The Beginners Guide to Coffee Extraction and TDS (Total Dissolved Solids)

Move over long discussions of extraction and TDS.
Learn what extraction is and how to make respected coffee every time.

Coffee extraction and TDS are not as complicated as you think.

What is extraction? This is a phrase and a word that gets batted around a lot. People will talk about the extraction level, whether it’s too high or too low.

So what exactly is coffee extraction?

Basically, you take clean water, you take a kettle, pour it through coffee grounds, and you end up with a brewed cup of coffee. Literally, that is all extraction is. So what it boils down to when it comes to brewing coffee is how you extract how much you extract.

Those types of questions are actually what people are referring to when they talk about extraction levels. So to understand extraction, you have to kind of take a trip back in history.

Coffee Chemistry and the Science Behind Coffee That Tastes Great!

In 1952 professor Earl Lockhart with the coffee brewing Institute conducted some research and he was trying to find the optimal taste preference for coffee. What he found out is that if anywhere from 18 to 22% of the coffee bean was dissolved into the beverage, then for the most part people like that. Now coffee has the potential to have about 28, upwards of 30% of the coffee matter dissolved into the water.

So what brew methods do what barista do when you brew coffee at home, what you're doing is actually taming that you're controlling how much of the potential coffee matter ends up in the bathroom in the beverage.

That's all the differences between coffee brew methods, metal filters, paper filters, all these things.

All you're doing is controlling that 18 to 22% range that is ending up in the cup.

Now if I were to just talk about that aspect of it without mentioning TDS, then I'd be doing you an injustice.

So TDS, it is a scientific measurement that stands for total dissolved solids. So what TDS measure is the actual components, the coffee matter, the coffee stuff that is in this cup right here, sort of the range that we're going for. Like that TDS percentage that we're going for is about 1.35% in general.

That's about where coffee tastes good.

There's a margin of error with that, though. So what 1.35% denotes is that 1.35% of the stuff in this coffee is actual coffee matter. It is coffee solids, it's things like cell walls and coffee particles, things like that. The other 98.65% is going to be water. So when somebody talks about a total dissolve solid or a TDS or a TDS percentage, all they're referring to is how much of coffee matter is actually in the cup itself.

Now TDS, it's more or less a derivative of that 18 to 22% so kind of on a chart. The two work together.

So you're controlling the amount of coffee matter that's ending up in the beverage and then you're controlling the dilution or the concentration of the coffee in the actual cup.

Honestly, that's all extraction is. There's some kind of like fancy ways to go about measuring it and explaining it and so forth. But when somebody talks about an extraction being too high, typically what they're saying is that their concentration in the cup is greater than 1.35% when they're saying my extraction level was low, sort of what that denotes is that the concentration level is below 1.35% for concentrations that are higher, where you start getting more of say like on that 22 to 23% coffee matter dissolved in the beverage kind of spectrum.

When you get in that range, you're going to get really kind of like muddied and bitter and chalky sort of flavors in the cup. If you're below that TDS, like say in the 1.1 to 1.15% TDS, that means about, you know, 16 or 17% of the coffee ended up in the actual cup, and then the flavor on that, it's going to be a washed out. It's going to be diluted, it's going to be a little bit sour and just kind of boring in general.

Hopefully some of that made sense. If you guys have questions, definitely reach out to us and I'd be happy to answer what I can on that and clarify what I can. Catch you in the next one!

[tonnyanglagahit]

Thank you so much 😊 it really helps me understand this,

[arunkumarprasad]

Thanks for the wonderful explanation of TDS. Can you also explain Extraction Yield%? I can't figure out how it can be 18-22%! Thanks in advance.

[godblessthelessfortunate]

I need help with math. I have a TDS meter that measures in PPM. If I get a reading of 1987 ppm in a brewed cup (pour over with 1:16 grounds to brewed coffee ratio), is it as easy is dividing by 1 million to get percent? I used 15g coffee grounds and got 240g brewed coffee. I get 0.1987% which is no where near the ball park. I use remineralized RO water with a TDS of 20 ppm.

[angelsheart]

Ok thank you flr this, but can you help out explaining how to calculate that tds and know what the appropriate number is? You know how to calculate it manualy and know that the number i get is approximately close to the number i get through refractometer and that it is a good number? That is what I dont get. Please?

[ggivensjr]

Man, in your effort to simplify you made it less understandable. So bottom line how do I a non scientist relate tds to concentration (ebf%)? What is calculation for determining tds of 1.35% = 18-22% concentration? Can I get an affordable tds meter? Is there a specific tds meter for coffee? Does the meter need calibration to distinguish between coffee and other particulates? Is there a meter to calculate concentration?

[jorchi]

79 views only you need more promotion bro

[hakeemnaa]

be simple
dont talk about people

just give the instructions
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