor in this regard. Like you, I get these questions all the time. And what I heard so many times was. Oh, it's cheap wine. It gives me a headache. [00:22:06] Craig Macmillan: Yes. [00:22:07] Andrew Waterhouse: And have you heard [00:22:08] Craig Macmillan: I've heard that many times. And then on the opposite side of things, I've heard stuff like, Oh, I get headaches from American wine, but I don't get it from French wine. Or I always get headaches from European wines, but I never from California wine. So I'm trying to figure out, is there something going on? [00:22:26] Like, can you be allergic to burgundy? You know what I'm saying? Cause I mean, it could be, it could be something about burgundy. It's just stuff going on. And then the opposite. I had a guy who says, no, I don't have any that. But he says I was traveling in France, and we were drinking wine like it was water, and I never had a hangover symptom, and I did it, and I was like, I don't know dude, like I [00:22:45] Andrew Waterhouse: Yeah. Well, there's, there's one answer to some of this, which is if you're on vacation and you don't have to get up early and you're relaxed and you probably don't get as many headaches. [00:22:58] Craig Macmillan: Right. [00:22:59] Andrew Waterhouse: So I think that's a large part of it, especially for Americans visiting Europe. They're on vacation. but I think there is something to the sulfites question. And that is that inexpensive wine often, not always, but often has more bound sulfites. [00:23:18] Craig Macmillan: Yep. [00:23:19] Andrew Waterhouse: And this is probably because those grapes have a little bit more mold on them or a lot more mold. And when they get to the crusher, the winemaker goes, Oh, there's mold on these fruits. So we're going to add sulfites to, to take care of the botrytis, right? [00:23:34] We don't want the fruit to get oxidized and damaged. They had a bunch of sulfites. The consequence of that is that in the finished line, There's a lot more. Bound to SO2, which shows up in the total SO2 number. [00:23:47] You know what it's bound to? [00:23:49] Craig Macmillan: No. [00:23:49] Andrew Waterhouse: It's bound to largely acid aldehyde. [00:23:52] Craig Macmillan: Really? [00:23:53] Oh! Well that would make sense. Yeah, that would make sense. [00:23:56] Andrew Waterhouse: And the, the reason for that is that during the fermentation, the yeast are converting all this sugar the alcohol, but there's an intermediate step which is acetaldehyde. [00:24:06] Craig Macmillan: Right. [00:24:07] Andrew Waterhouse: If you have SO2 floating around, as you would if you'd added a lot of it up front, it binds that acetaldehyde before it gets reduced to ethanol, to alcohol. if you start a fermentation with a high level of added SO2, then you will end up with a wine that has more bound acetaldehyde. And that could be a marker, say, of less expensive wine. [00:24:31] So it's possible that those people are, what they're experiencing is direct ingestion of acetaldehyde, which is being released into the blood and that that's causing them a problem. [00:24:45] Now, I've looked and looked, and I cannot find any data on what's called absorption of acetaldehyde from wine, or from food for that matter. I keep, I'm going to keep looking, [00:24:56] but for some reason or other, this hasn't been subject of a published study, although maybe I just haven't been competent enough to find it. [00:25:05] Craig Macmillan: I doubt that. [00:25:07] Andrew Waterhouse: Well, sometimes these are, you know, they're very specialized and they're indexed in funny ways. And, [00:25:13] You know, and the other thing was, you know, when the study came out, I had all these questions. I was talking to this one reporter and she said, well, I can drink natural wine. [00:25:24] It doesn't give me headaches. And I was like, oh boy, what's this about? [00:25:27] Craig Macmillan: Yeah. [00:25:28] Andrew Waterhouse: But thinking about that further when you make natural wine, you don't add any sulfites or at least you're not supposed to, Right. And consequently in the finished wine, the level of acetaldehyde would have to be very low or else it would smell like sherry. [00:25:41] Craig Macmillan: Right. Right. [00:25:43] Andrew Waterhouse: And yes, granted, many natural wines have funky smells, but they don't by and large smell like sherry. [00:25:49] So it's possible that natural wines have in general, Much less acid aldehyde than conventional one. you know, all these questions have brought up some interesting issues, I think, you know, the industry should be looking into you know, these are these issues like how much acid aldehyde Do we want in our wine and how can we reduce it if we want to reduce it? [00:26:15] I don't think anybody's really looking at that yet. I think that would be a very interesting question to pursue. Oh [00:26:24] Craig Macmillan: you just, you just reminded me of, of something two things that I, I had forgotten about. One I used to teach like enology for babies, enology for dummies thing for the public. I am in no way qualified other than just experience to do that. [00:26:39] But I broke it down in that I do that sugar aldehyde, alcohol arrows, and I'd say, okay, this, this acid aldehyde. Remember this one? This one's coming back. We're going to see this again later. So write this one down. We're going to get to that later. And sure enough, now it's just through the body and, and I think breathalyzers work based on that. [00:27:00] Don't they? It's like density. Something like that. So the aldehyde, they're actually, [00:27:05] I think so. I got to look that up again, but because by the time it gets to your breath, your body's, Processing it, right? Hugely important. Not just that compound, but aldehyde is just kind of a general well, maybe we should all invest in like some kind of, I don't know, AO unit or wine X ray or something at our house. [00:27:21] And then we could get the totals and know before we drink it you know, maybe we could figure out if somebody could come up with a consumer friendly, you know, put it in a vial and shake it and it turns blue. Don't drink it kind of thing. I'm just being silly. I don't know. [00:27:34] Andrew Waterhouse: idea. [00:27:35] Craig Macmillan: You go to different like wine shops and stuff, and there's all kinds of stirs and additives and strainers and funnels and stuff that are supposed to take things out. [00:27:45] And I've always really wanted to see what those things do. They do anything or not, or I don't know. I'd like to try it. Finally, is there one takeaway on this topic, this question to both you, one takeaway you'd like people to know, I [00:27:57] Andrew Waterhouse: well, I think the key thing is that we haven't done any experiments on people yet. [00:28:03] Craig Macmillan: Right. [00:28:04] Andrew Waterhouse: And so what we have here is, I would call it a well founded theory, [00:28:09] Craig Macmillan: Mhmm. [00:28:09] Andrew Waterhouse: I think people shouldn't rush out and start changing the way they drink yet. They might want to try some experiments. But we don't have the final word yet. [00:28:20] Craig Macmillan: Right, right. [00:28:24] Apramita Devi: Same. Yeah. This is just very preliminary study. And we just have a theory out. So we still don't know, like, what happens in the actual body. [00:28:34] Craig Macmillan: Well, I hope that we can do that. [00:28:36] Andrew Waterhouse: We're always looking for support for experiments. If anybody wants to support that, get in touch. [00:28:43] Craig Macmillan: You know, another creative thought that I have when I'm preparing for this is like, you know, , people either get headaches from wine or they don't. If I'm someone who wants to enjoy wine, but gets headaches, I would be really attracted to a product that had a back label if we could make health. statements, which we cannot, that would say now low in quercetin or, you know, headache free, you know, no, we would never get that through TTP, obviously, but but, but, you know, but we went round and round with that on sulfites, you know you know, organic waste, no added sulfites, you know, you can say that. [00:29:14] Andrew Waterhouse: I think it would be possible to perhaps have a declaration on a bottle about the level of quercetin, whether it's high or low. I suppose. I don't know. [00:29:24] One company did get a label through that had resveratrol levels on it, but then TTB stopped approving that. So only one company has that approval. But I think in that case the reason for denying the label is that it is a proxy for health claim. Thank you. [00:29:44] Quercetin, you know, whether it's high or low is really, it's not, it's not making a health claim. We're not claiming that this wine is healthier for you than the other has to do with headaches or not headaches. [00:29:55] And I don't see that as really a health claim. [00:29:58] Craig Macmillan: Well, let's just see how this develops. You never know. Let's face it. I mean, we're talking about nutrition. This is August of 2024, the date for this recording. We're talking about having nutritional labeling on wine. Right? Which I think would be a very interesting nutritional label, quite frankly. [00:30:13] I would, I would love to see that, you know. Zero percent of the RDA of everything, again, at the end of one of my lectures I'd introduce potassium, and at the end I'd say, so how much wine do you have to drink to get your RDA of potassium? You have to drink a gallon and a half of wine a day. So, maybe not a big contributor. Maybe not a big contributor. Where can people find out more about both of you? [00:30:37] Andrew Waterhouse: Well, I think probably the best starting point would be our LinkedIn pages. [00:30:43] Craig Macmillan: And those will be in the show notes. [00:30:45] Andrew Waterhouse: and I do have a website at UC Davis called waterhouse. ucdavis. edu. [00:30:52] Craig Macmillan: And that will be in there as well. What about you, Apremita? [00:30:54] Apramita Devi: For me, LinkedIn page. [00:30:58] And if people want to see about my research or my past research, they can go to my Google Scholar page to [00:31:05] Craig Macmillan: Awesome. Thank you. Well, thanks so much for being here. Our guests today were Andrew Waterhouse, Professor Emeritus in the Department of Viticulture and Enology at UC Davis, and Apramita Devi, a postdoctoral researcher in viticulture and knowledge at UC Davis. Really interesting work. [00:31:21] I'm glad that you folks are doing it. I've been a big fan of you, Dr. Waterhouse, for a long time, and now that I've seen your work, I'm a big fan of you. Apremita. You've done some pretty cool stuff in the last five years. So again, thanks. And thank you for listening to Sustainable Wine Growing with Vineyard team. [00:31:38] Please keep downloading episodes. Please visit the show page. Lots of information there. And we also have a new publication, Understanding Wine Chemistry by Andrew Waterhouse, Gavin Sachs, and David Jeffrey. Is that correct? [00:31:53] Andrew Waterhouse: That's correct. [00:31:55] Craig Macmillan: This is out in the world now. [00:31:57] Andrew Waterhouse: It's just out this month. [00:31:59] Craig Macmillan: That sounds like a must have. [00:32:01] Andrew Waterhouse: I agree. [00:32:03] Craig Macmillan: That sounds like a must have. , I will leave the name out, but there was a very famous book written by a group of folks from CSU Fresno and some collaborators. And I don't have a copy because I bought five copies in my cellar. People stole them every single time. So, this is the same kind of book, folks. [00:32:20] Maybe buy five copies. And just hand them out to give one to your assistant winemaker. Give one to your cellar master and just say, here, these are yours. I'm keeping my copy. Thank you very much. That's, that's really cool. And again, thanks for being on the podcast. [00:32:33] Beth Vukmanic: Thank you for listening today's podcast was brought to you by wonderful laboratories. Wonderful laboratories operates two state of the art high throughput laboratories. He's located in Shaffer, California to support pathogen detection and nutrient analysis. The team provides full service support to customers with field sampling. Custom panels and special projects. They're. Customers include pest control advisors, growers, consultants, seed. Companies, backyard gardeners, ranchers, and more. [00:33:10] Make sure you check out the show notes. To learn more about. Andrew. And Oprah meta. To read a great article about their research. Why do some people get headaches from drinking red wine? [00:33:19] And if you're looking. Looking for. Some more fun wine at trivia to share at holiday parties this season. Listen into sustainable Winegrowing podcast episode. 74, the spirit of wine. [00:33:31] If you liked the show, do. It's a big favor by sharing it with a friend subscribing and leaving us a review. You can find all of the [email protected] slash podcast. Podcast. And you can reach us at [email protected] until next time, this is sustainable. Winegrowing with the vineyard team. [00:33:49]   Nearly perfect transcription by Descript

[00:00:00] While, the year is nearing its end. There's still a lot of actibity and work ahead with the holidays. This marketing tip. We'll give you ideas for a greener holiday season. Use them in the tasting. Room. And at home. Welcome to Marketing Tip Monday. With sip certified. We know that customers are looking for wines labeled as sustained. Sustainable. While our longer-form episodes help you learn about the latest. Latest science and research for the wine industry. These monthly. Monthly micro podcasts will help you share your dedication to sustainable winegrowing. [00:00:33] Now let's get into some. Some tips for greener gatherings. [00:00:37] Consider getting a. A living tree rather than a cut or artificial tree. With the right tree and. The proper care it can survive the holiday season and then be planted on your property. [00:00:47] Use led lights for decorating your space. They use up to 90%, less energy than traditional incandescent. Bulbs. And can last up to 25 times longer. At an. Average of 30 cents a kilowatt powering 500 incandescent. C9 bulbs, eight hours a day for 30 days. It would cost $294. While the same five. 500 led bulbs would only cost $37.80. That's also sustainable savings for your pocket book. Plus many led lights have features like dimming. Color adjusting and motion detection. So you can customize your look and. Use them for other occasions. [00:01:27] Do you have holiday events on your calendar?. There are many options for biodegradable plates. Bowls and cutlery. Add them to your compost heap or. Send them to an industrial composting facility. Just be sure not to recycle. Recycle them organic materials can damage recycling equipment. And don't put them in the trash organic waste and landfills could produce methane gas. [00:01:49] And who. Who doesn't love local goods. Invite local vendors into your retail space. Base. To give your guests some locally sourced gift options bonus. Points. If they use natural or recycled materials. Alternative. you could opt for the gift of a local experience like dinner for two a spa day or certificate to a local shop. [00:02:08] Oh, the ribbons and bows, but where do they go? [00:02:11] When it comes to sustainability over the holidays. Days we need to address packaging. [00:02:15] For those of us who aren't the paper and ribbon collector. At the gift exchange, use. Just wrapping materials can be recycled. Plus some can even. And be composted. [00:02:24] Make sure. You check out. At the show notes to link to this article called holiday marketing. Marketing tips. To review an awesome chart. To help you gift. Wrap the Greenway. It covers what kinds of wrapping paper? Tissue paper, gift bags, boxes, ribbons, and bows can. Can be recycled. Composted. Plus some creative alternatives like wrapping. Packaging in a tea towel. And making your own paper bows. [00:02:50] Here's a bonus tip. Check out. Tip number two. In the five sustainable tasting room habits, marketing tip. To learn a few more responsible recycling practices. [00:03:00] This February. We'll continue the celebrate. Celebration of sustainable wine and we'd love for you to come celebrate with us at reciprocal, February over 30 sip certified brands have. I already joined. [00:03:12] And you can join to. Share. ReSIProcal club tastings with participating brands to increase your traffic and. Connect with like-minded brands and wine enthusiasts who value sustainability. [00:03:21] Until next time, this is sustainable. Winegrowing with the vineyard team.   Nearly perfect transcript by Descript.   Music from #Uppbeat (free for Creators!): https://uppbeat.io/t/pecan-pie/happy-holiday-swing License code: QEFYRHVU5DRTFHPW Resources: *** Tell Your Sustainable Story Online Course *** Apply for SIP Certified Wine Join ReSIProcal February 2025 Marketing Tips eNewsletter Sustainable Story | Print Sustainable Story | Electronic Tips for Greener Holiday Gatherings What's your Sustainable Story? Vineyard Team Programs: Juan Nevarez Memorial Scholarship - Donate SIP Certified – Show your care for the people and planet  Sustainable Ag Expo – The premiere winegrowing event of the year Sustainable Winegrowing On-Demand (Western SARE) – Learn at your own pace Vineyard Team – Become a Member

Want to practice regenerative agriculture? Daniel Rath, Agricultural Soil Carbon Scientist at Natural Resources Defense Council recommends that you start by asking what you want to regenerate. Beneficial practices including integrating livestock, crop rotations, cover cropping, minimizing tillage, increasing diversity, improving soil health, adding organic matter, and reducing external inputs will vary site to site. A long-term study found that these practices improved above and below ground biodiversity, increased water storage and infiltration, bolstered resilience to climate change, increased carbon and organic matter storage, and, impressively improved human health. Listen to the end to learn how soil metagenomics has the potential to not only tell us what is living in the soil but how the organisms interact. Resources:         231: Stacking Regenerative Practices to Create a Healthy Vineyard Daniel Rath Daniel Rath on Google Scholar Daniel Rath on National Resources Defense Council (NRDC) Healthy Soils Playlist (podcast play list) NRDC Regenerative Agriculture 101 page Soil Biodiversity in California Agriculture What the Soil Can Teach Us | Daniel Rath | TEDxBelmopan Wine grape grower perceptions and attitudes about soil health Vineyard Team Programs: Juan Nevarez Memorial Scholarship - Donate SIP Certified – Show your care for the people and planet   Sustainable Ag Expo – The premiere winegrowing event of the year Sustainable Winegrowing On-Demand (Western SARE) – Learn at your own pace Vineyard Team – Become a Member Get More Subscribe wherever you listen so you never miss an episode on the latest science and research with the Sustainable Winegrowing Podcast. Since 1994, Vineyard Team has been your resource for workshops and field demonstrations, research, and events dedicated to the stewardship of our natural resources. Learn more at www.vineyardteam.org.   Transcript [00:00:00] Craig Macmillan: Our guest today is Daniel Rath. He is a soil scientist with the Natural Resources Defense Council. And today we're going to be talking about regenerative agriculture. Thanks for being on the podcast, Daniel. [00:00:10] Daniel Rath: Thanks a lot, Craig. I'm excited to be here. [00:00:13] Craig Macmillan: We've been trying to find folks to talk about regenerative agriculture because it's a real buzzword right now. [00:00:18] And it's a buzzword in the vineyard industry, but it's not vineyard specific. This is applying to all sectors of agriculture and globally. This is a big concept now. So that's inspiring and drawing a lot of people, uh, in different directions. But I get different definitions of it. What regenerative agriculture? [00:00:37] Daniel Rath: Well, first of all, I'll say it's not really surprising that you get a different definition depending on who you talk to because, you know, regenerative agriculture really hasn't been like very specifically defined yet the way I think about it. Part of the reason it's so hard to define is that it's really more of a philosophy and an approach to land management. [00:00:59] And so, you know, it's taking into acknowledgement the fact that agricultural systems have this complexity. And instead of trying to reduce that complexity, we lean into it. We see what advantages we can get from it. It's a holistic approach. You know, it doesn't just necessarily focus on the environmental impacts, but what are the social impacts? [00:01:18] What are the economic impacts of agricultural systems? Looking at things like local food systems and connecting farmers to consumers, but also how do we increase soil health? How do we reduce pests and diseases? It's funny. You should bring it up now. The state of California. Just finished a process in of defining regenerative agriculture for their legislative effort. [00:01:40] Craig Macmillan: Oh [00:01:41] Daniel Rath: Yeah, there's a draft definition out there have been numerous listening sessions The next one is on august 22nd, but I was part of that committee that tried to like Capture this sort of like ephemeral philosophy and like nail it down without hopefully killing it. [00:01:57] Craig Macmillan: Uh, and to put a timestamp, the date of this interview is August of 2024. [00:02:03] So this is new to that point. We'll see how that develops from here. Which is pretty cool, but no, I was not aware of that. That's pretty, pretty interesting. What are some of the specific practices somebody might use? So, philosophically, I'm in alignment. I want to build and protect my soil. I want to protect my community. [00:02:20] I want to have healthier plants. What are some of the techniques that folks are using around the world to do this? [00:02:26] Daniel Rath: Well, I will answer your question with a saying that my PhD advisor used to tell me every time I walked into her office, which was that, you know, what is your goal? What is the question that you're trying to ask, right? [00:02:37] Part of the reason that regenerative agriculture does not have one set definition is that it's going to look very different. different depending on where you are. A regenerative agricultural system in a place that is facing a lot of restrictions on water, low soil organic matter, the practices you use there are going to look very different than say if you have regenerative agriculture in a place that has regular rainfall, has a lot of soil organic matter, very active soils. [00:03:02] I would say that some of the most commonly mentioned practices are things like integrating livestock into perennial systems, cover crops, crop rotation, increasing the diversity on farm systems, reducing tillage, basically all of these practices that increase soil health, because really increasing soil health is at the the core of what it means to sort of regenerate a plot of land. [00:03:29] But if you're talking about specific practices, you kind of have to think like, well, what am I trying to regenerate? What are the goals that I want to get out of it? One other interesting topic is the idea of reducing external inputs, not eliminating them entirely, but reducing dependence on things like fertilizers and pesticides, seeing how a that can result in cost savings for farmers, but also Relying on the natural complexity of the system to provide those benefits. [00:03:58] Craig Macmillan: Yeah, that's always been one of the tenants of sustainable farming is to reduce the number of off farm inputs and reduce the number of farm outputs other than the crop, and that includes things like pollution, erosion, whatever, um, and try to develop a system that's stable in and of itself. Um, and it sounds like there's some things that can contribute to that. [00:04:18] Um, what about composting? That's another popular topic. [00:04:21] Daniel Rath: Composting, I forgot to mention that composting really adding organic matter to the soil. A lot of the systems that we've developed over the last few decades are very focused on adding nitrogen, which is important. Nitrogen is a really big limiting nutrient, but we've learned that adding nitrogen on its own is not enough. [00:04:38] You have to add carbon in there. You have to add other micronutrients that might not be contained in your typical fertilizer mixture. And so yeah, adding compost is a really great way adding organic matter residue crop. [00:04:53] Craig Macmillan: Again, the inclusion of animals seems to be, um, pretty consistent across different definitions, including mobile cropping systems. [00:05:00] In permanent crops that can be a little tricky. So like in vineyards, I have heard of folks that were grazing goats and sheep in season for the most part. Folks will plant a cover crop in the winter and then maybe they'll come through with some sheep or some goats in the springtime. I guess my question is, when I read other things and they talk about having animals as part of the system, I see like herds of cattle, which are generating a lot of manure. [00:05:25] And I can go, yeah, I, I bet that's doing a lot, but your smaller ruminants, in your opinion, I mean, can they contribute enough in a, in a, a seasonal, uh, past to, to make a difference? [00:05:39] Daniel Rath: Yeah, this, that's a really good point. I think the short answer is, yeah, I think they do. And so the example you gave is, I think the one I would have used, right, is that planting cover crops in between these sort of like, vines that are there for a long time, and then using ruminants to terminate those cover crops and to convert it into manure and urine, which was a great source of nitrogen. [00:06:00] When I was at UC Davis doing my PhD, we had a couple experiments on sheep terminating cover crops and goats terminating cover crops. And you could see the benefits in the soil, as long as you had those like livestock ruminants being on the plot. [00:06:15] Craig Macmillan: That leads to another question. You know, I've got the philosophy now. [00:06:19] I believe in the philosophy. I believe that I can actually improve the soils. One of the things I've always been a little suspicious of with regenerative agriculture is the idea of regeneration. I have a hard time kind of making sense of that in my mind in agricultural systems because things are leaving. [00:06:36] And certain crops are not big miners. Wine grapes are kind of famous for not really mining the soil that much and they can grow in very poor soils Doesn't mean you don't want to build those soils, but if I'm looking to detect what we would call regeneration, what kinds of Variables might I be looking at and what are the kinds of things that I might actually be able to get some metrics on? [00:07:00] Where I can say yes, this program seems to be working This is making a difference or I'm not seeing the results that I would like Maybe I should make a shift and try something different [00:07:09] Daniel Rath: Yeah, that's also a really good question. So I think there are actually two really interesting questions in what you just said. [00:07:15] The first one is, what do you measure? And again, it depends on your question, but very often the things that we will measure will be things like soil organic matter, right? We will be looking at measurements such as nutrient balance. So how much nitrogen is soil's organic matter, what are the nitrate and phosphorus levels in the soil for wine grapes? [00:07:36] I know you don't want it to be like too fertile because it is good to stress those grapes out a little bit to get a high quality product. You look at things like drainage and water storage. If you see better infiltration on plots, if you don't see water ponding quite as much. One thing that is becoming more common is tracking microbial indicators, right? [00:07:56] And so part of the reason that we do that is that microbes are like early indicators. They will change faster than the soil organic matter content. And so they can give you an idea of where you're headed and whether or not it's a direction you want to be heading in. I can, you know, apply to stuff like pest and disease too. [00:08:15] Craig Macmillan: This is a great one because I've been working on this for the last couple of years. What am I looking for? I, uh, there's a bunch of different tests that you can do. There's a bunch of different things you can look at. If I'm trying to get a sense of what's happening with the cell microbiome, what kind of testing might I be interested in doing? [00:08:30] What kinds of things might I specifically be looking for? [00:08:34] Daniel Rath: There have been a lot of advances in the last, you know, decade or so looking at this. One of the biggest areas that there have been advancements is tracking the incidence of pests and diseases, right? And so, you know, that is a really good one. If you're worried or, you know, concerned about a specific pest, there are often really good methods to test for that. [00:08:52] You can also be looking at biological tests that look at functions of interest. So say your goal is to reduce nitrogen application on your plot. There are measurements that you can make of nitrogen release from organic matter by microbes and that will give you a really good idea or, you know, a fairly good idea of maybe how much nitrogen this soil is already supplying. [00:09:17] California is also really interested in this. So another thing, there's a soil biodiversity report that came out about a year ago in which the CDFA asked us this very question. They were like, if we were going to measure soil biology across California for a number of different purposes, what would we do? [00:09:32] We had 15 scientists that have really been working on this for a long time. We all sat down and like, how do we capture the thought process and thinking that goes into this? into selecting the right microbial indicator because there are a lot of them and they're not all easy to interpret. [00:09:47] Craig Macmillan: Are those recommendations out there now? [00:09:49] Daniel Rath: I would say the, the report is out and in the report we, you, we have a couple examples. We're really hoping that the California Department of Food and Ag will sort of expand on those recommendations for more like, sort of like a targeted approach. Really what we did is we used that nitrogen example as an example. [00:10:10] It's like this is how you would do it, but really the devil is in the details. What is the specific area you're looking at? What is like the question you're looking to answer? The biodiverse report has at least like the thought process, what are the things you should be looking for? [00:10:25] Craig Macmillan: So we've been talking about kind of like more short term. [00:10:27] What about long term? You have some experience, I believe, in long term agricultural research. Like, I think you did a study that was like a 25 year retrospective, if you will, of the health of a particular farm. In the long term, in the longer range, What kinds of benefits should we expect? We've talked about pest and disease resistance, maybe water status. [00:10:51] What kinds of slow changes might we be looking for that we might see that would give us some confidence that this is working? [00:10:58] Daniel Rath: Sure. I mean, this is an example of why long term experiments are so great because. They're the only really way for us to get at this question. But you can expect things like improved biodiversity on, um, especially above ground biodiversity, below ground biodiversity. [00:11:15] That is a process that takes a long time. You can see things like improved water storage, improved water infiltration. You can see You know, if you're talking about the ultimate long term metric resilience, right, how do our agricultural systems respond to the climate changes that are already occurring and, you know, building that resilience means relying on this like complex biological network that really sustains our plants right now. [00:11:46] Increased carbon and organic matter storage is another really good one. And so, you know, over time you see all of these environmental benefits and along with that comes social benefits. We see improved human health. We see improved connectivity between farms and the communities nearby. Improved sort of farm worker health and safety. [00:12:07] All of these things are a little bit longer term, but they are all one of some of the goals and some of the benefits we see from regenerative systems. [00:12:16] Craig Macmillan: I want to drop back to one of the practices because I've talked about this quite a bit with folks. I want to get your take on it. No till or minimal till. [00:12:24] Or, uh, I talked to one person that said, uh, avoid excessive tillage. And the question that came back was, what the heck is that? What's excessive? You know, what, if I drag the disc through here one time, is that excessive? And this may apply to other crops that you've worked with. What role does tillage have in this process, in these systems? [00:12:45] Because one school of thought that I'm familiar with is, okay, we grow these cover crops, we terminate them with sheep, it's great, but we may still want to incorporate that material into the soil. So that it breaks down and gets in there. Then there's another school of thought that says, No, don't do that. [00:13:03] Don't touch it. Leave it alone. Let the system do what it normally does. And then there's a third school of thought that's like, well, I can't do that forever. Floors get too bumpy. Um, things need to be reset. Or I need to plant cover crops. So I need to set a seed bed. And again, you can draw from other cropping systems on this. [00:13:21] What is your feelings about the effect of tillage on the soil microbiome and soil health discrimination? [00:13:26] Daniel Rath: No, no till has been a really hot topic for quite a while. It came about when the NRCS was first started looking to reduce the impacts of a dust bowl and realizing that tillage was over tillage was a major cause of that. [00:13:41] And so when you are looking at no tillage, there are very clear benefits. There's increased plant root presence, decreased erosion, better soil structure formation, a potential for better infiltration. But you have to wear that against the. benefits of tillage. I mean, it has very clear benefits too. It helps to keep weed and pest populations under control. [00:14:03] It makes it a little bit easier, especially in annual cropping systems for roots to establish. Like you said precisely, it's a better way for incorporating organic matter into the soil. My point of view is that I think tillage is a valuable tool in the farmer's toolbox, right? And that what is over tillage is going to really depend on where you are. [00:14:24] If you're on a slope, probably less tillage is better because again, you don't want that top soil to be washed off. If you're on sort of like a flat plain and you know, you know, you're tilling to establish a crop, then it's probably not a big deal to have one or two tillage passes, at least from the erosion standpoint. [00:14:41] What we do know is that no till has also been recommended as a way to increase soil carbon. There's still, I think, a little bit of back and forth on that. At least we have seen is that no till increases soil carbon at the top. Part of the soil really doesn't increase at the bottom. So it's more of a redistribution of carbon again There are really clear benefits to tillage and you know There's a reason that people have been doing it for a long time [00:15:07] Craig Macmillan: kind of what I'm hearing I think this is a really great message is it's another tool. [00:15:11] It's a tool that we don't have to throw away But it is one that we should think about how we use it. I've, I've actually started to think about tillage the same way I think about, uh, pesticides and fertilizers. Where it's, it's a question of what benefit am I going to get from this? Do I need to do it? [00:15:28] Are there other things that I could do? And then you put that all into your calculator in your brain and, and try to sort it out. And I've had some very interesting conversations as how different people kind of sorted those things out. So I think that's a great point. That leads me to another question that I just thought of. [00:15:42] And so the role of synthetic fertilizers, for instance. The synthetic fertilizers have been pointed to, and I think accurately so, as driving land degradation in many cases, especially the overuse of nitrate based fertilizers. You also have environmental impacts in terms of pollution, potentially. Is there a role for conventional fertilizers in regenerative agriculture? [00:16:05] Daniel Rath: Yeah, well, that's a real hot button topic there. Yeah. [00:16:10] Craig Macmillan: Hey, we go, we go for deep water on the show. Inquiring minds want to know. Hey, [00:16:16] Daniel Rath: that's, that's a real good question. Honestly, that's a question that I has been taking up a lot of my professional time recently. Like you said, it's not a secret. We are seeing a lot of negative environmental impacts from Over application of fertilizers that includes nitrate pollution in groundwater that applies to pesticides as well. [00:16:36] You know neonic pesticides have had major problems with insect populations. I think that exactly What you said you need to sort of weigh the costs and benefits Of these like particular practices and you know In my work in my phd talking to farmers the sort of farmer calculus that occurs in like You know, in the minds of the folks that I work with is so complex. [00:17:00] There are so many factors that you have to balance. One thing to be aware of is that we are applying too much nitrogen fertilizer now, and that's pretty clear from like the negative environmental impacts that we've seen. And so it's less of an idea of like. Like how do we eliminate nitrogen fertilizer and more like how do we make sure that that fertilizer gets into the plant? [00:17:23] You know, how do we match that fertilizer application to what the plant actually needs instead of over applying, right? How do we keep it on the plot? Because it is expensive. No one wants it to be running off into the environment, [00:17:36] Craig Macmillan: right? [00:17:37] Daniel Rath: One of the things that has really come across to us is when we talk to folks about nitrogen fertilizer application, there are yield benefits, but very often it's also a risk management strategy. [00:17:50] You want to apply enough nitrogen fertilizer so that if conditions are ideal, you can take advantage of them. Really and truly, there have got to be better, less environmentally intensive solutions. impactful risk management strategies. You know, that includes looking at the way that we incentivize crops, looking at the way that we handle crop insurance, looking at the crop choices. [00:18:13] If you're in a area that has a lot of potential for agricultural runoff, it may be better to grow crops that do not require as much nitrogen, corn is very greedy, or to put systems in place that reduce that nitrogen runoff, cover cropping, riparian buffers, All of these things are like great ideas to get to the underlying goal, which is reducing the need for nitrogen fertilizer. [00:18:39] Craig Macmillan: That's perfect. Gosh, we just keep getting more variables, don't we? [00:18:42] Daniel Rath: Oh my gosh, I assure you that's [00:18:46] Craig Macmillan: And speaking of more variables, I want to switch topics now. This is great, background graded by some regenerative agriculture. I know that I now have a better sense of what the philosophy and the practices are. [00:18:56] However, you've also worked in the area of soil metagenomics and metagenomes. And this has come up in other interviews that I've done around soil health with soil microbiologists. What is soil microgenomics and where are we at and where are we going and what can we do with this and what's all the exciting stuff coming down the pipeline? [00:19:19] But first of all, what, what is it? [00:19:21] Daniel Rath: When you talk about soil metagenomics, in a teaspoon of soil, I'm sure you've heard the statistics somewhere, right? In a teaspoon of soil, there's like a billion microbes and like so much fungal hyphae. And inside each one of those cells is DNA. That are basically the instructions for life for those different cells. [00:19:40] What we do in soil metagenomics is that you extract the DNA from a soil sample. And then the most complex, insane puzzle you've ever seen. We try to reassemble them, right? Right. And so like that is only possible because of the advances we've made in computing over the last few decades. And I get, you know, the national labs have really like pushes forward. [00:20:03] You need a really powerful supercomputer to do it. Once you've done that, you have this sort of unprecedented ability to glimpse what is happening in the soil at a scale that we've never been able to before. And so that's part of the reason that people are really excited about it is because it gives us a window into like this. [00:20:24] previously unknown black box of how microbes work and interact in the soil. I worked on that during my PhD at UC Davis, looking at like how metagenomes changed in farming systems over 25 years. [00:20:37] Craig Macmillan: So I have always been looking for the work that I do, looking for what are the variables that I can measure and what's going to give me a number that's going to tell me what's going on. [00:20:46] At one point I hit upon soil respiration, and I was talking to a soil ecologist and she said, well that's fine, but that tells you how much life is there, but it doesn't tell you whether it's good guys or bad guys. And then dove in to a whole nother level of, Oh yeah, I hadn't thought about, oh yeah, you're right. [00:21:05] Oh, and then those guys prey on those guys, and then this happens over here. Oh wow, yeah, you're right. And then I got kind of hooked on the um, The Haney test, which is, I think, kind of falling out of fashion now, which again, people were throwing rocks at that, you know, and I think that when Haney first came up with that, that was something, it was like, we need something, and it would prove to be useful, I think, but I don't think that's as popular or gives us the kind of dimension that we really need anymore, at least that's what I'm told. [00:21:34] With metagenomics, we're going to be able to tell not simply quantities, but we're going to be able to tell possibly down to the level of genus, maybe even species of who's, who's down there, which could be really, really important because like pseudomonas, for instance, there's certain pseudomonas that are, um, pathogenic and there's others that are beneficial. [00:21:56] And so we kind of need to figure out who's who and what's what is, is that on the horizon? Maybe it's 10 years out or more, but is that on the horizon? [00:22:04] Daniel Rath: Probably a little further out than that. A [00:22:06] Craig Macmillan: little further out? Okay. [00:22:07] Daniel Rath: I'll try and give you an example here. So, one of the things that we get when we pull out all this DNA is we get sort of relative abundances of different types of organisms, right? [00:22:18] It's sometimes quite difficult to get to the absolute abundance of organisms because We're really looking at, like, proportions of DNA, but that doesn't really tell you, like, are there, like, massive amounts of this organism present in the soil. You just have a relative idea. When it comes to metagenomics, there's a lot of promise in being able to say, Oh, look, we've seen these genes that, like, allow you to fix nitrogen. [00:22:43] And we found these genes that are associated with these, like, pests. And that's a really good idea, a really good indicator of, like, But there's another level to it. And that's really, I think what one of the like exciting parts is, is that it's not just the genetic potential that matters. It's the interactions between organisms that is quite hard to pull out. [00:23:05] So to your example, you could have pseudomonas, you could have quite high levels of pseudomonas. Do you have a. predator that keeps those pseudomonas populations under control, right? Because if you do, then you might not be seeing a lot of disease, like presence in the soil, even though you have like relatively high amounts of it. [00:23:25] And so understanding these interactions is sort of the next level in actually getting practical, actionable information out of these metagenomes. And we're, we're still. Teasing that apart. So really, when I talk about metagenomes, it's about potential. What is the potential for things to happen? But it does not actually mean that is what is going to happen. [00:23:46] Craig Macmillan: Right, exactly. And so the commercialization of this technology is quite a ways out. [00:23:51] Daniel Rath: Yeah. I mean, there are companies that are working on it right now. Again, this, it's a, this innovation is really, we're going to need to like be iterating towards success here, but really a lot more sort of research and work is required, especially on these interactions, thinking about like how they fit together. [00:24:10] And I personally think that it's a useful indicator. I've given a talk on these like. Soil test before the real power hard part comes when you're trying to interpret right when you have a scale that says like based on these abundances There's X percent chance that you will have a disease or X percent chance that you will be able to cycle nitrogen better That's really hard to like say at this point in my opinion, [00:24:35] Craig Macmillan: right? [00:24:35] Right. Well, at least we're moving in the right direction. I think [00:24:37] Daniel Rath: we absolutely are and honestly The, the best thing to compare metagenome test is your own soil five years ago. It gives you an unprecedented look into how your soil has changed and progressed depending on whatever practices you've applied. [00:24:51] Craig Macmillan: Right, right. Going back to regenerative agriculture, is there one thing, piece of advice, idea, one thing that you would like growers to take away on this topic? [00:25:02] Daniel Rath: Yeah, I think that one main thing is that this is not just about one specific environmental impact. This is about thinking about how we farm, how we grow food, what is our relationship To both farm ecosystems and agricultural ecosystems. [00:25:21] You know, I think there's this idea that natural ecosystems and agricultural ecosystems, they cannot coexist. And I think that over time we're starting to see that maybe that's not true. We can encourage biodiversity. We can encourage sort of these complex natural processes on farms. And indeed they make the farms more resilient. [00:25:41] more productive, we get more benefits from that. And so just in a way that like natural ecosystems evolve, I think that farming systems are also evolving and growing. And to us, regenerative agriculture is about bringing all farmers, no matter where they are, along on this journey towards sort of more sustainable, environmentally safe agro ecosystems. [00:26:05] Craig Macmillan: That's exactly the word I was going to use, is uh, is we think more about an agroecosystem as part of a much larger system, um, which is what ecology is kind of all about. We can look at the ecology of a pond, but then we can also look at what role that pond plays in the forest, and we can look at how the forest plays in the landscape and we can just keep going depending on what level you want to do it at. [00:26:27] And I think looking at our farms as part of a larger ecological system and an ecological system in and of itself also I think is a huge philosophical move. Absolutely right. Where can people find out more about you? [00:26:39] Daniel Rath: The NRDC website is a great place to start. We have a number of different resources. We published a report on regenerative agriculture where we interviewed farmers from across the U S at least for California specific stuff. [00:26:50] The California department of food and agriculture, again, is, has this regenerative agriculture definition process that's being carried out. As of this date in August, 2024, I also have a personal website that I update infrequently. [00:27:04] Craig Macmillan: Well, there's something on there. Yeah. So, yeah, and if you can share those links with us, that would be fantastic. [00:27:10] Our guest today has been Daniel Rath. He is a soil scientist with the Natural Resources Defense Council. Thanks for being on the podcast, Daniel. [00:27:18] Daniel Rath: Hey, absolutely. It's been quite a pleasure, Craig.   Nearly perfect transcription by Descript

[00:00:00] Beth Vukmanic: Have you ever. Wondered do third-party certifications matter to consumers? [00:00:05] Welcome to marketing tip Monday with SIP Certified. We know that consumers are looking for wines labeled as sustainable. While our longer form episodes help you learn about the latest science. And research for the wine industry, these twice monthly micro podcasts. will help you share your dedication to sustainable winegrowing. [00:00:24] If you've wondered about third-party. Certifications. You're not alone. This question has. I also crossed the university of Portland's Sam Holloway's mind. In this week's marketing tip learn about Holloway's qualitative. Research findings. And what they mean for your sustainable wine brand. [00:00:40] Holloway was interested in learning. How supply chain certifications are perceived by consumers. Impact purchasing decisions. And impact brand loyalty. In interviews and focus group discussions, his participants revealed that they were more likely to trust products bearing. Recognized certifications. [00:01:00] They viewed certified products as offering a higher value. And they were more willing to pay a premium for certified products. After coding and analyzing participant transcripts Holloway notes, that certifications quote. Enhanced brand loyalty by aligning with consumers ethical values. And beliefs. End quote. [00:01:20] While, certified products were associated with increased. Brand loyalty. Holloway's participants noted that lack of transparency could lead to skepticism. And diminished trust in brands with. Certifications. But there's an easy solution. transparency and clear communication remedy these issues before they arise. [00:01:39] Holloway's participants also emphasized stringent standards and third party verification as important factors. That enhanced their trust. [00:01:48] By sharing your story, you can connect with your guests over shared values. And spread awareness of sustainable wine operations like yours, that work. To protect the people and the planet. [00:01:58] And if your SIP Certified. You can add the SIP Certified logo to your wine labels for any wine made with at least 85% SIP. Certified fruit, whether that's estate or purchased. Check out the links in the show notes. To get your wine certified today. [00:02:13] Until next time, this is sustainable. Winegrowing with the vineyard team.   Nearly perfect transcript by Descript. Resources: *** Tell Your Sustainable Story Online Course *** Apply for SIP Certified Wine Join ReSIProcal February 2025 Marketing Tips eNewsletter Sustainable Story | Print Sustainable Story | Electronic What's your Sustainable Story? Vineyard Team Programs: Juan Nevarez Memorial Scholarship - Donate SIP Certified – Show your care for the people and planet  Sustainable Ag Expo – The premiere winegrowing event of the year Sustainable Winegrowing On-Demand (Western SARE) – Learn at your own pace Vineyard Team – Become a Member