Update and the Science of Matcha whisking

 

 

Ryan Ahn (00:00)
Hello and welcome to the Specialty Matcha podcast. My name is Ryan. This is my co-host Zongjun. Hello, hello. Who also goes by Sam and we're the co-founders of Sanko Matcha products. We launched this podcast to discuss our learning journey in Matcha share startup stories and interview experts. And today we're doing a very mini update. We've been very busy this week and didn't have time to completely edit a podcast episode. So we wanted to repost

One of our favorites, was the second one we ever recorded, the science of matcha whisking. So, Dongjun, do want to give a little update on what we've been working on? Yeah, so we've been working on the mills for... This is already like a year full. Nine months, I think. Nine months. mill to mill matcha fresh, anywhere and everywhere. Yeah, so...

we spent a lot of time trying to get the output to meet the same standard as a traditional Ishii yuzu in terms of the powder grind, powder fineness and the flavor. So right now we are getting pretty close in terms of the flavor and the granularity of the matcha powder. Yeah, we're really at the point where like

We would be proud to serve this to anyone. it actually tastes pretty good. But the only problem is it's incredibly slow. We're still trying to increase the motor speed. But that means the motor is going to generate significantly more heat. So we're actually installing a cooling system.

to cool the matcha down so that it won't essentially cook the matcha and it won't taste good again. Yeah, all these variables are fighting each other. If you want speed, you generate heat. If you want fine particles, you need more pressure. Have more pressure, you get more heat and you need more power. It's really a vicious cycle fighting against each other. And I think we've gone through the cycle now three or four times of just like upgrading the motor.

and beefing up the cooling system. But it's really tasting good and we keep comparing it to benchmarks. And another thing that I think people listening to this might be generally interested in is very few people have the opportunity to taste matcha on the day one of shelf life, like right after it was milled and taste the transformation. So we've been tasting it from day zero and through about a one week cycle every day. And the flavor transformations are

It's drastic. Incredible. They're very different products actually almost every day. Honestly, even after the powder gets milled and you know, gets set for a couple hours, it starts to change. Yeah. It tastes very different. And that arc is pretty different when we run Okumidori through it or if we run Samidori or if we run through something like Yabukita. These degradation, I don't even want to call them degradation because it's...

Even one week, it transforms actually even after one week, tastes still pretty good. ⁓ but it tastes very different and they go through these kinds of different cycles. ⁓ especially around creaminess, especially around astringency and bitterness in particular, those variables really change. Honestly, they all taste very good in their different time interval. ⁓ I personally really like when it's really just fresh out of the mill.

I it has a very interesting, I think we've milled a Samidori and it has a very interesting like floral, like white flower notes that I really have never experienced in other Samidori. So that's a very interesting characteristic and that flavor just disappeared. It's a totally different matcha. We had a very similar experience with Marukyu's higher end matcha blend.

Ten it's called tenju tenju. It's called tenju where it had this beautiful like high-end olive oil note that disappeared one day later It's this stuff is extremely fragile, but it's really interesting tasting those differences And kind of understanding the different granularities of matcha turns out you really really want clumps when matcha comes out of our machine and it's acting like sand it

it, we know that we have not applied enough pressure. But now it's like floating around everywhere. Like it's producing these chunks that attach to the ceiling of the machine where it's just so fluffy and so fine. It's like snowflakes. When it comes out of the machine, it kind of snows out, which makes a gigantic mess, which is another problem we need to solve. But that's when we really

knew that we were milling to a fine enough granularity. Happy headache. Happy headache. Happy headache. Good headache. But milling matcha is a mess. So that's our mini update. We are going to now link to the episode, The Science of Matcha Whisking, which is one of our favorites. If you haven't listened to it, please enjoy.

If you have listened to it, we do have a mini update. We've actually learned some things that probably should have been included in that episode that we just didn't know at the time. big thank you to Ian from You Know Me, who sent me a research paper who told me that matcha foam stability and matcha foaming agents are actually more than just surfactants, primarily a compound called T-saponins, but also pectin.

When you mill matcha in these natural plant tissues, you actually get quite a bit of pectin, which really helps foam stability. And there was a research study, I believe it was when you removed the pectin, you lost a lot of foam stability, or if you added more, it in conjunction with the surfactants, added the foam stability. So that was a detail that was missed in the previous recording. Do you know the degradation rate of surfactants and pectin?

being different or about the same? I have no idea. bet pectin is relatively stable, but for surfactants like T-saponins, and I have no idea. It's a good question. I don't know. we can look into it. And I bet the finer the matcha particle size, like the finer you mill it, you get more like free pectin floating around because you've really broken down those plant tissues.

The other thing that I was researching that belonged in this that I didn't learn until after this was recorded was evaporative cooling. So if you have the hotter the matcha, the more water is going to evaporate off the surface, which can be net destructive for foam. But it turns out the higher the temperature,

typically the better extraction you get for surfactants and pectin. So you at really high temperatures are getting more cooling, which can destroy foam, but you're also getting better extraction of a lot of these, of a lot of the things that help with the foam stability. So it turns out that that destruction is about equally compensated with better extraction of things that stabilize that foam.

Interesting. So whether or not it's a 70 degrees, 80 degrees, 90 degrees, or 100 degrees, those about kind of equal out, is interesting that I didn't know. It's a fairly old research paper, I believe it was from the 90s, but that also kind of should have belonged in this because I wasn't thinking about that evaporative loss at the time playing into foam degradation. So with that, please enjoy and...

We'll keep you posted. We're about to wrap up season two of the podcast and we're excited for season three and have some pretty epic interviews either recorded or on the way and more epic updates of the machine. Yeah, with the machine. More launch details coming soon. All right. All right. Enjoy. See you.

Participant (08:29)
Specialty matcha podcast, I'm Ryan Ahn and this is my co-host Zong Jun Li. And we're the co-founders of Sanko Matcha Products.

Zongjun (Sam) Li (08:35)
Hello.

Yeah, so we launched this podcast to discuss our learning journey in Macha, share some startup stories and interview experts. So today we're going to talk about the science of whisking Macha. Ryan, since you are the main author of this article, can you give our audience a very short summary of what you're talking about?

Participant (08:58)
Sure. So the article which is on our blog is titled The Science of Matcha Whisking, and we deep dive into what exactly is matcha from a food science perspective and talk more about the mechanisms that help make it that way. And I start off the article saying that matcha is scientifically unstable, like it really shouldn't exist. It's a very weird beverage from a food science perspective because you're drinking a suspension.

So unlike coffee or other types of tea, you brew some type of solid material, there's an extraction, and then you decant it or remove the solids in some way, and then you drink the resulting liquid. And matcha is not like that at all. There is extraction going on, but because the tea is powdered so finely, those solid particles will mix into the hot water and form a suspension.

So that suspension is actually unstable. So those tiny microscopic matcha particles, which are technically imperceptible to the naked eye, and if they're milled fine enough, you shouldn't really be able to feel them with your tongue either. They range anywhere from five microns to 15 microns. And they're kind of dancing around in the water. You have these forces of Brownian motion or these random movements that happen in a liquid.

and these, you know, you have particles and molecules bumping into each other and they're kind of floating around like a bunch of smoke in a room. And because the matcha still has mass, gravity will eventually bring it and settle it to the bottom. But the finer you mill matcha and the more surface area it has, the longer it will dance. So it turns out that matcha milling has a huge impact on the stability of

a matcha suspension. Some milling methods, like ball milling or industrial milling, gives really round or spherical particle shapes, particle morphologies, and those will sink faster than those milled with the traditional Japanese millstone called an ishi-usu, which produce very jagged particles. So the article goes into that and the science behind why that creates a better suspension. And then

details. The other really interesting fact about matcha is that it contains all three states of matter. Not only do you have these solid particles floating around in water, but you also have this fantastic foam, which is really important to the sensory experience of matcha, much like, you know, micro foam is in a latte or a cappuccino. And we discuss how that foam is created, how it's made, how stable it is, and potential...

brewing improvements that you could do to make even better matcha foam.

So, Zong Jun, in your opinion, how might have the cultural significance of matcha, particularly in Japanese tea ceremony, influenced the way we approach its preparation and consumption in modern times? How do we take example from the past about whisking matcha today?

Zongjun (Sam) Li (12:03)
Wow, that's a very interesting question. I mean, today, like how we drink matcha is very different from what people drink matcha, you know, hundreds or thousands of years ago. You know, matcha has been consumed since Song dynasty in China, although in a very different format. And then it was later on evolved into a Japanese tea ceremony.

first in Kyoto and then spread across the entire Japan. And then nowadays we have all these kinds of matcha drinks in different specialty cafe shops that people consume from day to day basis. You know, like the way people ultimately consume matcha and treat matcha as...

a either element in a ceremony or a shot of caffeine before they go to office, the intention of consuming matcha has changed a lot. But that doesn't necessarily translate into the preparation method. Like nowadays you still see people like trying to whisk matcha in a matcha bowl with a bamboo made chasen.

that doesn't necessarily have any difference with tools being used 100 years ago in Japan, where matcha was meant to be consumed maybe once a day or once a week, and the tools are very carefully maintained and prepared and used and then cleaned again with this very set-up ceremonial procedure.

Whereas nowadays, same tools have been used in specialty coffee shops maybe like a hundred times a day. You see all these very sad looking chasen sitting around. And you know, it's a really weird retrofitting of a past tool into this modern consumption habit.

Participant (14:00)
Yeah, and I see a really interesting reason for this and I think it goes back to the article is that matcha preparation is difficult It will clump on you if you do things wrong If the water temperature is you know too hot or too cold you can have various problems with taste and texture You know, it's a lot of people have a lot of trouble getting very good matcha foam It's like a difficult thing. It's very technique driven thing

And even like tea ceremony practitioners can spend a lifetime getting perfect foam, perfect whisking technique. And when you see someone who's really good, it's like, wow, like I know both Sam and I have seen some really impressive matcha whiskers out there. And you're like, oh my God, that must have taken decades.

Zongjun (Sam) Li (14:36)
Yeah.

That's right, that's right. I mean like it takes a lot of practice just to get the matcha foam up When you I mean like both you and I have been professionally trained in matcha ceremony schools You know me in Omotesenke doesn't really care about matcha foam that much But you know in other schools like Urasenke Foam is very important and also like if you go back to Song dynasty like

half matcha or mocha at a time, you know, foam up is considered to be a competition. Like people actually compete against each other about how thick the foam and how long-lasting the foam is.

Participant (15:26)
Yeah, for certain.

Zongjun (Sam) Li (15:28)
you know, like you hand the bowl to a barista who has been probably signed up a week ago and try to ask him or her to, you know, prepare a perfect bowl of matcha with perfect foam. I think that's a big ask. And what you've been seeing is that like people sometimes they just give up trying like they don't really, you know, try to whisk a good bowl of matcha or produce.

Participant (15:43)
That's a big ask

Zongjun (Sam) Li (15:56)
nice thick foam, they just mix matcha with water and then pour that into a shot of milk and then voila, matcha latte is ready

Participant (16:06)
Or, you know, if they do have any interest, there's really only one place to look, and it's to look to tea ceremony. Some of the earliest missionaries, so to speak, for the spread of matcha popularity in the world were Japanese tea ceremony practitioners. Like, Urasenke in particular has done a fantastic job going from country to country, city to city where there are practitioners that have been doing it for decades and all across the world.

in many different languages these schools exist. And naturally, they are the experts. So when matcha became more and more popular in specialty coffee shops and other form factors, you look to where people who have experience are. And I think that's why we see a lot of this retrofitting. And it will be interesting to see new tools be invented that take matcha science and

functional design and merge the two to create, to help remove some of this lifetime of skill that it requires to get a perfect sensory outcome.

Zongjun (Sam) Li (17:12)
Yeah, I think it's necessary because imagine training someone to meet that outcome. The resources need to be spent from a per-person basis, probably going to be immense. It doesn't necessarily take that much resources to train a barista to produce a good espresso or a good Americano, right?

But on the other hand, if with all these current tools available, in order to produce a good cup or bowl of matcha, or even a good cup of matcha drinks, it's going to take more time and going to take a lot more resources.

Participant (17:51)
Exactly. So, Zong Jun, also in this article, we talk a lot about quality or producing a good sensory outcome or a good tasting cup of matcha. And this question around quality and the characteristics that make up a high quality bowl of matcha, to what degree do you agree with me

about the objective and subjective interpretations of quality. So I talk about in the article, you don't want it too bitter, you don't want any clumps, you want to produce stable foam. But if you go to an Omotesenke Japanese tea ceremony practitioner, they're not going to want a lot of foam. You go to Song Dynasty, Mocha, high quality matcha was a lot of foam. Or maybe there's some parallel universe where extremely bitter tea is considered

very prized and you actually want to express those flavors. So what degree is all of this arbitrary when we talk about...

Zongjun (Sam) Li (18:46)
Yeah.

Yeah, I mean like it really depends on you know what is being valued essentially right like in Chanoyu, tea is oftentimes not really the center or you know the main character under the spotlight and if you go to Song Dynasty Mocha ceremonies you know

same theory applies, you know, like it's not really about the taste of the tea, it's about all the other things that people care about. So I would say that definitely in the parallel universe, probably people are competing against each other about how bitter their tea can be. But you know, from a pure sensory or flavor point of view,

especially nowadays when people drink matcha for its flavor and sometimes for its effect. That's not really related to who whisk the thickest foam or who has the most elegant gesture in folding the napkin or have the best matching theme of calligraphy and flower to the tea and to the season.

It's about the flavor. It's about how nice and how smooth the tea is, how creamy the foam is, and how nicely the tea, the matcha, is mixed with milk or oat milk, depending on your dietary choices. But it's about the taste. People care about the taste. People don't necessarily care about how beautiful.

you prepare the matcha, or how well you have been trained and how deeply, how deep your understanding about matcha is. Regular consumers don't care about that. They care about how nice the cup of tea in their hand is.

Participant (20:42)
A lot of people will judge it just based on like their primary sensory experience. Like you can imagine someone who's never tried matcha before, right? If even at the highest end matchas that are like very umami, they probably take a sip and be like, wow, that's weird. But you're definitely judging it on the taste for sure.

Zongjun (Sam) Li (20:57)
Haha

Yeah, that's right. I mean, like, you know, the same thing happens in coffee too. Like, people spend years trying to perfect their skill of the latte art. But nowadays people drink latte mostly in paper cups with a lid on it. Like, they don't care about the latte art at all. Or they don't even have the ability to appreciate it because it's covered.

I think very much the same thing goes on goes into you know matcha as well like Consumers doesn't necessarily care about things that you know Professional matcha ceremony practitioners care

Participant (21:39)
Yeah. I mean, matcha really belongs to the world now, right? Like matcha and tea ceremony, or at least some percentage of matcha, large percentage of matcha consumption is headed in a separate direction than, you know, than it was 50 years ago, where it was very intertwined to ceremony. And I think that's a good thing, right? Like these things need to evolve and it needs to exist on its own for the future of matcha and to see, you know, a lot more innovation.

Zongjun (Sam) Li (21:58)
Yeah.

Participant (22:08)
that's not restricted by what are very hierarchical institutions, which are Japanese tea ceremony schools, where very little change occurs, and it's optimized for a ceremonial context, not necessarily for the average consumer who would really enjoy a fantastic matcha.

Zongjun (Sam) Li (22:29)
Yeah, I mean, I'm not trying to talk down on, you know, Chanoyu or Song Dynasty Mocha. I mean, like, they are great. They are a form of art that need to be appreciated. But, you know, that doesn't necessarily translate into how people drink matcha nowadays. You know, it's becoming more of a daily drink, just like, you know, coffee and loose leaf tea.

with one of her tastes and also with a great, you know, physical effect. It has good levels of caffeine which I definitely need right now from day to day.

Participant (23:06)
and L-theanine. I mean, the psychological effects of drinking matcha, you know, are not only, you know, let's say rediscovered by a lot of modern health gurus, but I mean, they've been known for centuries. You know, even when matcha first moved to Japan, right, like even in the spread of tea within China, a lot of it had to do with the way it made you feel, and that cannot be overlooked.

Zongjun (Sam) Li (23:07)
And I'm feeling, that's right.

That's right.

Participant (23:34)
So, Zong Jun, why do you think so many people believe that matcha dissolves in water? Because it's actually a suspension. And what are there some things that we can do to get people more interested in matcha science? Like we see a very rich ecosystem of this in coffee, around extraction theory and grind science, and you have all these different grinders which give you different grind size distributions, etc.

and like all the alchemy around espresso. why don't we see the equivalent in matcha and in tea more generally? It just doesn't seem the specialty tea culture, at least in the English speaking West, hasn't really spent a lot of focus on this.

Zongjun (Sam) Li (24:15)
Okay, Ryan, you are asking a lot of questions here. First about matcha being a suspension, not a solvent. I guess it's really because of how phenomenally matcha can be mixed with water. I mean, it looks like matcha is dissolved because how tiny the powder is.

I think it's just a common misunderstanding from a pure physical appearance of matcha versus you see how other loose leaf teas, tea is still tea and the water is still water although it changed the color at the end.

Participant (24:56)
Actually, you and I had a very interesting conversation a few months ago. I was asking if fresh preparing coffee was common in China and in Chinese households. Like, you know, every, you know, in the U S and Europe, everyone has like, you know, a Mr. Coffee, coffee pot or a mocha pot or something where they're perfect. They're interacting with ground coffee to brew coffee. And you said, you know, the average Chinese person, the way they brew coffee in their mind, when you.

Zongjun (Sam) Li (25:16)
Yeah.

Participant (25:23)
What comes to mind when you say how do you brew coffee is you take a scoop of this powder and you mix it with water right For like a billion people like making coffee is where you dissolve a liquid And I think it's kind of the opposite for matcha on this side of the world

Zongjun (Sam) Li (25:30)
And then...

Yep, I would certainly agree on that. I mean, it's not just China, but also a lot of places in Asia and Southeast Asia, the common habit in the household is really instant coffee. It's not like third wave coffee with all these equipment like Chemex and V60. It's still very much a new thing to a lot of Asian countries and Asian culture.

on the other side of the world.

Participant (26:04)
So how do we get a rich ecosystem of what we see in coffee? Like the brew differences between a Chemex or a V60, or the differences among all these like conical burr grinder or flat burr grinders. You see companies like Fellow, right, creating very accessible high-end grinders. Like where is all of this science-based innovation for matcha?

Zongjun (Sam) Li (26:20)
Yeah.

Yeah, I think, you know, fundamentally, I think it's really just a difference between the East and the West. You know, in Western culture, like taking a scientific approach to a matter is a very common practice, you know, trying to deconstruct a subject into theories and components that can be understand and can be replicate.

is a very important thing whereas in you know in China or Japan or a lot of countries in Asia Aesthetic and you know the philosophical kind of appreciation to a subject Is the key right? You know you see in Chinese tea ceremony it's all about you know the tea and the effect and you know like

back in the literati times, it's a component of how tea and calligraphy and water ink painting art can all be linked together in a coherent way. In South Korea, it's all about meditation with Zen Buddhism. And in Japan, it's all about Chanoyu. It's about Ichigo Ichie. It's about creating...

a moment that can only be appreciated at the time and cannot be replicated in the future. It's a totally opposite kind of approach to the same matter. So I think the very origin of these two cultures' growth is the reason why there's a fundamental difference.

Participant (28:08)
That's fascinating. Never thought about it that way. And, you know, even for Japan and Japanese culture, it's probably you see the extreme of what we see in Eastern culture.

Zongjun (Sam) Li (28:18)
Yeah, yeah, that's right. I mean, it's the furthest from the from the West.

Participant (28:23)
Ha ha ha. Fair enough.

Zongjun (Sam) Li (28:26)
So, Ryan, you know, like both in China and Japan, foaming up this beautiful powder green tea is a very important component of their ceremonies. Can you talk a little bit more about the science of how matcha gets foam up? Like, how do you essentially create this really interesting thick foam in this...

in this beverage, because you know, like in coffee, you don't necessarily foam up coffee. You have to have milk as an addition to be able to produce a beautiful cream or a beautiful foam top. But matcha seemed to be able to do it by itself.

Participant (29:03)
Yeah, for sure. Well, you do see it a little bit in espresso when you have that type of extraction. You can get a very stable microfoam but yeah, and pour over coffee would be very concerning. Some foam. But actually, it's a fascinating science. We dug into the literature a bit. So one, tea naturally has surfactants in it, and surfactants are kind of what makes, help make bubbles bubbles.

Zongjun (Sam) Li (29:08)
Oh, that's right, that's right.

Mm-hmm.

Ha ha ha!

Participant (29:26)
In chemistry, that's the term, surfactant. And what's happening, so you have those. And there was an interesting paper looking at the effect of whether or not the actual matcha particles, so it's like 5 micron, 5 to 10 micron matcha particles, whether they helped, hindered, or were part of the foam. And it turns out they're actually part of the foam. So they exist within the inner membrane. And they actually help stabilize this foam.

And in foam science, there's a concept called drainage rate. So anytime you make any type of foam, it will hold part of the liquid that's in the system. And it holds it like a sponge. And you let it do its thing and let time get involved, right? It will slowly drain and the drainage will destabilize the foam. And it turns out that there's an equation.

Zongjun (Sam) Li (30:01)
Hmm

Participant (30:17)
and it's commonly referenced by a lot of coffee people who are trying to optimize textured milk and foam That every time you cut a bubble size in half you quadruple the The retention of that liquid so the drainage rate will be have a 4x improvement. So really fine micro foam Is a very stable foam

And the beauty of a chasen and one of the reasons why it's considered one of the best performing ways to mix matcha together, versus just putting it in a blender or using one of those mechanical stirring rods, is because it's able to subdivide the bubbles so well. When you have 80 to 100 tines that are nearly parallel with each other, go back and forth, you're subdividing these bubbles into small enough pieces that they become very stable.

and reduce the drainage rate. The other thing that's really fascinating about, there's actually two more fascinating things. The next is a phenomenon called Oswald ripening. And it's a phenomenon where anytime you have any foam or froth, the tiny bubbles over time will give their air to the larger bubbles. So if you want to create a stable foam, you need to create very even bubble size. And when you combine

even size and small size you get a very stable phone which is what a well mixed bowl of matcha is.

Zongjun (Sam) Li (31:38)
Interesting.

It's like bubble playing monopoly.

Participant (31:42)
Yeah, they landed on go. And the last one that was very interesting that really came out of nowhere is I was looking up what the optimizing, what the extraction rate was for a lot of the tea surfactants that exist within tea as it relates to temperature.

Zongjun (Sam) Li (31:45)
Hahaha.

Participant (32:02)
Because you have very low temperature water, in general, you get very low extraction. If you put some random sencha or loose leaf green tea in water, it's going to extract, in room temperature water, it's going to extract very slowly. It's kind of like a cold brew. And obviously, the hotter you go, the faster you hydrate the leaf and then you can extract things from it. And it turns out that most of the surfactants that are responsible for these bubbles peak extraction

is 70 degrees Celsius, which is really interesting because most people recommend consuming matcha between 70, or preparing matcha between 70 degree and 80 degree Celsius water. But primarily for the taste, because matcha has an unusually high number of catechins, which is a type of polyphenol or antioxidant, and those tend to extract into the water at around 80 degrees.

So there's a flavor argument, but it turns out there's also a foam argument why you want to keep your brew temperature around 70 degrees Celsius.

Zongjun (Sam) Li (33:04)
Very interesting. You know, like I never learned about all the signs of matcha back when I was practicing Chanoyu in Omotesenke. This is certainly, you know, all of these learning journey has been very interesting to me.

Participant (33:19)
Yeah. It's interesting because like you have, you know, over almost a thousand years or over a thousand years of iteration. And it really actually has converged and like just putting a scientific lens on it and having going through the research, right? We can explain like why some of those, how they converged what the same conclusions, but without necessarily

Zongjun (Sam) Li (33:41)
Yeah.

Yeah, it's almost like traditional Chinese medicine. It's like empirical science. People threw out iterations trying to optimize for some goals and they landed on something that can be scientifically explained.

Participant (33:52)
Mm.

Yeah, exactly.

Well, thank you for listening to the Specialty Matcha Podcast. I think that's all we have for today. We're going to be producing a lot more content, so please subscribe, follow. You can find us wherever you find podcasts, recommend us to a friend. We have very few ratings, so if you could give us a five star review, we'd be very appreciative. And thanks for listening. Take

Zongjun (Sam) Li (34:29)
you! Bye bye!

Participant (34:28)
Bye.