I'm looking forward to hearing how wrong I am about my views on the matter

 

Refractometer provides data - doesn't tell you what coffee tastes like. That said, it's a wonderful but expensive tool that saves a lot of time fine tuning the process of making coffee - especially pour over.

Just refracted a Chemex of El Salvador Finca La Ilusion. This is a powerful coffee with huge mouthfeel even at 19.5-20% extraction yield. Because of that, on taste alone, would be tempted to grind coarser to tone down the mouthfeel in the mistaken belief it's over-extracted which, thanks to the data from the refractometer, I know it isn't.

 

I always refer to it as being a post-mortem diagnostic tool, certainly helps with making informed decisions - I'd not want to do without it. Given that the variety of beans I use taste good from 19% to 23% on various methods the actual numbers are really only useful as a way of measuring brews against each other on the same bean.

 

I think I need to start saving.

 

Refractometer provides data - doesn't tell you what coffee tastes like. That said, it's a wonderful but expensive tool that saves a lot of time fine tuning the process of making coffee - especially pour over.

Just refracted a Chemex of El Salvador Finca La Ilusion. This is a powerful coffee with huge mouthfeel even at 19.5-20% extraction yield. Because of that, on taste alone, would be tempted to grind coarser to tone down the mouthfeel in the mistaken belief it's over-extracted which, thanks to the data from the refractometer, I know it isn't.

So did (or would) you change anything or did you decide that it tasted over extracted but wasn't so you left it?

 

For pour over - 19.5-20% is the best balance between body and flavour pofile. So that's what I aim for. With most beans it's pretty clear taste-wise. The Finca Ilusion is a hugely powerful coffee - having the data from the refractometer saves wasting beans.

 

Im a huge fan of low(er) TDS high(er) EY brews.

Brazens at Tilt we aim for 21.5-22% EY . An occasional 23%er surprises us with tastiness .

 

I go with a "why not both" approach, and tend to sit between 21-22% at 1.5tds, sometimes 1.6tds and 23% ey with spiffing Kenyans because why not.

i did some tests with various non coffee folk and they preferred the "stronger" brews and I got with the program

 

1.3 tds ftw

 

I think I need to start saving.

You can borrow mine for a bit if you want.

 

So preempt next weeks article and explain to me what the relationship is between TDS and EY again?

You can borrow mine for a bit if you want.

May take you up on that kind offer.

 

http://coffeestrides.blogspot.co.uk/2014/06/why-do-we-measure-everything-extraction.html?m=1

 

1.3TDS is about the higher end of our preference . Water being 155PPM and pretty ideal

Its all about the water though. An emergency aeropress with Brum tap water (58PPM) revealed 1.45TDS and it was thin and lifeless

 

TDS is is the concentration of the coffee beverage. E.g. a 10%TDS espresso is 10% dissolved coffee, 90% water, so a 40g shot would have 4g of dissolved coffee in it. A 1.5%TDS brewed coffee is 1.5% dissolved coffee, so 200g of brewed coffee at 1.5%TDS would have 3g of dissolved coffee in it.

Think of it like ABV with alcoholic drinks. But like alcoholic drinks, strength is very open to preference. It doesn't tell you much on it's own...unless at extremes, like a 1.5% espresso shot would be unlikely, unless a coffee shot (just like you wouldn't expect a bottle of whisky to be the same ABV as a typical beer).

TDS is mainly used to back calculate EY. EY is the % of the dry dose of coffee that makes it into the cup, whether brewed or espresso, there is rather more commonality here than with respect to strength (both can be good at a factor of x10 in terms of strength), but both may be preferred at the same EY, or in a similar range of EYs. However, there isn't any one right EY, it depends on grind quality & brew method, but a lot of folk find a preference for coffee 2-3% either side of 20% (so 20% of your dose is dissolved into the cup) but not always spanning the whole range of 6% (maybe +/- 1 to 1.5% for a certain preference range?).

Knowing what you have makes it easier to determine how hard you have to push to hit a preference point (usually through grind adjustments), or whether you can hit another point more easily.

 

So for example if you pulled a shot then diluted it, regardless of how much you diluted it the EY would be the same? Because there only ever was so much extracted from the bean in the first place? But the TDS would drop the more you diluted it because there would be more water and less coffee in the cup?

 

So for example if you pulled a shot then diluted it, regardless of how much you diluted it the EY would be the same? Because there only ever was so much extracted from the bean in the first place? But the TDS would drop the more you diluted it because there would be more water and less coffee in the cup?

Yeah, that's right - if you made a brew that 1.6 TDS (ie a bit strong for most preferences) but the EY was in the ballpark you could dilute it to bring the strength down. Weak over/strong under etc was hard to grasp at first. Lots of info here too: http://coffeeforums.co.uk/showthread.php?24895-Questions-on-EY-TDS-etc&p=319323

 

Yes that's a good read that thread!

 

I do add water to some of my 1.5-1.6 brews thats for sure - I just can't be faffed adjusting my recipes when I encounter a brew that's too much for that

 

Cat amoungst pigeons time.

1-1.2 tds is where we end up on the regular, and its tastes great

 

Cat amoungst pigeons time.

1-1.2 tds is where we end up on the regular, and its tastes great

That's our happy place too ; )

 

So says Matt Perger:

About a 5 minute read, very accessible. I look forward to increasing my knowledge with the articles that follow.

http://www.baristahustle.com/vstwtf-part-1/

Interesting, St Ali, they were my local in South Melbourne.

Some of their large batch pour over stuff is stunning, very very very yummy.

 

I don't see the TDS thing as being controversial - my preference changes week to week and I adjust my recipes to cater for this; that's one of the reasons I learned how to make coffee in the first place after all.

I know that the common person often complains that the 1.2-1.3 stuff is weak - expecting coffee and being given a brew more akin to tea, pumping up the TDS and keeping EY high is an antidote to that and I noticed Prufrock doing it last time I was down there (they served all three filters that I had above 1.4 TDS, the La Cabra Crazy Fruit Kenyan was at 1.5 too and was completely mind boggling) - it certainly changed my attitude to 1.3+ TDS coffee.

My parents definitely prefer the 1.4+ TDS brews (and have a preference for the lower acidity higher chocolate brews), some of the folk that visited Cafe Ashton in Lithuania couldn't get enough of that crazy Kenyan at 1.6 TDS (and I couldn't deal with it above 1.4 - bypass all the way). Pleasures of not running a shop is being able to cater for all tastes easily.

Refrac has at least made it super easy to understand the recipes needed to create stronger brews whilst keeping EY at target levels per bean, yay the refrac.

 

Interestingly I'm sat at Brew Lab right now and the filter they just served me is at 1.46 TDS, it tastes more like a 1.3, presumably this is down to the water.

 

I don't see the TDS thing as being controversial - my preference changes week to week and I adjust my recipes to cater for this; that's one of the reasons I learned how to make coffee in the first place after all.

I know that the common person often complains that the 1.2-1.3 stuff is weak - expecting coffee and being given a brew more akin to tea, pumping up the TDS and keeping EY high is an antidote to that and I noticed Prufrock doing it last time I was down there (they served all three filters that I had above 1.4 TDS, the La Cabra Crazy Fruit Kenyan was at 1.5 too and was completely mind boggling) - it certainly changed my attitude to 1.3+ TDS coffee.

My parents definitely prefer the 1.4+ TDS brews (and have a preference for the lower acidity higher chocolate brews), some of the folk that visited Cafe Ashton in Lithuania couldn't get enough of that crazy Kenyan at 1.6 TDS (and I couldn't deal with it above 1.4 - bypass all the way). Pleasures of not running a shop is being able to cater for all tastes easily.

Refrac has at least made it super easy to understand the recipes needed to create stronger brews whilst keeping EY at target levels per bean, yay the refrac.

Assuming you're brewing at 60g/L via your Lido3, that's quite a different experience for me. I generally find (with the odd exception) EY's over 20.5% don't taste good - they start getting drying and what I would describe as over-extracted. Perhaps the different water plays a big part here, I believe Chris Hendon has some further research on this to be published at some point (some water tasting better at lower EY)

 

What you extract is as important as how much you extract* - if I want a lido3 brew to taste good above 20.5/21% it needs to come through in less than 2m30s - any longer than that and gets weird fast. It is actually the odd exception that goes to 23% (literally the occasional kenyan) - most brews are 20.5-21% with a TDS of 1.4 with a your standard 60g/l v60 brew.

*Seems obvious, but with constant focus on EY it's often overlooked