Would mean a ton if you "liked" this video! Outweighs the negative nancy dislikes I get and helps promote this video I worked quite hard on. Thank you for the support!
Hey Lance! Do you have any idea why these dislikes come in? Love these videos even though I am not this deep into the coffee world (yet)! Love your work in general, thanks Burr Mann
Love this video! Really appreciate all the time and effort that went into making it easy for us to understand the scientific paper and additionally all the testing you did to add to their conclusions. Please don't let the dislikes discourage you and keep doing what you so clearly enjoy doing!
@@shaolinhabibithat would be really cool if Lance could do a highlight summary of his deep dives! I wonder if being able to get two videos out of the same content might even have a financial benefit in regards to TH-cam ads or sponsors?
I'm 47 years old, and until three years ago, I absolutely hated coffee. I literally detested it. I called it Satan's Sputum I disliked it so much. But, that was commodity instant coffee, which is all I was aware of and had experience of. I'm now watching another Lance coffee science video and utterly captivated by it........at 7am on a Sunday morning in Scotland! Such a fascinating piece Lance. Your curious and enquiring mind is inspirational. I started with an Aeropress, then graduated to a Clever Dripper, and I'm hoping to buy my first espresso machine in the next few weeks. More science please Lance 😊
I’m 29 and I hated coffee too. I used to just drink tea. Fast forward being a barista for 6 years and just got my first home espresso machine too ! Can’t wait how ! What machine did you get ? I got the Rocket Appartamento cause it was on sale and I think it’s a beautiful Machine.
Lance is the man!! I really LOVE this approach to investigating and researching claims and backing it up with SCIENCE. It's my favorite way to approach cooking (shout out to America's Test Kitchen, Ethan Chlebowski, etc.), and I LOVE seeing it in coffee!!
My theory on why dark roast shots are going slower is 2 points. 1. we put in the same weight into the basket. If we assume that dark roasted coffee is generally lighter, we put in more ground coffee in particle number and puck height into the basket. The pressure and flow through the puck correlates with puck height. So dark roast, means higher puck with the same weight of coffee as compared to light roast. You can also notice the difference in height when tamping. 2. Dark roasts could produce more fines when grinding. If dark roasts are more „hollow“. It could produce more fines when breaking it. Maybe think like cutting through many hollow spheres glued together. So there will be more crumps.
When I saw that Lance dropped a 52 minute video on something every coffee nerd already knows about, I knew we were in for a treat. What a gift of a video. Thanks, Lance.
I don’t know how many of us nerds are out here in the world but these are my absolute favorite videos! I know they must be strenuous to make but as long as you enjoy making them I’ll also be here to watch, like, and forcibly share these videos with friends and family! Also this video is definitely tribo.
Cool study. I always let my beans sit for 60 seconds after wetting (with a little lid on top). Typically, all the water is absorbed, and none left visible on the beans and barely any left in the dosing cup. I think this is key to getting the true benefit of wetting the beans. Additionally, I feel like this lessens the chance that my burrs will be affected by the water. Might be cool to augment this study by testing different resting times to more fully absorb the water into the beans.
Thanks for all the work you have put in the video I‘ve been watching coffee videos for a long time but the amount of professionalism and knowledge you show is unparalleled.
So where I live 90% humidity level most of the time, the lowest at 70%, at this point I don’t even know what this means, Lance you’re the best. Thanks for your effort on teaching us mortals.
This video was very tribo. I love these science-based deep dives into coffee. I love how the more I watch these videos, certain pieces of knowledge get repeated from past videos helping solidify my knowledge of this subject and by extension allowing me to more concisely share neat coffee info with my peers. Today in my Data Science course it was our last day of class before finals and we were handed a quiz (which really was to incentivize us to not skip so the professor wouldn't have a (near) empty classroom) where we were asked to share something interesting with the professor. I shared my pour over recipe I use for Onyx Framily. I listed the steps and added little notes about why these steps were done the way they were. TLDR: coffee cool
Video was totally tribo, what an excellent and interesting dive into this topic, I'm sure this will spawn loads more research into the subject and I'll be eagerly awaiting more videos about it!
Very interesting Lance, and I massively appreciate your intense commitment to your videos, the work you put in for something like this is extraordinary, so thanks!!! Having watched it all, I am not convinced it is about the static... I don't see what is at play that might cause a wider range of particle sizes due to static, and reduced when static charge is reduced. I'd love to have more scientific detail on that exact theory... without it, my intuition tells me that it is specifically that the coffee is wet that causes deaggregation, and not due to reduced static but due to the sticking together of wet things, surface tension... This makes the bits stick, so they get re-crushed to a finer average.... just a theory about the (it's just a) jump to the left... Thanks again fella.
I really enjoy that you put the paper in the description so we can go and read it for ourselves. I really enjoy coffee research and geology it is very interesting.
Why are YT creators so delicate? Most people are commenting jokes about Lance’s passion for coffee. It’s the reason we appreciate and watch. I don’t see any outright offensive comments
I'm pretty confident I never said anything about negative comments. My only comment was for people to like the video so the statistics are better. Very, very odd comment calling creators delicate. Not computing.
EK43 is a great grinder for this study because it's reliable and consistent. For solid methodology you need to isolate all the variables to have only one control. In this case, the control was the hydration. The choice to control for the grinder is an implicit acknowledgement that each grinder has a different mechanical action that will introduce an unwanted variable to the study.
Superbly tribo, Lance! I love the science aspect of well, everything but especially when it comes to something I've taken for granted for years...say, coffee. You made so many great points...especially about the apparent (and may I say ODD) omission of something as seemingly obvious as using a variety of grinders in such a complex paper. You're great at reading and interpreting and you do this with excellent critical thinking. I found this video to be fascinating and informative. I'm with you when it comes to the questions we don't completely understand and I'm betting every grinder engineer in the world is excited to (try to) find ultimate solutions for the interesting results of the "extra RDT" findings! Well done, my boy (I know you wanted to be a teacher...well, you ARE!).
This was probably already be answered, but it doesn't seem to apply to steeped coffees, like French press. If there's a chance it changes things, I'd also like to know what it does to V60 and Aero-Press grinds. A lot of work, but you earned my like and subscription today. Keep up the good work.
Bravo. Well done! So we need this to happen at some level without or maybe still with water in the grind chamber. Some combination of charging the burrs and/or grind chamber negative/positive? Or charge both burrs positive and another device like anti popcorn negative? Interesting side note, I frozen single dose and notice a few interesting things when doing it. I've been wanting to play around with a few variables. W/ & w/o RDT'ing before and after freezing, letting the vials rest at room temperature for condensation build up (time), capped/uncapped/out of glass vial (airflow/room temp humidity being more readily available). A time laps lapse would be neat to see the condensation build up difference. Lots of variables to line up and many might end up being satisfactory in the end. Hoarfrost on coffee might just be the hottest thing in the cold beans world, the quest for the perfect frozen single dose continues.
Coulombs are a unit of charge (amps/second), millivolts are a unit of voltage. It’s not the same thing. You cant convert from millivolts to coulombs without more information (the resistance)
I know they aren't the same thing lol. The question is can you have a positive voltage and a negative Coloumb measurement. It still seems a bit divided in comments. One so far thinks you can
The difference between a positive and a negative voltage is a matter of reference only. If you switch the probes you get the opposite voltage potential (your meter will show a negative instead of a positive, or vise versa). Particle charge is not referential, it won’t change unless you alter the material by adding or subtracting electrons
Absolutely intriguing video! As you said, it’s extremely difficult to differentiate between triboelectrification and fractoelectrification and running the grounds again through a coarser setting is not exactly replicating the conditions of what is actually going on during grinding. One thing I’d like to point out is bean fractures will also result in friction between the fractures, and friction will also result in more fractures, so it’s nearly impossible and probably unimportant to try and distinguish between these two forms of electrification. The video was so tribo dawg! 🤙🏻
On the note of voltage charge vs coulomb charge, I think a good way to think about it is looking at a hill/slope. For voltage: how we view the hill depends on where we are looking. It is a relative measure between 2 points. If I look up the hill, it looks like I have a long ways to climb up. If I look down the hill, it looks like I have a long ways to walk down. Both are based on your position relative to the hill. Going back to voltage, this reference is your black ground probe on the multi-meter. If you flip the red and black probes, the meter will still give you a reading, but it will be negative from what you read in the other configuration. For coloumb charge: we have an exact measure of the hill, and it is all relatively to a fixed spot (we will say sea level). Whenever I look at the hill, I know that hill goes from 900 feet above sea level to 1000 feet above sea level. It doesn't matter what perspective I have, it always stays the same. Relating back to charge, we know we have exactly 100 electrons worth of charge here or 100 protons worth of charge. Changing perspective doesn't change that's it's exactly X amount of charge. It's not a perfect analogy, but hopefully that helps clear up the differences between the two!
Completely insane video! I loved every single part of it. I’m new to the coffee world but I’m so intrigued, curious and excited to learn more! Lance, you make this process so enjoyable and your charisma adds so much to my excitement for coffee. Thank you for the work you put into your videos! Your passion shows and I love that so much!
Great video Lance! Very interesting and informative. I have noticed my shots being more watery recently now that it is a lot drier indoors here in the Southeast. I currently don't wet my coffee but I will definitely look into it now. I wanted to comment on your question on measuring charge as I am an electrical engineer with a decent understanding of this type of stuff. If my interpretation is correct, you are trying to measure net charge with a standard voltmeter / multimeter. My understanding is that this will not work. Voltage is essentially potential energy created by separating charge, Voltage (V) = Work (W) x Charge (Q). This is similar to the potential energy due to gravity of lifting a rock into the air. You can have a high voltages present with even neutral NET charges. In order to measure the net charge you will need to use more advanced equipment or techniques like they did in the paper. I really liked in the paper how they created a particle separator in order to bin the different types of particles. I think this could be an interesting follow up and you could likely replicate their separator with a Wimshurst generator, some wires and metal plates. To me, what really affects how much "static" is in the resulting grounds is the ratio of highly charged particles (positive or negative) to relatively neutral particles. The net charge really just shows how much charge is lost or gained to other parts of the process like the grinder. I would think you could have a result that is very clumpy with a NET neutral charge still. It is possible I am understanding the term net charge incorrectly but this is my first take.
Coulombs is the unit of charge (How positive and negative) and Voltage is the unit of potential, so it depends on what your reference is. For example, testing a small positive charge with reference to a large positive charge would show a potential drop from the reference to the test charge, or negative voltage reading. So you should check that you are comparing the grounds to something that is close to neutral
38:30 the dry shot after the 40mg/g shots was similar to the 10 mg/g ones due to the interior of thr grinder was more humid than when you started the whole experiment with all dry shots. With that much water, the humidity in the burrs or the entry probably increased. Edit: ok, you mention it later at 42:25.
Great idea to try: add a nebulizer feed just above where whole beans enter the grinding plates. Also test if grinding causes a negative air pressure above grinding plates; as a result, the continuous flow nebulixer output tube could have a air break close to grinder; it follows, when grinder is operating and negative pressure above grinder plates: as a result, atomized water vapor will be sucked into grinder across the airbrake on the nebulizer output tube; thereby, providing mist to all beans entering the immediate grinding area. Just a thought.
The charge imparted on your ground coffee is highly dependent on many things. Different ambient temperature and humidity will affect the charge, as will as moisture in the coffee beans. The type of burrs you have and the speed of the grinders motor will also affect the charge imparted on the beans. Does the grinder have an ionisation module installed? This will also affect charge. Flat vs Conical will affect charge. The units of charge are different things, but are not fully mutually exclusive as the influence each other. The values, however, are quite different as they are measuring different units of the charge. There are so many different variables that affect the charge on your coffee. Once your coffee is in your portafilter and in the group head, charge will be of very little effect as the group head should be earthed for safety, and often mandated in code unless the machine is double insulated (which would be a plastic group head), and as such the charge will be removed, the coffee will be discharged once in the group head. The charge will only affect during grinding stage, and mostly it will be in how much the grounds scatter rather than anything else with the taste of espresso in the end. Even on a double insulated machine, the water flowing through the puck will then change the charge and the quality of the water will affect the charge. The water alone could change the charge from positive to negative or vice versa. A note on ionisers - an ioniser will only do negative or positive ions, if your coffee is positively charged and the device has a positive ioniser, then it will make it even more positive and vice versa.
Good video. I’ll admit to treating it as a podcast, listening to it through some long Windows updates. I have to find a spritzer and see what it does. When I was young, “espresso” was Medaglia D’oro coffee made in a moka pot. We had one that was so old it didn’t have a pressure relief valve!
Could you do a video on coffee cups and how different forms affect how the taste is perceived? I just bought the origami flavour cup kit and started thinking why cafes dont use curated cups for certain coffees/beans to enhance the taste.
Wonderful. I'm convinced that the depth of cups matters significantly for taste given that coffee sediments and that stirring cannot fully homogenize the layers. The same coffee tastes different in my Nuova Point tulip cups (narrow and deep) versus my Ancap Napoli (which are shallow and wide). But the width of cups also affects the impact the aroma has on your taste sensors as well (wider cup: less aroma reaching sensors; narrower cup: more). @@LanceHedrick
the spirits and wine community are way ahead of coffee people is this. I think there is a lot of potential especially in the more fancy 3rd wave coffee shops that function more like nice wine bars with expensive pour over options and terroir, taste etc descriptions
Glad you gave this a critical look, I'm not that deep into the grinder topic and wouldn't have thought about the differences in grinder. Thanks for your work♥️
I think the benefits of grinding frozen beans may need to be reassessed as well. Past belief regarding frozen beans contributed better shot extraction due to brittleness, more even grind size and less fines... But what if cold beans are also reducing electrification thus mitigating clumping as well 🤔
If you can measure charge for different beans there could be an additional note on each coffee bag you purchase. For instance, the amount of water to add per g, and type of grinder preferred. This could also be true for light/dark coffees.
Loved this, Lance! Your content has evolved massively over the past year. You've really set yourself apart with these kinds of analytical videos. Keep it up!
Many parameters that are open from assumption: -Relative humidity -Grounded appliance (or not) -Burr type -Speed -Coffee process (not sure if variation in compound will affect surface adsorption)
Most are answered in the paper. RH I mention in the video. It is covered. The ek43 is grounded. Most grinders are. Burr type is covered. Speed is NOT covered. Coffee process is covered.
Very interesting paper and presentation, I'd love to read this in full. I was wondering throughout the video if deionized, mineralized or salt water would have made any difference as the only variable changed, but you summed that up nicely in the end. I'm glad others like nerding out on things they enjoy, knowledge enhances appreciation for anything in your wheelhouse. Wonderful class, Sir!
Fantastic video! If either fracture or friction between the beans generate static forces and heat is involved, maybe what water is doing is absorbing energy. Looking back and grinding frozen beans or better heat management in burrs could have an impact.
I think that the easiest way to test this is rather than using a voltage meter and electrometer is likely more appropriate as in this case we have a static charge leading to a static electric field which an electrometer directly measures. If you wanna be extra you can do all these measurements in an enclosed metal box which insulates your measurements from other electrical sources that would disturb your measurements!
Talking about your methodology for testing the other grinders, the pushback you received is correct. You read different voltage readings, but this is not charge. 17:31 Voltage is the force moving the charge around and is referenced (usually) to ground or 0v. Coulombs refer to the amount of electricity (energy) being moved by the voltage. Coulombs can be positive (protons) or negative (electrons).
I know that it's a ton of work but would love to see the effects of water in other grinders with horizontal burr mounts like DF64. What this also means is that variance in RDT will result in a variance in shot times and extractions which is something I never expected.
I wonder what the effects of time spent wet could have. When you RDT the water sits on the surface of the beans. If you dosed into cellars and gave the appropriate spritz then let it sit for 10, 20, 60, 300 minutes.
thank you! Been getting pelted by trolls with dislikes, which don't bother me mentally, but bugs me because the work I put into these, so this comment made my day. Thank you!!
@@LanceHedrick don't let them bug you, it's great to be able to watch someone who's light hearted yet knows exactly what they're talking about and on top of that the production quality is just great to watch. I don't know a huge amount about coffee yet here I am lol
Tribo AF dude! That made my brain very happy. Your videos are awesome, keep teaching! I've only just begun my espresso journey about a year ago and have gone so far down the rabbit hole I can't and don't want to climb out! Looking forward to more brain candy, may the force be with you 🤘🏻
Thank you for doing the hard work so we don’t have to. I started using the RDT to mitigate the overspray when grinding, I did not know it was helping with extraction. Win-win
great info and great video, Lance. Thank you. but I'm not sure about accuracy in this specific moment 24:40 if we talk about avarage particle size, it's worth mentioning, whether we're talking about quantities (units) of different particles, or about masses of different groups of particles (grouped by weight)
good point. it shows it in the paper and I took that for granted. I read it so much, and chatted with hendon so much, I took it as a given. that's an oversight. thanks for pointing it out!
This video was turbo! Thanks Lance, and so happy you also thought about putting an ionizer in the grind chamber. Would love to see what becomes of this study in future grind technology
The millivolts measurement would be an interesting finding, because thats measuring the difference in charge between 2 different areas. If both your probs were in the coffee, that might mean your getting a heterogeneous distribution of charge throughout your sample
Did this with my DF83, 4 sprays resulted in a bean jam in the grinder but pumping the bellows a few times cleared the blockage. The resulting espresso was dam tasty and noticeable better than my usual one blast of water.
Excellent video! And so much work! Loved the final discussion with the trippy music at the very end. One thought on consistency: Did you add water based on a scale reading as shown in the video? If so, its 0.1g accuracy can make it quite inconsistent for small water amounts. Adding 0.2g based on that scale display could effectively be anything between 0.1g and 0.3g, just because of the way digital numbers work: Adding 20.2g - 20.0g = 0.2g of water can either mean 20.15g - 20.049g = 0.101g, or 20.249g - 19.95g = 0.299g, or anything in between. (Sorry, I am a not-yet-recovered academic.)
Thanks for another awesome video, I was looking for similar studies regarding RDT for a long time. Just got out my R2 Extract and started measuring TDS with my Orbit. I will also check TDS for RDT and with the Ion Beam and if there are any similarities as I wanted to test that for a long time already. PS: Thanks to you, I cannot watch other coffee content anymore, as I always expect the same amount and level of scientific reasoning now 😅
It's also a good way to rust out the inside of your grinder which I learned the hard way with my 1zepresso K Ultra, I deep clean my grinder every 3 weeks and spot clean it once a week, yet after I started just putting one small spray of mist on my beans after I weighed them and stiring them with a wooden chopstick before grinding 3 weeks later when I disassembled my K ultra there was rust all down the axel, top and bottom bearings and inner frame, I make about 5 pourovers a day, so one small sparay on my beans 5 times a day through my grinder caused rusting after 3 weeks, littleraly ruined my 225 dollar 1zepresso K Ultra, did a great job of stopping the static on my light roasted beans for the 3 weeks until I discovered the rust 😂, I'm waiting on my new 1zepresso K ultra to be delivered tomorrow since I belive it's the best grinder under 600 dollars for light roast pourovers, just no more misting my beans, I'll deal with the static which is worse for me since I live in Phoenix which lacks any humidity in the air.
@LanceHedrick didn't know you couldn't rdt a hand grinder, I live in Phoenix, there's literally no humidity in the air, running light roasted bean's through any grinder causes tons of static, having around almost 0.5 gram of retention every grind, so I'm like I'll try to rdt before I grind, worked perfectly, no measurable retention at all, then when I went to do my 3 week disassembly and cleaning rust everywhere, didn't really expect that to happen with a small mist of water and living in such a dry environment, I have a cheap Encore ESP that I always rdt and has never rusted, it never crossed my mind that a quality grinder like the 1zepresso K Ultra would rust with with suck a small amount of moister mixed in with my beans, I wasn't blaming you, I actually came on line to see if anyone else had a similar issue when I saw your post, I've been using the rdt method for over a year with the Baratza, that's what I use the majority of the time to make espresso since my wife just wastes the shots to make her flavored lattes every morning, I have a Kinu M47 for my espresso, I purchased the 1zepresso K Ultra specifically for my light roast pourovers, never needed to rdt my Kinu since for some reason I never had a retention problem with it, most likely since I rarely make espresso for myself unless I have company I want to impress them with a great shot, not wasting my time hand grinding shots for my wife when she just makes flavored lattes, the Baratza ESP does good enough for flavored lattes.
@LanceHedrick 1zepresso has a add on Facebook and TH-cam showing someone doing RDT with their K-ultra in their pourover comercial, I responding, they replied and said we recommend making sure to make sure your grinder is in a well ventilated area when using the RDT method, I responded by saying I live in Phoenix which is one of the driest cities in the world and my grinder is in my open kitchen concept that is about 1200sqft between the kitchen and living room in a 2600sqft house so it's well ventilated 😆
Instead of a spray bottle, I used a metal chopstick, which I dip into clean water and then dip and stir into my beans before grinding. 2-3 dips is perfect for 20 grams.
Triboelectric effect. There's a chart for that with the charge of different materials. To make a Van de Graf generator usually you use a small metal comb with fine teeth, maybe one of the stationary burrs could be elecrically charged to study this effect.
yes! I was reading about that chart. so funny how ancient it seems to just compare things on a chart, but it's really cool. I'm sure there is something to be done there. I know Hendon is already working on more stuff, maybe this is part of it.
Hey Lance, thank you for this interesting video! I really need to know where I can get this lovely coffee cup you've sitting there next to you on the counter.
Lance you're killing it, triboo. Awesome video. I wonder if you're able to change the results if you slowly raise moisture level of roasted beans by putting them into a humidor for instance. Best regards
Ok, Volts and Coloumbs for coffee drinkers. Volts are potential, i.e., how high is the coffee in your cup. Coloumbs are number of charged particles, or how much liquid is in the cup. The two are related by capacitance, i.e., how wide is your cup. A higher capacitance, or a wider cup, needs more electrons, or more coffee liquid, to reach the same potential, or height of coffee in the cup. Since negative capacitance does not exist, Volts and Coloumbs will always have the same sign.
This video was tribo, Lance! Thanks for dropping some knowledge on us. Before watching this I thought RDT was just for purposes of decreasing retention.
If you get this to a simple system it would be great to have a follow-up and see exactly how it is done. For example after hydrating the roasted beans, is there a latency where you cover the beans and allow the moisture to soak in? If so how long? Or are they ready for immediate use? This could work out to a good low tech and cheap way to improve expresso yields once it is perfected.
Little spritz ( little)gummed up my Breville smart grinder Pro after about week began slipping. I had to take the whole thing apart and clean it. Maybe it is just SGP and doesn’t do it on other more expensive grinders. But I won’t spritz the beans on my new Barista Touch Impress.
Great review and followup experiments! Additional thoughts (just from this "tribo" video, I haven't read the paper yet): 1. do WDT needles *only* mechanically break up macro clumps, or do they also reduce aggregate, and since they're conductive do the help with discharge at all? 2. would making sure there's a low-resistance path between the burrs help reduce charge accumulation during grinding? (Or do most grinders end up having a good path anyway since they're mostly-metal construction for robustness)
This is really cool! I love the video. I'm really interested in how much the lipids, static charge of the given grinder, the lubrication-al effect of the water, emulsification effects of the water, fats (lipids), amino acids, minerals, and more all effect different total amounts of distribution, extraction, cooling effects of the grinding process, the dissipation of static voltage into charge fields of the polar water vs (temp) polar water thanks to the fats, amino acids, minerals (types of charge, molecular, oxidation, & more states), and all of that for the contents of the roasted seeds. Truthfully I'm fine with the water right now, it works and it works well. The ionic exchange I feel could be something if charge plates (ground and electrode like a car's spark plug) might be doable but it always introduces heat into the grinding process. Electrons moving always seems to do that lol :p I imagine grounding and z current flow (current flowing 1 direction creates and attractive electromagnetic field that heads towards the wire or electrical circuit) would allow for it to be near and create a capture of the electron movement states in the fields to a ground point that would help. The best part is that it would make it such that you could run an electricmotor right there off of that alone, then you can force the burrs to be held in place thanks to needing to have the motor in a sleeve housing that makes it so the burrs are forced to be within a given tolerance through connection points. Like gears connected to the burrs, but it would be an electricmotor outside, the burrs being attached directly to the motor, then the independently move as contact points from the sleeve housing, but also flow current and fields around the beans. Anyways, I've rambled on this comment for too long. But its a big chemical solid that has many states that change during its movement in the grinding process, having a way to have fairly small voltage and static forces (like a capacitor) dump into something nearby while allowing for a cooling effect of some kind and a easing lubricative solution with something there to help basic movement of grains into separate channels as the get rolled out to a correct size and shape will help. While hard, not impossible. Its why I look at roller styles of grinders, they can be cooled internally in the cylinders while using that as a way to help pattern the outside to further separate each grain into specific channels and even help with a given grinding style. I.e. standard looking wavy patterns on it so that way it makes it move side to side while being forced through the total size gap. I usually just go with gears though, using hydraulic fluid for movement isn't often necessary just because its typically a heat that in small moments quickly is pushed to ir, electron movement, and a field capture like its suggesting (field capture is a given stuck around static charge build up where they form temporary moments of "work" energy to keep themselves stuck together and in a roughly similar entropedic state of pressure, electromagnetic force, & vibrational (typically seen as thermal momenta stuff but it goes deeper into "tugs" of others fields and how that makes losses of fields and virtual particles and attraction forces while having electron orbits drop so that light is emitted but that creates given types of hall effects, lorentz forces, spin states, etc etc) changes) but during these moments, while heat is usually lost in the initial break fairly quickly & also most states collapse back to their given lower states entropedically, that energy is usually captured by only escaping gases, other grains, and the physical heat sink of the grinder burrs themselves. Light loves to bounce, and interact much more often with certain molecular structures and elements than others, basically minerals - fats - metals (more elemental) - etc that introduce resonance frequencies to the input light of the burrs, the electro dumps of the charge of the given air, metals, and of the given increase is using a type of high electromagnetic interference motor. All of it is to say that on these micron scales, a lot of cool nano-chemistry & quantum forces are going on to transfer more heat into the given area than is typical when allowed to channel heat to a near-by exchange area instead. Essentially, while there are no roasted seeds there, it dumps heat into the area and then allows for even transfer of the air escaping, electron flow to a ground area, and a way for light to be captured to a destructive interference area and channeled away from the grind, all while allowing for the grains to be cooled from the burrs themselves. It might make it much, much easier on the system to try a burr that just allows for something nearby that isn't there for anything other than to soak up heat and electrons. Still emulsification (maybe why the puck eroded from all the extra water but also had high extraction yields *shrugs*) of the fats into water during grinding to soak given ionic acidic bonds of the fats during movement away from pairing of other organic compounds might be helping, while still providing a cushion against the burr surface such that vibration and neutralization of charge pairing & electron movement is subbed with an insulator like material that still helps ease the surface fracturing of the roasted seeds. Up until the given increase like you said, in which case a given gaseous, fatty, and compound rich type of grain soup is created that forces a more even thermal transfer, emulsification, & then even better electrical conductivity of the compounds that allows for this charge to be reduced as that given electrostatic force, electron movement, and compound field generation has the ability for it to go there more easily it creates less electrical resistive heating & capacitor like grain formation moments. Maybe coffee lube will be something they start selling so you don't have to worry about corrosion lol. I could see it.
Take quality coffee beans, grind them very fine in a cup type grinder - I use a Mr. Coffee grinder, no longer made - and just grind the crap out of the beans. Put the grind into a manual cone type filter with unbleached cone filter - Melitta makes a cone filter/carafe that's very inexpensive - and pour in your hot water from your tea pot so that the grinds are tossed around and get fully suspended. Best. Coffee. Ever. The bitter foamy stuff floats on top and stays in the filter while the coffee goodness flows through. Also said to be healthier.
Would the friction heat be reduced if you use beans straight out of the freezer? It may be just placebo but I generally prefer using cold beans over room temp ones.
Love the video. ❤Thank you Lance for the exhaustive look at this. Quick question… will it make a difference if we spritz chilled water on the beans? following on… are the paper’s results seen on different temperature beans? Such as frozen?
Could this also be, why wdt has such a significant effect? If we have a large aggregate, of positively and negatively charged particles, then a metal needle could readjust charges and thus break up coffee better than for example a plastic stick. I always feel like I am not hitting everything but the effect on brew times is still really significant.
I tried this on my sculptor 078s with medium roasted beans at 800rpm and essentially I had to grind finer from 2.5 (dry) on the dial all the way down to 1.2 (for espresso), I have no clue what’s going on but the coffee did indeed look ALOT fluffier out of the grinder. At the same grind setting the shot was pulling ALOT faster, I got to 2:1 ratio in 10 seconds after spritzing instead of 30 seconds dry. Crazy
I can give you my opinion on your voltage / charge measurement (high voltage engineer here). What voltage meter did you use exactly? Can you draw a schematic of your electrical connections?
There where parts of the video that slipped into turbo encabulator sounding script to me but some of the finding are fascinating. It's all the little side bits of research as well. Great Video :)
Awesome video, nice to finally have some hard evidence of the benefits of RDT. Did you keep track of the humidity and temperature of the room during your testing? Would be interesting to see the impact of this on how much water is needed to RDT
@@LanceHedrick ah, I meant kept track of it during your testing as a value as you were testing overnight and the humidity might have dropped over such a long time period
This isn’t just helping the coffee community, it’s helping scientific critical thinking in general. Am I going to g to watch them all? Probs not. Did I watch this whole one? Nope (although most). But do I love that Lance is finding time, space and value in doing this? Yes!
Amazing video lance. Wanted to add a point about particle distribution and roast level: Another way to think about the difference in PD light vs dark, in addition to burr movement, is the plasticity (or brittleness) of light vs dark. A less brittle coffee would be able to deform (squish?) more under pressure from the burrs, meaning some larger particles could pass thru that did not reach the pressure threshold required to fracture them. A brittle coffee particle of the same size might rather fracture than deform, resulting in an overall smaller grind output. Same deal really, just viewed from the side of the bean rather than burr.
Yes. I've discussed this at length in previous videos. Brittleness is a major factor but I don't think can account for the 100 micron difference. I am currently getting the PSDs to see if the shift left is median or peak.
Really enjoyed this video. Just like journal club 😂 I didn’t catch if you used an Ek43 as well sort as a control. Would definitely have been interesting to see if you could have replicate some of the findings as well. I don’t think I’ll be changing my setup yet, just like you said it is not quite as controlled a variable as just using dry beans 👍🏽
Would mean a ton if you "liked" this video! Outweighs the negative nancy dislikes I get and helps promote this video I worked quite hard on. Thank you for the support!
Hey Lance! Do you have any idea why these dislikes come in?
Love these videos even though I am not this deep into the coffee world (yet)! Love your work in general, thanks Burr Mann
Do I need to spray before using a hand grinder?
Hope all the negative Nancy's become neutralized aggregates from the positive 👍s in your turbo videos! : )
Love this video! Really appreciate all the time and effort that went into making it easy for us to understand the scientific paper and additionally all the testing you did to add to their conclusions. Please don't let the dislikes discourage you and keep doing what you so clearly enjoy doing!
@@JoseVasquez-ye6zoYes, I would think so based on the two charge mechanisms that Lance introduced from the paper.
Didn’t know anybody could talk about making beans wet for and hour but here we are
I can talk about anything for an hour lol
@@LanceHedrick and we love you for it ❤️
Someone needs to make a TLDR of it this, I am interested ,but not that interested or have that much time lmao
@@shaolinhabibithat would be really cool if Lance could do a highlight summary of his deep dives! I wonder if being able to get two videos out of the same content might even have a financial benefit in regards to TH-cam ads or sponsors?
no- two videos never do well. but I do have a SKIPPERS time cue. I guess I will rename it to TLDR as it seems people aren't noticing it lol
I'm 47 years old, and until three years ago, I absolutely hated coffee. I literally detested it. I called it Satan's Sputum I disliked it so much. But, that was commodity instant coffee, which is all I was aware of and had experience of.
I'm now watching another Lance coffee science video and utterly captivated by it........at 7am on a Sunday morning in Scotland! Such a fascinating piece Lance. Your curious and enquiring mind is inspirational.
I started with an Aeropress, then graduated to a Clever Dripper, and I'm hoping to buy my first espresso machine in the next few weeks.
More science please Lance 😊
😂😂😂
I’m 29 and I hated coffee too. I used to just drink tea. Fast forward being a barista for 6 years and just got my first home espresso machine too ! Can’t wait how ! What machine did you get ?
I got the Rocket Appartamento cause it was on sale and I think it’s a beautiful Machine.
Standart ad made me laugh. Awesome video Lance. Thanks for all of the hard behind-the-scenes work that you do that goes into these videos.
thank you, tanner! stoked you took some time to check it out
Oh and the video is tribo. Just finished.
@tannercolsoncoffee stud
Thanks!
wow thank you so much!
I’m waiting for the kickstart grinder that’s going to lightly mist the beans directly onto the burrs during grinding 😂
Titus makes a volumetric doser for the EK43 which auto-RDTs the beans. It's uh, cost-prohibitive though.
Already working on it, DIY. It works better and it's easier if you put the mist just above the burrs.
Lance is the man!! I really LOVE this approach to investigating and researching claims and backing it up with SCIENCE. It's my favorite way to approach cooking (shout out to America's Test Kitchen, Ethan Chlebowski, etc.), and I LOVE seeing it in coffee!!
Thank you! And humbling parallel! Thanks for watching!
The people you mention are not following a scientific approach, they just present it that way.
My theory on why dark roast shots are going slower is 2 points.
1. we put in the same weight into the basket. If we assume that dark roasted coffee is generally lighter, we put in more ground coffee in particle number and puck height into the basket. The pressure and flow through the puck correlates with puck height. So dark roast, means higher puck with the same weight of coffee as compared to light roast. You can also notice the difference in height when tamping.
2. Dark roasts could produce more fines when grinding. If dark roasts are more „hollow“. It could produce more fines when breaking it. Maybe think like cutting through many hollow spheres glued together. So there will be more crumps.
When I saw that Lance dropped a 52 minute video on something every coffee nerd already knows about, I knew we were in for a treat. What a gift of a video. Thanks, Lance.
I don’t know how many of us nerds are out here in the world but these are my absolute favorite videos! I know they must be strenuous to make but as long as you enjoy making them I’ll also be here to watch, like, and forcibly share these videos with friends and family! Also this video is definitely tribo.
Cool study. I always let my beans sit for 60 seconds after wetting (with a little lid on top). Typically, all the water is absorbed, and none left visible on the beans and barely any left in the dosing cup. I think this is key to getting the true benefit of wetting the beans. Additionally, I feel like this lessens the chance that my burrs will be affected by the water. Might be cool to augment this study by testing different resting times to more fully absorb the water into the beans.
Thanks for all the work you have put in the video I‘ve been watching coffee videos for a long time but the amount of professionalism and knowledge you show is unparalleled.
So where I live 90% humidity level most of the time, the lowest at 70%, at this point I don’t even know what this means, Lance you’re the best. Thanks for your effort on teaching us mortals.
This video was very tribo. I love these science-based deep dives into coffee. I love how the more I watch these videos, certain pieces of knowledge get repeated from past videos helping solidify my knowledge of this subject and by extension allowing me to more concisely share neat coffee info with my peers.
Today in my Data Science course it was our last day of class before finals and we were handed a quiz (which really was to incentivize us to not skip so the professor wouldn't have a (near) empty classroom) where we were asked to share something interesting with the professor. I shared my pour over recipe I use for Onyx Framily. I listed the steps and added little notes about why these steps were done the way they were.
TLDR: coffee cool
Video was totally tribo, what an excellent and interesting dive into this topic, I'm sure this will spawn loads more research into the subject and I'll be eagerly awaiting more videos about it!
Very interesting Lance, and I massively appreciate your intense commitment to your videos, the work you put in for something like this is extraordinary, so thanks!!! Having watched it all, I am not convinced it is about the static... I don't see what is at play that might cause a wider range of particle sizes due to static, and reduced when static charge is reduced. I'd love to have more scientific detail on that exact theory... without it, my intuition tells me that it is specifically that the coffee is wet that causes deaggregation, and not due to reduced static but due to the sticking together of wet things, surface tension... This makes the bits stick, so they get re-crushed to a finer average.... just a theory about the (it's just a) jump to the left...
Thanks again fella.
Yes I thought that too. And tested it. And discuss it in the video
I really enjoy that you put the paper in the description so we can go and read it for ourselves. I really enjoy coffee research and geology it is very interesting.
Same. As a geologist and cafe owner, I find so much joy in the similarities to hydrocarbon generation and making espresso
Why are YT creators so delicate? Most people are commenting jokes about Lance’s passion for coffee. It’s the reason we appreciate and watch. I don’t see any outright offensive comments
Wait. How am I delicate?
I'm pretty confident I never said anything about negative comments. My only comment was for people to like the video so the statistics are better. Very, very odd comment calling creators delicate. Not computing.
EK43 is a great grinder for this study because it's reliable and consistent. For solid methodology you need to isolate all the variables to have only one control. In this case, the control was the hydration. The choice to control for the grinder is an implicit acknowledgement that each grinder has a different mechanical action that will introduce an unwanted variable to the study.
Superbly tribo, Lance! I love the science aspect of well, everything but especially when it comes to something I've taken for granted for years...say, coffee. You made so many great points...especially about the apparent (and may I say ODD) omission of something as seemingly obvious as using a variety of grinders in such a complex paper. You're great at reading and interpreting and you do this with excellent critical thinking. I found this video to be fascinating and informative. I'm with you when it comes to the questions we don't completely understand and I'm betting every grinder engineer in the world is excited to (try to) find ultimate solutions for the interesting results of the "extra RDT" findings! Well done, my boy (I know you wanted to be a teacher...well, you ARE!).
This was probably already be answered, but it doesn't seem to apply to steeped coffees, like French press. If there's a chance it changes things, I'd also like to know what it does to V60 and Aero-Press grinds. A lot of work, but you earned my like and subscription today. Keep up the good work.
Bravo. Well done! So we need this to happen at some level without or maybe still with water in the grind chamber. Some combination of charging the burrs and/or grind chamber negative/positive? Or charge both burrs positive and another device like anti popcorn negative?
Interesting side note, I frozen single dose and notice a few interesting things when doing it. I've been wanting to play around with a few variables. W/ & w/o RDT'ing before and after freezing, letting the vials rest at room temperature for condensation build up (time), capped/uncapped/out of glass vial (airflow/room temp humidity being more readily available). A time laps lapse would be neat to see the condensation build up difference. Lots of variables to line up and many might end up being satisfactory in the end. Hoarfrost on coffee might just be the hottest thing in the cold beans world, the quest for the perfect frozen single dose continues.
Coulombs are a unit of charge (amps/second), millivolts are a unit of voltage. It’s not the same thing. You cant convert from millivolts to coulombs without more information (the resistance)
I know they aren't the same thing lol. The question is can you have a positive voltage and a negative Coloumb measurement. It still seems a bit divided in comments. One so far thinks you can
The difference between a positive and a negative voltage is a matter of reference only. If you switch the probes you get the opposite voltage potential (your meter will show a negative instead of a positive, or vise versa). Particle charge is not referential, it won’t change unless you alter the material by adding or subtracting electrons
Absolutely intriguing video! As you said, it’s extremely difficult to differentiate between triboelectrification and fractoelectrification and running the grounds again through a coarser setting is not exactly replicating the conditions of what is actually going on during grinding. One thing I’d like to point out is bean fractures will also result in friction between the fractures, and friction will also result in more fractures, so it’s nearly impossible and probably unimportant to try and distinguish between these two forms of electrification.
The video was so tribo dawg! 🤙🏻
On the note of voltage charge vs coulomb charge, I think a good way to think about it is looking at a hill/slope.
For voltage: how we view the hill depends on where we are looking. It is a relative measure between 2 points. If I look up the hill, it looks like I have a long ways to climb up. If I look down the hill, it looks like I have a long ways to walk down. Both are based on your position relative to the hill. Going back to voltage, this reference is your black ground probe on the multi-meter. If you flip the red and black probes, the meter will still give you a reading, but it will be negative from what you read in the other configuration.
For coloumb charge: we have an exact measure of the hill, and it is all relatively to a fixed spot (we will say sea level). Whenever I look at the hill, I know that hill goes from 900 feet above sea level to 1000 feet above sea level. It doesn't matter what perspective I have, it always stays the same. Relating back to charge, we know we have exactly 100 electrons worth of charge here or 100 protons worth of charge. Changing perspective doesn't change that's it's exactly X amount of charge.
It's not a perfect analogy, but hopefully that helps clear up the differences between the two!
Completely insane video! I loved every single part of it. I’m new to the coffee world but I’m so intrigued, curious and excited to learn more! Lance, you make this process so enjoyable and your charisma adds so much to my excitement for coffee. Thank you for the work you put into your videos! Your passion shows and I love that so much!
Thanks so much for the kind words!
Great video Lance! Very interesting and informative. I have noticed my shots being more watery recently now that it is a lot drier indoors here in the Southeast. I currently don't wet my coffee but I will definitely look into it now.
I wanted to comment on your question on measuring charge as I am an electrical engineer with a decent understanding of this type of stuff. If my interpretation is correct, you are trying to measure net charge with a standard voltmeter / multimeter. My understanding is that this will not work. Voltage is essentially potential energy created by separating charge, Voltage (V) = Work (W) x Charge (Q). This is similar to the potential energy due to gravity of lifting a rock into the air. You can have a high voltages present with even neutral NET charges. In order to measure the net charge you will need to use more advanced equipment or techniques like they did in the paper.
I really liked in the paper how they created a particle separator in order to bin the different types of particles. I think this could be an interesting follow up and you could likely replicate their separator with a Wimshurst generator, some wires and metal plates. To me, what really affects how much "static" is in the resulting grounds is the ratio of highly charged particles (positive or negative) to relatively neutral particles. The net charge really just shows how much charge is lost or gained to other parts of the process like the grinder. I would think you could have a result that is very clumpy with a NET neutral charge still. It is possible I am understanding the term net charge incorrectly but this is my first take.
thank you for this! I knew someone would pull through hahaha.
Nice review
Coulombs is the unit of charge (How positive and negative) and Voltage is the unit of potential, so it depends on what your reference is. For example, testing a small positive charge with reference to a large positive charge would show a potential drop from the reference to the test charge, or negative voltage reading. So you should check that you are comparing the grounds to something that is close to neutral
38:30 the dry shot after the 40mg/g shots was similar to the 10 mg/g ones due to the interior of thr grinder was more humid than when you started the whole experiment with all dry shots. With that much water, the humidity in the burrs or the entry probably increased.
Edit: ok, you mention it later at 42:25.
Nice! The wife and I watched a baby Lance video the other day...Ethipoia Worka brewing. Awesome
CNN just published an article on this study, referencing this video and quoting Lance. Good job getting the word out.
Probably the best video you’ve ever done. Riveting from start to finish!
thank you! Multiple weeks in the making. appreciate you!
Great idea to try: add a nebulizer feed just above where whole beans enter the grinding plates. Also test if grinding causes a negative air pressure above grinding plates; as a result, the continuous flow nebulixer output tube could have a air break close to grinder; it follows, when grinder is operating and negative pressure above grinder plates: as a result, atomized water vapor will be sucked into grinder across the airbrake on the nebulizer output tube; thereby, providing mist to all beans entering the immediate grinding area. Just a thought.
The charge imparted on your ground coffee is highly dependent on many things. Different ambient temperature and humidity will affect the charge, as will as moisture in the coffee beans. The type of burrs you have and the speed of the grinders motor will also affect the charge imparted on the beans. Does the grinder have an ionisation module installed? This will also affect charge. Flat vs Conical will affect charge.
The units of charge are different things, but are not fully mutually exclusive as the influence each other. The values, however, are quite different as they are measuring different units of the charge.
There are so many different variables that affect the charge on your coffee. Once your coffee is in your portafilter and in the group head, charge will be of very little effect as the group head should be earthed for safety, and often mandated in code unless the machine is double insulated (which would be a plastic group head), and as such the charge will be removed, the coffee will be discharged once in the group head. The charge will only affect during grinding stage, and mostly it will be in how much the grounds scatter rather than anything else with the taste of espresso in the end. Even on a double insulated machine, the water flowing through the puck will then change the charge and the quality of the water will affect the charge. The water alone could change the charge from positive to negative or vice versa.
A note on ionisers - an ioniser will only do negative or positive ions, if your coffee is positively charged and the device has a positive ioniser, then it will make it even more positive and vice versa.
Great info.
I’ve been following your channel for a while now, and you get better with every video dude.
Thanks for the amazing work.
Good video. I’ll admit to treating it as a podcast, listening to it through some long Windows updates. I have to find a spritzer and see what it does.
When I was young, “espresso” was Medaglia D’oro coffee made in a moka pot. We had one that was so old it didn’t have a pressure relief valve!
Could you do a video on coffee cups and how different forms affect how the taste is perceived? I just bought the origami flavour cup kit and started thinking why cafes dont use curated cups for certain coffees/beans to enhance the taste.
Yes. Working on it
Wonderful. I'm convinced that the depth of cups matters significantly for taste given that coffee sediments and that stirring cannot fully homogenize the layers. The same coffee tastes different in my Nuova Point tulip cups (narrow and deep) versus my Ancap Napoli (which are shallow and wide). But the width of cups also affects the impact the aroma has on your taste sensors as well (wider cup: less aroma reaching sensors; narrower cup: more). @@LanceHedrick
the spirits and wine community are way ahead of coffee people is this. I think there is a lot of potential especially in the more fancy 3rd wave coffee shops that function more like nice wine bars with expensive pour over options and terroir, taste etc descriptions
Glad you gave this a critical look, I'm not that deep into the grinder topic and wouldn't have thought about the differences in grinder.
Thanks for your work♥️
I think the benefits of grinding frozen beans may need to be reassessed as well. Past belief regarding frozen beans contributed better shot extraction due to brittleness, more even grind size and less fines... But what if cold beans are also reducing electrification thus mitigating clumping as well 🤔
If you can measure charge for different beans there could be an additional note on each coffee bag you purchase. For instance, the amount of water to add per g, and type of grinder preferred.
This could also be true for light/dark coffees.
Loved this, Lance! Your content has evolved massively over the past year. You've really set yourself apart with these kinds of analytical videos. Keep it up!
Thank you! Appreciate it sincerely!
Many parameters that are open from assumption:
-Relative humidity
-Grounded appliance (or not)
-Burr type
-Speed
-Coffee process (not sure if variation in compound will affect surface adsorption)
Most are answered in the paper. RH I mention in the video. It is covered. The ek43 is grounded. Most grinders are. Burr type is covered. Speed is NOT covered. Coffee process is covered.
What a tribo video. More detail than I expected.
Awesome work Lance!! As always
looking good and energized :) best shameless plu i've ever seen with magazine btw hehe
Very interesting paper and presentation, I'd love to read this in full. I was wondering throughout the video if deionized, mineralized or salt water would have made any difference as the only variable changed, but you summed that up nicely in the end. I'm glad others like nerding out on things they enjoy, knowledge enhances appreciation for anything in your wheelhouse. Wonderful class, Sir!
Fantastic video! If either fracture or friction between the beans generate static forces and heat is involved, maybe what water is doing is absorbing energy. Looking back and grinding frozen beans or better heat management in burrs could have an impact.
I think that the easiest way to test this is rather than using a voltage meter and electrometer is likely more appropriate as in this case we have a static charge leading to a static electric field which an electrometer directly measures. If you wanna be extra you can do all these measurements in an enclosed metal box which insulates your measurements from other electrical sources that would disturb your measurements!
Talking about your methodology for testing the other grinders, the pushback you received is correct. You read different voltage readings, but this is not charge. 17:31 Voltage is the force moving the charge around and is referenced (usually) to ground or 0v. Coulombs refer to the amount of electricity (energy) being moved by the voltage. Coulombs can be positive (protons) or negative (electrons).
I know that it's a ton of work but would love to see the effects of water in other grinders with horizontal burr mounts like DF64.
What this also means is that variance in RDT will result in a variance in shot times and extractions which is something I never expected.
I wonder what the effects of time spent wet could have. When you RDT the water sits on the surface of the beans. If you dosed into cellars and gave the appropriate spritz then let it sit for 10, 20, 60, 300 minutes.
I swear you could talk abiut the most boring of subjects and id still watch. Youre just an awesome guy to watch!
thank you! Been getting pelted by trolls with dislikes, which don't bother me mentally, but bugs me because the work I put into these, so this comment made my day. Thank you!!
@@LanceHedrick don't let them bug you, it's great to be able to watch someone who's light hearted yet knows exactly what they're talking about and on top of that the production quality is just great to watch. I don't know a huge amount about coffee yet here I am lol
thank you! that is great to read. hope you enjoy the rants lol!
Tribo AF dude! That made my brain very happy. Your videos are awesome, keep teaching! I've only just begun my espresso journey about a year ago and have gone so far down the rabbit hole I can't and don't want to climb out! Looking forward to more brain candy, may the force be with you 🤘🏻
Thank you for doing the hard work so we don’t have to. I started using the RDT to mitigate the overspray when grinding, I did not know it was helping with extraction. Win-win
I like how you always go into very fine detail .
thank you! Takes a lot of work, but it's the stuff i'd want to see online, so I figure I would put it there haha. appreciate your support!
46:31 - “Dead in the water”. Lance, you’re killing me! 😅
great info and great video, Lance. Thank you.
but I'm not sure about accuracy in this specific moment
24:40 if we talk about avarage particle size, it's worth mentioning, whether we're talking about quantities (units) of different particles, or about masses of different groups of particles (grouped by weight)
good point. it shows it in the paper and I took that for granted. I read it so much, and chatted with hendon so much, I took it as a given. that's an oversight. thanks for pointing it out!
This video was turbo! Thanks Lance, and so happy you also thought about putting an ionizer in the grind chamber. Would love to see what becomes of this study in future grind technology
I have a coffe grinder with a conical mills in hardened and tempered steel .Water in everyday not the best idea maybe?Great video thanks Lance.
yes. don't do it lol!
Commenting for the algorithm. Thank you for doing this video, Lance! Good job :-)
The millivolts measurement would be an interesting finding, because thats measuring the difference in charge between 2 different areas. If both your probs were in the coffee, that might mean your getting a heterogeneous distribution of charge throughout your sample
It's not measuring the difference in charge though, it measures the difference in electrical potential
@@iansweetland6292 Agreed. The electrical potential is a product of the relative differences in charge
52 minutes video? oh boi i am up for a ride! prepping popcorn - LETS GO
Hope you enjoy!
Did this with my DF83, 4 sprays resulted in a bean jam in the grinder but pumping the bellows a few times cleared the blockage. The resulting espresso was dam tasty and noticeable better than my usual one blast of water.
Where did you get that ceramic cup from?! It’s beautiful
Excellent video! And so much work! Loved the final discussion with the trippy music at the very end. One thought on consistency: Did you add water based on a scale reading as shown in the video? If so, its 0.1g accuracy can make it quite inconsistent for small water amounts. Adding 0.2g based on that scale display could effectively be anything between 0.1g and 0.3g, just because of the way digital numbers work: Adding 20.2g - 20.0g = 0.2g of water can either mean 20.15g - 20.049g = 0.101g, or 20.249g - 19.95g = 0.299g, or anything in between. (Sorry, I am a not-yet-recovered academic.)
Thanks for another awesome video, I was looking for similar studies regarding RDT for a long time. Just got out my R2 Extract and started measuring TDS with my Orbit.
I will also check TDS for RDT and with the Ion Beam and if there are any similarities as I wanted to test that for a long time already.
PS: Thanks to you, I cannot watch other coffee content anymore, as I always expect the same amount and level of scientific reasoning now 😅
It's also a good way to rust out the inside of your grinder which I learned the hard way with my 1zepresso K Ultra, I deep clean my grinder every 3 weeks and spot clean it once a week, yet after I started just putting one small spray of mist on my beans after I weighed them and stiring them with a wooden chopstick before grinding 3 weeks later when I disassembled my K ultra there was rust all down the axel, top and bottom bearings and inner frame, I make about 5 pourovers a day, so one small sparay on my beans 5 times a day through my grinder caused rusting after 3 weeks, littleraly ruined my 225 dollar 1zepresso K Ultra, did a great job of stopping the static on my light roasted beans for the 3 weeks until I discovered the rust 😂, I'm waiting on my new 1zepresso K ultra to be delivered tomorrow since I belive it's the best grinder under 600 dollars for light roast pourovers, just no more misting my beans, I'll deal with the static which is worse for me since I live in Phoenix which lacks any humidity in the air.
Why did you rdt a hand grinder lol
@LanceHedrick didn't know you couldn't rdt a hand grinder, I live in Phoenix, there's literally no humidity in the air, running light roasted bean's through any grinder causes tons of static, having around almost 0.5 gram of retention every grind, so I'm like I'll try to rdt before I grind, worked perfectly, no measurable retention at all, then when I went to do my 3 week disassembly and cleaning rust everywhere, didn't really expect that to happen with a small mist of water and living in such a dry environment, I have a cheap Encore ESP that I always rdt and has never rusted, it never crossed my mind that a quality grinder like the 1zepresso K Ultra would rust with with suck a small amount of moister mixed in with my beans, I wasn't blaming you, I actually came on line to see if anyone else had a similar issue when I saw your post, I've been using the rdt method for over a year with the Baratza, that's what I use the majority of the time to make espresso since my wife just wastes the shots to make her flavored lattes every morning, I have a Kinu M47 for my espresso, I purchased the 1zepresso K Ultra specifically for my light roast pourovers, never needed to rdt my Kinu since for some reason I never had a retention problem with it, most likely since I rarely make espresso for myself unless I have company I want to impress them with a great shot, not wasting my time hand grinding shots for my wife when she just makes flavored lattes, the Baratza ESP does good enough for flavored lattes.
@LanceHedrick 1zepresso has a add on Facebook and TH-cam showing someone doing RDT with their K-ultra in their pourover comercial, I responding, they replied and said we recommend making sure to make sure your grinder is in a well ventilated area when using the RDT method, I responded by saying I live in Phoenix which is one of the driest cities in the world and my grinder is in my open kitchen concept that is about 1200sqft between the kitchen and living room in a 2600sqft house so it's well ventilated 😆
Instead of a spray bottle, I used a metal chopstick, which I dip into clean water and then dip and stir into my beans before grinding. 2-3 dips is perfect for 20 grams.
Triboelectric effect. There's a chart for that with the charge of different materials. To make a Van de Graf generator usually you use a small metal comb with fine teeth, maybe one of the stationary burrs could be elecrically charged to study this effect.
yes! I was reading about that chart. so funny how ancient it seems to just compare things on a chart, but it's really cool. I'm sure there is something to be done there. I know Hendon is already working on more stuff, maybe this is part of it.
Hey Lance, thank you for this interesting video! I really need to know where I can get this lovely coffee cup you've sitting there next to you on the counter.
Lance you're killing it, triboo. Awesome video. I wonder if you're able to change the results if you slowly raise moisture level of roasted beans by putting them into a humidor for instance. Best regards
Full nerd mode on. I love it!! Great video thanks for explaining really great!
Ok, Volts and Coloumbs for coffee drinkers. Volts are potential, i.e., how high is the coffee in your cup. Coloumbs are number of charged particles, or how much liquid is in the cup. The two are related by capacitance, i.e., how wide is your cup. A higher capacitance, or a wider cup, needs more electrons, or more coffee liquid, to reach the same potential, or height of coffee in the cup.
Since negative capacitance does not exist, Volts and Coloumbs will always have the same sign.
This video was tribo, Lance! Thanks for dropping some knowledge on us. Before watching this I thought RDT was just for purposes of decreasing retention.
That was an outstanding ad transition at the beginning there
If you get this to a simple system it would be great to have a follow-up and see exactly how it is done. For example after hydrating the roasted beans, is there a latency where you cover the beans and allow the moisture to soak in? If so how long? Or are they ready for immediate use? This could work out to a good low tech and cheap way to improve expresso yields once it is perfected.
Little spritz ( little)gummed up my Breville smart grinder Pro after about week began slipping. I had to take the whole thing apart and clean it. Maybe it is just SGP and doesn’t do it on other more expensive grinders. But I won’t spritz the beans on my new Barista Touch Impress.
Great video again 👏
Looking forward for that zerno longterm review. And lastly, Where can I get those cups?
you know, that I know, that Lance is the best!
I need espresso, you got my head spinning man! ;) Love it!!
Barata grinders use carbon steel burrs. They rust if wet! Is that a show stopper?
Great review and followup experiments! Additional thoughts (just from this "tribo" video, I haven't read the paper yet):
1. do WDT needles *only* mechanically break up macro clumps, or do they also reduce aggregate, and since they're conductive do the help with discharge at all?
2. would making sure there's a low-resistance path between the burrs help reduce charge accumulation during grinding? (Or do most grinders end up having a good path anyway since they're mostly-metal construction for robustness)
Hey Lance thanks for the great content. As always very informative and very unique!
There are assorted "anti-static" tools used by audiophiles to de-static lps. I wonder if you could zap your grounds prior to tamping?
This is really cool! I love the video. I'm really interested in how much the lipids, static charge of the given grinder, the lubrication-al effect of the water, emulsification effects of the water, fats (lipids), amino acids, minerals, and more all effect different total amounts of distribution, extraction, cooling effects of the grinding process, the dissipation of static voltage into charge fields of the polar water vs (temp) polar water thanks to the fats, amino acids, minerals (types of charge, molecular, oxidation, & more states), and all of that for the contents of the roasted seeds. Truthfully I'm fine with the water right now, it works and it works well. The ionic exchange I feel could be something if charge plates (ground and electrode like a car's spark plug) might be doable but it always introduces heat into the grinding process. Electrons moving always seems to do that lol :p I imagine grounding and z current flow (current flowing 1 direction creates and attractive electromagnetic field that heads towards the wire or electrical circuit) would allow for it to be near and create a capture of the electron movement states in the fields to a ground point that would help.
The best part is that it would make it such that you could run an electricmotor right there off of that alone, then you can force the burrs to be held in place thanks to needing to have the motor in a sleeve housing that makes it so the burrs are forced to be within a given tolerance through connection points. Like gears connected to the burrs, but it would be an electricmotor outside, the burrs being attached directly to the motor, then the independently move as contact points from the sleeve housing, but also flow current and fields around the beans.
Anyways, I've rambled on this comment for too long. But its a big chemical solid that has many states that change during its movement in the grinding process, having a way to have fairly small voltage and static forces (like a capacitor) dump into something nearby while allowing for a cooling effect of some kind and a easing lubricative solution with something there to help basic movement of grains into separate channels as the get rolled out to a correct size and shape will help. While hard, not impossible. Its why I look at roller styles of grinders, they can be cooled internally in the cylinders while using that as a way to help pattern the outside to further separate each grain into specific channels and even help with a given grinding style. I.e. standard looking wavy patterns on it so that way it makes it move side to side while being forced through the total size gap.
I usually just go with gears though, using hydraulic fluid for movement isn't often necessary just because its typically a heat that in small moments quickly is pushed to ir, electron movement, and a field capture like its suggesting (field capture is a given stuck around static charge build up where they form temporary moments of "work" energy to keep themselves stuck together and in a roughly similar entropedic state of pressure, electromagnetic force, & vibrational (typically seen as thermal momenta stuff but it goes deeper into "tugs" of others fields and how that makes losses of fields and virtual particles and attraction forces while having electron orbits drop so that light is emitted but that creates given types of hall effects, lorentz forces, spin states, etc etc) changes) but during these moments, while heat is usually lost in the initial break fairly quickly & also most states collapse back to their given lower states entropedically, that energy is usually captured by only escaping gases, other grains, and the physical heat sink of the grinder burrs themselves. Light loves to bounce, and interact much more often with certain molecular structures and elements than others, basically minerals - fats - metals (more elemental) - etc that introduce resonance frequencies to the input light of the burrs, the electro dumps of the charge of the given air, metals, and of the given increase is using a type of high electromagnetic interference motor. All of it is to say that on these micron scales, a lot of cool nano-chemistry & quantum forces are going on to transfer more heat into the given area than is typical when allowed to channel heat to a near-by exchange area instead. Essentially, while there are no roasted seeds there, it dumps heat into the area and then allows for even transfer of the air escaping, electron flow to a ground area, and a way for light to be captured to a destructive interference area and channeled away from the grind, all while allowing for the grains to be cooled from the burrs themselves.
It might make it much, much easier on the system to try a burr that just allows for something nearby that isn't there for anything other than to soak up heat and electrons. Still emulsification (maybe why the puck eroded from all the extra water but also had high extraction yields *shrugs*) of the fats into water during grinding to soak given ionic acidic bonds of the fats during movement away from pairing of other organic compounds might be helping, while still providing a cushion against the burr surface such that vibration and neutralization of charge pairing & electron movement is subbed with an insulator like material that still helps ease the surface fracturing of the roasted seeds. Up until the given increase like you said, in which case a given gaseous, fatty, and compound rich type of grain soup is created that forces a more even thermal transfer, emulsification, & then even better electrical conductivity of the compounds that allows for this charge to be reduced as that given electrostatic force, electron movement, and compound field generation has the ability for it to go there more easily it creates less electrical resistive heating & capacitor like grain formation moments.
Maybe coffee lube will be something they start selling so you don't have to worry about corrosion lol. I could see it.
Take quality coffee beans, grind them very fine in a cup type grinder - I use a Mr. Coffee grinder, no longer made - and just grind the crap out of the beans. Put the grind into a manual cone type filter with unbleached cone filter - Melitta makes a cone filter/carafe that's very inexpensive - and pour in your hot water from your tea pot so that the grinds are tossed around and get fully suspended.
Best. Coffee. Ever. The bitter foamy stuff floats on top and stays in the filter while the coffee goodness flows through. Also said to be healthier.
Would the friction heat be reduced if you use beans straight out of the freezer? It may be just placebo but I generally prefer using cold beans over room temp ones.
Love the video. ❤Thank you Lance for the exhaustive look at this.
Quick question… will it make a difference if we spritz chilled water on the beans?
following on… are the paper’s results seen on different temperature beans? Such as frozen?
Almost an hour of Lance talking bout a niche espresso topic that will very marginally improve your cup?
Yes, sir!
Could this also be, why wdt has such a significant effect? If we have a large aggregate, of positively and negatively charged particles, then a metal needle could readjust charges and thus break up coffee better than for example a plastic stick. I always feel like I am not hitting everything but the effect on brew times is still really significant.
I tried this on my sculptor 078s with medium roasted beans at 800rpm and essentially I had to grind finer from 2.5 (dry) on the dial all the way down to 1.2 (for espresso), I have no clue what’s going on but the coffee did indeed look ALOT fluffier out of the grinder. At the same grind setting the shot was pulling ALOT faster, I got to 2:1 ratio in 10 seconds after spritzing instead of 30 seconds dry. Crazy
Im too old to know what tribo is, but I'm sure I love it... like I loved this video :)
I can give you my opinion on your voltage / charge measurement (high voltage engineer here). What voltage meter did you use exactly? Can you draw a schematic of your electrical connections?
There where parts of the video that slipped into turbo encabulator sounding script to me but some of the finding are fascinating. It's all the little side bits of research as well. Great Video :)
Made a coffee just before watching as I knew I'd have to stay alert to absorb it all. Wasn't disappointed. 👍
Awesome video, nice to finally have some hard evidence of the benefits of RDT.
Did you keep track of the humidity and temperature of the room during your testing? Would be interesting to see the impact of this on how much water is needed to RDT
yep! I mention this in the video. check out time cues!
@@LanceHedrick ah, I meant kept track of it during your testing as a value as you were testing overnight and the humidity might have dropped over such a long time period
it was constantly between 42-48%.
This isn’t just helping the coffee community, it’s helping scientific critical thinking in general. Am I going to g to watch them all? Probs not. Did I watch this whole one? Nope (although most). But do I love that Lance is finding time, space and value in doing this? Yes!
Amazing video lance. Wanted to add a point about particle distribution and roast level:
Another way to think about the difference in PD light vs dark, in addition to burr movement, is the plasticity (or brittleness) of light vs dark. A less brittle coffee would be able to deform (squish?) more under pressure from the burrs, meaning some larger particles could pass thru that did not reach the pressure threshold required to fracture them. A brittle coffee particle of the same size might rather fracture than deform, resulting in an overall smaller grind output.
Same deal really, just viewed from the side of the bean rather than burr.
Yes. I've discussed this at length in previous videos. Brittleness is a major factor but I don't think can account for the 100 micron difference. I am currently getting the PSDs to see if the shift left is median or peak.
@@LanceHedrick as a science nerd, I really appreciate your diligence and depth of thought on this topic. Thank you!
Heck yeah! Thank you!
Really enjoyed this video. Just like journal club 😂 I didn’t catch if you used an Ek43 as well sort as a control. Would definitely have been interesting to see if you could have replicate some of the findings as well. I don’t think I’ll be changing my setup yet, just like you said it is not quite as controlled a variable as just using dry beans 👍🏽
in your opinion would implimenting the rdt and the slow feeding suggested by this paper make cheaper grinders more viable for espressos?