Fermentation, Pt 3 — Is using yeast cheating? And who decides?

James Harper (Filter Stories narration): This is Filter Stories. I'm James Harper, and we've arrived at the end of the episode on fermentation in the series The Coffee Producer Toolkit, in collaboration with Lucia Solís, that tries to help coffee farmers have more profitable, sustainable businesses.

And hopefully already, you are finding this series very helpful in your coffee journey, helping you understand the reality for coffee farmers. This information is going to help the rest of your coffee journey. If you haven't heard the last two episodes, I highly recommend you check those out before you listen to this,

So, in this next section, we talk about what commercial microbes cost. And the figure we put out is 30 cents per kilo. And I want to take a moment here to contextualise that number. Because the number by itself, you know, 30 cents per kilo, doesn't sound like very much. But for a coffee producer, that is significant.

Now, you remember that using commercial microbes, like we showed you in the last episode, more than anything else is ensuring that fermentations are the same batch to batch. So a lot of producers initially are going to see this as a cost and not an increase in their profit. And I want to show you why that cost, you know, for a very small producer is really unsustainable, but it's much more manageable for a larger producer. And of course, for investments like these to make sense, it all comes down to the price the farmer receives.

So let's start there. Where the price the farmer receives is very low, 30 cents per kilo will lower their profit margin. In 2019, in the depth of the coffee price crisis, where coffee got as low as $2 per kilo, adding 30 cents to the production cost is out of the question. Many producers who had to survive on that were already probably making a loss.

Now, in more recent years, the coffee price has been higher. And when coffee's maybe six, seven, eight dollars per kilo, 30 cents per kilo seems more manageable. But there are some nuances here. Let's take a small scale farmer in Colombia, right? At a time of relatively high coffee prices. If they were to increase their production costs by 30 cents a kilo, they could be looking at a decline in their take-home pay — very roughly, because there's a lot of factors at play — maybe five to 10% in their take-home pay. Now, if a farmer is small, a five to 10% reduction in take-home pay is really significant. Because at that level of income, right — let's say, hypothetically, that they were earning $2,000 a year, and now they're earning $1,800 a year, right? A 10% reduction. It hits so much harder when you're earning those sums of money, because at that level of income you are forced to make some very hard trade-offs. Can I afford a pair of school shoes for my kids? That is a horrible choice for a farmer to be forced to make.

Now, for a producer who earns a lot more, they're on a bigger farm, a 10% reduction in their income from $20,000 down to $18,000 — the stakes are much lower. It's not “can I afford school shoes this year?”, it's "can we afford to take that holiday we were planning, to the capital?” The stakes rise sharply as farms get smaller.

So practically speaking, who is going to be able to afford commercial microbes? Well, for the most part, larger, wealthier producers. Now, when it comes to smaller producers, maybe there's a case for using commercial microbes. Maybe they can justify the investment, but only if they're earning very good premiums, significantly above the commodity price — if they're selling to a buyer who's prepared to pay higher premiums over the commodity price. For example, The Coffee Quest in Colombia. But those opportunities for smaller producers are quite rare.

So all this to say: the producers who are most likely to adopt commercial microbes first are going to be larger producers. And maybe, in some special circumstances, smaller producers who have access to buyers paying big premiums.

Okay, so that's the context. Pressing play.

James Harper: All right, Lucia, let's talk investment sums.

We've explored lots of ways you can increase your profitability using commercial microbes, but critically it matters what they cost. Is the payoff worth the investment?

Lucia Solis: Yeah, the cost objection is not true. The cost of a... we'll add about 30 cents.

James Harper: Okay, so when it comes to return on investment, how should a producer think about it?

Lucia Solis: The most compelling reason to use commercial strains is as insurance. And insurance is something that you only fully value when you don't have it and something goes wrong. So when you have a rejected container, or a defective lot, or you've lost a buyer — yes, those are rare, But when they happen, the financial damage is incredibly severe. And if you, at that point, went to somebody and said, "Hey, for 30 cents a kilo, you could have completely avoided this," I think it'd be a no-brainer. Everyone would take that bet.

James Harper: Now, producers might be wondering to themselves: "Could I just get yeast cheaper somewhere else?" You could walk into any grocery store and pick up baker's yeast, which is a lot cheaper than 30 cents per kilo. So can producers just use cheap bread yeast instead?

Lucia Solis: Yeah, I've — I've seen this too, so this isn't theoretical. I can tell you from experience, other producers that have used it, and I have used bread yeast as well as an example for producers in my training courses of what not to do.

And this is because baker's yeast is optimised for warm, oxygenated dough with different kinds of sugars. And a coffee fermentation tank is really acidic, it's anaerobic, and the sugar chemistry is completely different. So, it's a fruit, right? Yeah. We have the glucose and the fructose, and when you have bread or beer made out of wheat or barley, those are different sugars than from your fruit sugar. So if you're trying to use the same yeast, it's like trying to give a vegetarian a big steak to eat. It's not going to do well in their digestion.

If you use a bread yeast or a beer yeast, it won't perform as well. And the flavour compounds that it produces are not the ones that you want in your cup. So when we're talking about fruity and acidity and, like, these bright, lively notes — not only is it unlikely that you will get those flavours, a lot of times from those conditions of the yeast being in an unfamiliar environment, it will create stress compounds instead. And so I've tasted a lot of coffees made with beer yeast that taste like cheese, that are like stress. The way, you Know, a human when we're sweating can smell like body odour, or kind of that stinky aroma — yeast do that too. When yeast are stressed, they create sulphur compounds, just like we do. And those can come out in your cup.

James Harper: Right, so no, you can't just use cheap baker's yeast.

Okay, so let's say we use what we should be using — for example, Novonesis microbes made specifically for coffee, Pichia and Lactobacillus plantarum, link in the show notes. I'm a producer, I've just done a fermentation. I now have a barrel swimming in Pichia or Lactobacillus plantarum. Billions of them. Couldn't I just scoop out some of that and use it to inoculate a fresh batch? They would just multiply on their own, and that would save me having to spend 30 cents per kilo every time, because it's basically free.

Lucia Solis: Yeah, James, what you're talking about is back slopping. You could absolutely do that. You can do whatever you want to do.

James Harper (Filter Stories narration): Yes, but to be clear, Novonesis recommends you don't backslop.

Helen Riley (Novonesis): We would steer away from backslop dosing.

Lucia Solis: And maybe cynically you would think, well, of course the company wouldn't want to recommend reusing their yeast because it would cut into their profits. But there's actually a really good reason that you don't want to do this.

If the goal of using commercial strains is consistency for your customers, then using this back slopping method is a challenge. The problem is that those microbes are not staying the same.

James Harper: Right, and when we were at Novonesis we spoke with Gunna Øregaard, one of their senior microbiologists. He explained how microbes can divide and grow incredibly fast.

Gunna Øregaard (Novonesis): It's two, it's four, it's eight, it's 16, and suddenly you have a million. [...] Maybe there are two or three of those nucleotides that change every time they divide.

Lucia Solis: And while most of those differences can be insignificant, sometimes they're not.

James Harper: Right, so basically at the end of the fermentation the microbes are not genetically the same anymore, You originally added that microbe because it would produce a certain flavour. But now it's mutated, evolved during the fermentation. It might not behave the same way that the original strain did. It may not produce the same flavours.

But now, let's look at a real example of someone who does do backslopping and what they see. Fridolin in Zambia — he does backslop between fermentations, and he explained to us he sees the difference between the original fermentation using fresh commercial yeast and the backslopped second fermentation that followed.

Fridolin Stocker: We didn't have any backslopping lots which were, uh, totally different in the flavour. But we saw that the intensity differed a bit.

James Harper: And, generally, he was apprehensive.

Fridolin Stocker: Consistency, as previously said, is very important. And backslopping is definitely a risk to that.

James Harper: Because at his scale, he ferments an entire container of coffee at a time. So if there was a problem in the first fermentation and you backslop, you carry that problem across into the second — and then suddenly, the amount of problematic coffee has doubled.

Lucia Solis: Coming up next, we address the most common concerns producers raise when they're considering using commercial microbes.

James Harper (Filter Stories narration): Pressing pause. In this next section, we address three questions, but I want to give you some context on two particularly thorny ones that producers are going to confront if they choose to use commercial microbes. Is using commercial microbes the same as adulterating the coffee? And should a producer tell their buyer that they're using commercial microbes? So hopefully by now it's clear to you that using a commercial microbe is not the same as adulterating a coffee. This question comes up because we are now in the world of co-ferments. It's become a bit of a trend where some producers, they might add, for example, fruit to the fermentation tank — strawberries — and the coffee's coming out will have a distinctly different flavour. Some a bit more strawberry-like. These co-ferments are hugely controversial in the coffee world. Some roasters really prize it for the novelty of coffee flavours. Other roasters really hate it. It goes against their notion of what a quality coffee is. For them, the way they've defined it, quality is when the plant's genetics meets the terroir and the farmer's guiding hand, all coming together to produce a quality coffee. In their minds, if the story is "oh, this coffee tastes the way it does because they just put strawberries in the fermentation” — well, that's a much less romantic story.

Now, hopefully, as we've already established, using commercial cultures is not the same as adulterating your coffee, It is not the same as a co-ferment, or adding some kind of essential oil flavouring to the coffee. Microbes are going to proliferate anyway in the fermentation; using commercial microbes just controls which ones dominate. The microbes themselves taste pretty neutral, but when you use the right ones, the byproducts of these microbes can taste pretty good.

Nevertheless, in this environment we are in, where everybody is questioning what quality is — and is adding fruit to the fermentation, is that still a quality coffee? — you can understand how a producer might be apprehensive about using a commercial microbe,

The wider point is this. There is a massive power imbalance in the coffee industry. Coffee buyers, roasters, define quality, and they have a lot of power because they are the ones who buy coffee. But when you contrast it to the wine world, this is very strange. In the wine world, a winemaker, they produce what they think is a quality product. And then buyers come to them being convinced that this winemaker is the expert of their product and the winemaker knows what quality is.

Lucia and I really hate the fact that producers don't have power to set the terms of quality for themselves. We think they should. They are the experts in their own production. If they want long-term sustainable businesses, they need to be the ones who set the terms for quality so they can get the higher premiums. But on the other hand, you have roasters who, again, hold the purse strings. If they don't want to buy a coffee because it doesn't meet their definition of quality, then they're not going to buy the coffee. And that's a commercial loss for a producer. There is a tension there,

And in that environment, especially with co-ferments and adulterated coffees floating around, there is a bit of an air of suspicion between producer and buyers at the moment. Is this coffee that I am tasting from this farm — these flavours are amazing, they're really unique — but did they actually just co-ferment it with strawberries and not tell me?

Now, in the case of strawberries, I think we can all agree that a producer should disclose that, if that's what they used. But when it comes to yeast, Lucia's position is producers should have no obligation to say anything if they don't want to. Commercial microbes are not adulterants. Because in the wine world, you know, we don't ask the winemakers, "Hey, what commercial microbes did you use in this wine?" Nobody does. The proof is in the wine. Do you like the wine? Do you consider this a great wine or not? End of story. Ideally, it should be the same in coffee.

But it's also true that producers have very little power in this dynamic. And so if a buyer asks for this information and a producer doesn't volunteer it, well, you know, the roaster might think, hmm, they're trying to hide something. And so that's why in this next section Lucia and I tread this very fine line, where we say: look, you can disclose if you want that you use commercial microbes. But if you don't want to, don't feel obligated either.

We would like coffee producers to be the owners of their quality — for quality not to be defined by buyers, mostly in the global North. Which, by the way, historically was not the case. I made a whole three-part series on that, link in the show notes. Like I mentioned, for producers to have long-term sustainable businesses, it will tremendously help them if they can own and define quality on their own terms. And that's what we advocate here.

And now I'm about to press play, but also this is the last section of this episode. So I'm now just going to let the rest of this episode play out to the end. I hope you've enjoyed this and I look forward to speaking to you in the next episode. All right, pressing play.

James Harper: We're going to cover three common questions and concerns producers raise when it comes to using commercial microbes.

Lucia Solis: The first: should we be concerned about its environmental impact?

James Harper: Second: using commercial microbes, is that the same as adulterating my coffee?

Lucia Solis: And third: when talking to buyers, how do I talk about the use of commercial microbes?

James Harper: So let's address the environmental concerns around using commercial microbes. Some producers are worried that once their fermentation is finished, all that wastewater, you know, now full of these commercial microbes, gets drained out and it makes its way through the wastewater system and eventually ends up in nearby rivers and back on the land. And the concern is: should we really be introducing all these foreign microbes into the surrounding environment?

Lucia Solis: Yeah, James, when you put it like that, I can see how that can seem really scary.

James Harper (Filter Stories narration): But Lucia, you've seen the studies, right, that show that we have nothing to worry about.

Lucia Solis: Scientists have actually answered this question already for other industries. And what they have found is that these selected strains thrive under very specific conditions. These are not terminator strains designed to be indestructible.

With Saccharomyces cerevisiae, studies have been done where huge concentrations of these microbes were sprayed directly into the vineyard. The worst-case scenario: just opened up these bags and sprayed them directly onto the grapes, the leaves, you know, the trunk of the plant, the soil, kind of everywhere, just to see what would happen in these really high concentrations, So they were coming back every couple of weeks, over several months — I think it was a full three years — that they kept coming back to see how are these microbes surviving over time and how far are they spreading.

And their conclusion was that actually very few of them survived. Very few of them were able to survive out in this environment, because they're not adapted well to survive out in these environments.

James Harper: Right, so these microbes just die off. It's not like they take over at all.

Lucia Solis: You know, James, something that I think might help our audience kind of wrap their head around this is the analogy that I sometimes like to use: dogs. When people are unfamiliar with commercial strains, sometimes they can think of them as, you know, these fierce, competitive creatures, But I like to think of them like labradoodles, you know, the cute fluffy dogs.

So imagine if you put a labradoodle out in the wild with coyotes and mountain lions and wild boar and bears and who knows what else. Well, our sweet little labradoodle is probably not going to survive for very long. So along those veins, commercial microbes have been selected to thrive in very specific fermentation conditions. And when out in the wild, outside of the fermentation tank, they actually don't do as well as the wild microbes, as the local microbes that have evolved and adapted to those specific locations.

And if you're listening and this is interesting to you, if you're a microbiology nerd, I did a whole episode on Making Coffee, going really deep into this study and about how wineries use these microbes.

James Harper: Link in the show notes. I also think it's worth mentioning that these commercial microbes, they're not genetically modified either. You know, they're not like that. They were taken from natural environments.

Gunna Øregaard (Novonesis): All our bacteria originate from nature, either from plants or animals or fermented food products. They are all natural.

James Harper: The team at Novonesis mentioned that, you know, they sometimes send their staff out to collect microbes from the surrounding environment.

Gunna Øregaard (Novonesis): Two years ago, we asked our colleagues at the company: could you all please come up and pick up — they were small tubes. And then if you have your own garden, you could sample one of those plants and provide them to us. And then we would isolate them.

James Harper: Can you imagine? Thousands of staff heading into gardens just to find these new microbial strains that they can then bring back to the lab. From there, they figure out which ones might work for cheese or coffee or whatever. And then, just like humans have been selectively breeding crops for thousands of years, they do the same with bacteria. They call it improving the microbes. Gunna Øregaard (Novonesis): When we talk about improving strains, we use methods that are non-GMO.

Lucia Solis: They select for traits that make these microbes better at specific tasks, like fermenting coffee. And coffee is fermented at a very specific temperature, so they're looking for microbes that can handle the environments that coffee is usually found in. And once they've got this microbe that performs really well, they'll freeze it, and they can grow it over and over again in the future.

James Harper: So we don't have to worry about these microbes being in the environment because they came from the environment. And actually, the two strains that Novonesis produce specifically for coffee already are on coffee farms. You can find them already there on most coffee farms.

Lucia Solis: Yeah, you know, James, Lactobacillus and Pichia are found on coffee already, but in very small amounts and with a lot of other wild microbes. So what we're able to do is take the microbes that are already found in coffee and just amplify them, have them in larger volumes so that they can control our fermentations.

James Harper: Right, so even with a wild fermentation, the two microbes that you could get commercially are already in a wild fermentation.

Lucia Solis: Yeah, absolutely. So it's hard to notice those effects.

James Harper: Mm-hmm.

Lucia Solis: James, before we move on from this point, I want to be really clear about something that bothers me, and that's the fear-mongering around the environmental dangers of using commercial strains. I want to say that it's exaggerated and it's also not supported by science.

This moral panic around using commercial strains distracts from the real environmental threat, which is unmanaged wastewater. So there is damage to the environment. It's coming from the sheer amount of untreated toxic wastewater that finds its way into the rivers, the lakes and the community water supplies. So this is where our attention really needs to be.

And just in case you skipped it in the previous episode, we covered suggestions on how to reduce your use of water and then how to treat the water that you do use. So we highly suggest you go back if you're listening out of order.

James Harper: Okay, so now let's turn to the second concern producers raise about using commercial microbes, And that is: if we use a commercial microbe, isn't that the same thing as infusing the coffee with a specific flavour? Like putting grapefruits into the fermentation tank? Or adding vanilla essence? Or some kind of artificial flavouring?

And this, of course, was a major controversy at the Best of Panama coffee auction. Organisers tried to ban any kind of infusion. And they lumped commercial microbes into that ban alongside fruits and essential oils. Franz Zeimetz, the Panamanian CEO of Lost Origin Coffee Lab, told us about the fallout. His business is buying top-tier coffee cherries from Panamanian producers, Prized Geishas that sell for hundreds of dollars a kilo. And he ferments them very carefully. And he says that after the Best of Panama ruling, a lot of producers pulled back from using commercial microbes.

Franz Zeimetz: Yeah, in general, in Panama, I think everyone either stopped using yeast, or if they do use commercial cultures, won't be advertising that as much. I think in 2022 people were using a lot of it. You had big farms that were consuming all kinds of yeast. Now, all the big farms have stepped away from that.

Lucia Solis: And because infusions and microbial inoculations both involve adding something external to a fermentation, these two things have been conflated. But I really want to be clear that they are not the same thing.

An infusion would be anything that adds external flavour compounds to the coffee, So adding cinnamon, adding essential oils of any kind, orange essential oils, or adding, you know, petals, like jasmine petals, during the coffee's drying to try and get the jasmine flavour into the coffee. That is adding flavour compounds to the coffee. You want that one-to-one translation.

But a starter culture is different. A starter culture is adding living organisms that do what microbes have always done. The microbes are eating the sugars. They're producing the acids and the flavours and the alcohols in a controlled and predictable way.

And I think one big thing to kind of get different in your mind is: if you add strawberries to the tank, most producers are hoping to get the flavour of strawberries. But if you're adding yeast or bacteria to the tank, you don't want bacteria-tasting coffee. You want the products of that bacteria. So that's a way that you can think about the intention of what we're adding. Because the fermentation process, that is unchanged. And I actually made an entire podcast episode criticising the Best of Panama organisers for putting commercial microbes on that list and treating them as the equivalent of other infusion products like fruits or essential oils. You can find a link to that in the show notes.

James Harper: And so, commercial microbes and adulterants are clearly not the same thing. But this now takes us to the third concern producers sometimes raise. Because even if you agree with us, there might be some buyers out there who don't see that distinction. And that puts you in a difficult position as a producer. If you are using commercial microbes, what do you tell your buyers?

Lucia Solis: I think that you should disclose whatever you feel comfortable disclosing. But I —I think that a lot of times in our culture, if you don't say something, it's kind of equated to hiding something. And I think none of what these commercial microbes are doing, or the flavours that they are creating in coffee, the complexity that we get to create in coffee, is anything that needs to be hidden or that we should be ashamed of.

So I recommend that if you get questions, you should definitely share whatever you feel comfortable sharing. Tell people what you're doing, because there's nothing to be ashamed of. There's nothing wrong, there's nothing cheating. This is just another industry doing what others have done for decades — we're just the last one.

James Harper: Yes, and all the producers we spoke to about commercial microbes, they are very upfront with their buyers. For example, Alejandra Rodríguez Delgado and Gustavo Arroyo, Puerto Rican producers, told us —

Alejandra Rodríguez Delgado: Eh, si es levadura comercial, es levadura comercial, lo escribo. Este... pero explico: el café ya tiene levadura, lo que estamos haciendo es aumentando una población. [If it's commercial yeast, it's commercial yeast — I write it down. But I explain: the coffee already has yeast; what we're doing is increasing a population.]

Gustavo Arroyo: Si, hemos sido... hemos tratado de ser lo mas transparentes posible. [Yes, we've been... we've tried to be as transparent as possible. ]

James Harper: They make it clear to their buyers: look, coffee when it ferments already has yeast in it. What we're doing is just increasing its population.

And for Franz Zeimetz, his approach is to be fully transparent.

Franz Zeimetz: Some people don't care about your inoculations. Other markets, they're going to be super geeky about it. They'll want to know exactly what yeast you use, exactly what bacteria you use, fermentation time, fermentation temperature. So for us, it's just being as transparent as possible, and then letting the buyer portray that information, or filter that information, to their clients in the best way possible.

Lucia Solis: Producers, if you feel like saying nothing, you don't need to. Specialty coffee really wants to compare itself to wine, but not a single buyer has ever made a purchasing decision based on what yeast the winemaker used to ferment the grapes. When you buy cheese or yoghurt, do you know what bacteria was used to ferment that? I promise you, it was a commercial strain. When you buy bread at the bakery, do they tell you what yeast they used?

We hold coffee producers to a different standard than every other fermented food. All of those other producers don't feel like they need to disclose whatever yeast or microbes they use in their fermentations, and I don't think coffee producers need to either.

James Harper: Lucia, let's quickly recap what we want producers to walk away from with this episode.

Lucia Solis: First, your coffee is going to ferment whether you want it to or not. So the choice was never ferment or don't ferment. The choice is whether you control it or whether you play nature's lottery.

James Harper: Second, commercial microbes are not some kind of magic dust. If your fundamentals aren't there, a microbe won't give you great quality coffee. Get the basics right first, then reach for commercial microbes.

Lucia Solis: Third, think of commercial microbes as insurance. And the value of insurance is something you only really understand the time you don't have it.

James Harper: Fourth. There are many ways commercial microbes can make your farm more profitable, They enable consistent fermentations batch after batch. They enable long fermentations that you can run safely without a wild yeast wandering in at the 30-hour mark and ruining it. Commercial microbes have the potential to lift the quality of your lowest-quality cherries. Commercial microbes can also clear a bottleneck in your wet mill. And commercial microbes contribute to your coffee having a longer shelf life.

Lucia Solis: Fifth, and I want to be really clear about this: a good microbe cannot compensate for bad process. Guys, clean your tanks after every single use, stay away from chlorinated water, no scented soaps, get a pH meter and a thermometer — they are going to be your eyes inside of the fermentation — take readings at least twice a day, write it down, and cup the results. Because without that feedback loop, you cannot improve.

James Harper: Sixth. Don't blindly copy someone else's fermentation recipe. What works in Victor's barrels in Colombia may not work on your farm. Don't reach for the baker's yeast at the grocery store. I know it's cheaper, but it's the wrong tool for the job. And it's going to taste like it. And be careful about back slopping, It's cheaper, but you are gambling with consistency.

Lucia Solis: Seventh, on the environment. Research suggests commercial strains are not an environmental concern. The real environmental threat at your mill is the untreated wastewater.

James Harper: And finally, using a starter culture is not the same thing as infusing your coffee with strawberries or essential oils. They directly add a flavour. Commercial microbes reveal the coffee's flavour potential. They don't add flavours.

Lucia Solis: And when it comes to what to tell your buyers, how to talk about microbes: share whatever information you're comfortable sharing. There is nothing to be ashamed of and there's nothing to hide. But also remember that no one asks their baker what yeast they use. No one's going around checking their yoghurt to see what microbes are in their yoghurt. Coffee producers are being held to a standard that no other fermented food is held to.

James Harper: So you can use commercial microbes to differentiate yourself to your buyers, or you can use it privately and just say nothing. Both are great.

Coming up in the next episode of the Coffee Producer Toolkit, we help you find coffee buyers.

Lucia Solis: Thanks for hanging out with us on this third episode of the Coffee Producer Toolkit.

James Harper: If you found that useful, please share it, pass it along, spread the word. It's just Lucia and I making this series, we really rely on you to get the word out. In the show notes we have linked everything we spoke about in this episode: the microbes, the equipment. There is a stack of practical resources to help you run your own fermentation trials.

Lucia Solis: And if you wanna go deeper on any of this, I've covered a lot of these topics on my own podcast, Making Coffee with Lucia Solis. There's an episode on the research into whether commercial microbe strains survive out in the environment, and one where I take apart the Best of Panama decision to treat starter cultures as infusions. I'm also sharing a lot of videos on YouTube so that you can see my fermentation tanks, the size that I do my fermentations, and all of the things that go into the coffee that I make on my YouTube channel.

James Harper: And Lucia, of course, people can come visit you to learn how to do fermentation.

Lucia Solis: Ah, that's right, James. Thanks for reminding me. I do host fermentation training camps, two or three per year, mostly in Guatemala, but the next one is in Kenya, and that's where you can come with me in person. We have a lot of these microbes, and you can learn what they should look like, how to rehydrate them, everything that you need to know to do a very successful fermentation yourself.

James Harper: My podcast has not covered fermentation in any way yet, but I have covered how you can navigate tricky conversations with buyers. And one thing that you might find very helpful in navigating this conversation is really understanding where this notion of coffee quality came from. I've linked an episode in the show notes.

Lucia Solis: You can find us both on Instagram: at Lucia Solis, and James, at Filter Stories Podcast.

James Harper: But really, the better way to keep up with our work is to subscribe to our newsletters, link in the show notes.

Lucia Solis: This series of the Coffee Producer Toolkit was produced by me, Lucia Solis, Nick Hafner and James Harper. James also wrote and played the piano music.

James Harper: Thanks for listening. See you next time.

Lucia Solis: Gracias por su tiempo, y hablamos en el próximo episodio.

[Thank you for your time, and we'll speak in the next episode.]