Category: Brewing coffee
Get hold of the water
The water you use for brewing coffee has much influence on the taste. But to understand the whole chemistry behind is complex. Much is going on.
Here is my advise to get hold of what water to use …
Get hold of the water
The best way to get hold of the water is to do comparisons. Make cuppings with the same coffee and different water.
Read more about Water for brewing coffee.
Espresso shot by taste
When I learned espresso, the golden parameters was brew ratio 1:2 in 22-30 seconds. So, if you got 18 grams of coffee grind going in, you should go for 36 grams of brewed coffee in the cup.
This fits dark roasted coffee well. But with a light roast the espresso shot is very acidic and dry.
There have been several work-arounds to make it better. Strech the roast profile. Brew with longer preinfusion and at a lower pressure.
Here is my work-around …
Search your coffee by tasting drops during the espresso shot
Let an espresso shot run really long while you taste with a spoon to follow what taste is extracted along the way. Provided that you got a suited grind size and don’t have channeling – the development in the taste is:
Very sour and sharp at first
Then sweet and nice aroma
Then bitter
Then thin
With a dark roast this is released fairly quickly: with around double the amount water than coffee – the 1:2 brewratio.
But light roasts are denser and got less solubles than dark roasts. So the taste is released slower. This is why longer preinfusion makes sense. But also running a longer shot, like 1:3.
When I brew a light roast espresso, I always explore the coffee on hand by tasting while the shot is running.
Using 17 grams coffee in the portafilter, I skip the first 15-20 grams because they are always very acidic.
Then I taste. Only a drop at the time (or it will get too hot).
At a good grind size the good taste will start around 30 grams in the cup – and keep on until 50 to 70 grams. When the taste starts to fade or get bitter, I stop the shot.
If the shot was stopped at brewratio 1:2 (here: 34 grams) it would have been very acidic. Most of the sweetness and big aromas would have stayed back in the portafilter.
The best way to know how what brew ratio suits a given coffee, is to taste during the shot.
See my video https://www.youtube.com/watch?v=VCovMAG2LXM
Read more about the differences in light and dark roasted coffee.
Open fire dark roast
I find it fun the many ways coffee roasting is done. Here Dave Rumbler from Australia roasting coffee on open fire.
He says: “I roast fresh every morning around 1-2 kg for my coffee/tatoo shop”.
He roast so differently from how I do it.
He roast untill 2nd crack is over ! That is extremely dark (I think it is called Spanish roast) – and close to fire in the beans.
He also have a much longer roast; he gets second crack after 33 minutes – when roasting 1,5 kilo.
My roast are often within 10 minutes and around the end of first crack.
He wrote in a coffee roasting forum and asked: “It’s just started to get cold here (winter is comming up in Australia) and my roast have gone from smooth creamy to a bit bitter. And had one roast go like a sour flavour.”
That made us talk about the lenght of the roast. Maybe it got too long. One hack is to roast smaller batches.
He tried with 1 kilo and found it tasted better.
It is normal that the weather affects the roast – and that you need to adjust the way you roast.
Ethiopean style
This reminds of the traditional way of roasting coffee in Ethiopia. They roast on open fire, very dark and right before brewing.
I tried it at an ethiopean restaurant. I expected it to be very bitter, since it was roasted way into Second Crack. But is wasn’t. From later experience it seems that the bitterness developpes during storage – as does the rancid taste from the coffee oils (after 10-14 days). Read more under Light versus Dark.
I did this video at the ethiopean restaurant here in Copenhagen, Denmark
https://www.youtube.com/watch?v=ShlInpNtaBk
12 Geisha coffees
Geisha is a botanical variety of the arabica coffee and is priced markedly higher than other great specialty coffees. Geisha has a big reputation for it’s great taste. A few years ago it was still very rare. So few people had tasted them.
🎧 Also listen to my 4 podcast episodes about Geisha coffee: #9 Geisha part 1 , #10 Geisha part 2, #11 Geisha part 3 and #12 Geisha, part 4.
The reputation started with the coffee farm Esmeralda in Panama. They have been doing auctions since 2008. Almost every year the top lot achieves a higher price.
Of course, other coffee farmers saw these high prices and wanted to plant them as well. In the recent years a lot of Geishas from different countries have hit the marked.
That made me wonder:
How different are they ? Normally there is more to the taste of a coffee than the botanical variety.
And … how good are they ? How much is just hype ?
I had tasted the famous Esmeralda farm Geisha some years ago at The Coffee Collective here in Copenhagen, Denmark – and I did find it extraordinaire; very complex and dense in the taste. Impressive. But as prices was rising I was wondering about how overpriced they were.
How to do a comparison ?
When roasteries sell Geisha coffee it is often markedly more expensive than other coffee. Of course, since the green bean price is higher. Normally from a green bean company you can get samples. But rarely on the Geishas. If you want to participate in the Esmeralda farm auction you can buy samples for $ 300 ! Or that I heard some years ago.
My way of doing this is to ask around in the Danish coffee community if people want to join forces (money) and buy Geishas together for a cupping event.
They were game. Quickly we were 17. And some on the waiting list.
We bought coffees for more than € 400 !! The most expensive coffee tasting I have ever done.
Francesco Impallomeni invited us to do the cupping at Nordhavn Coffee Roasters, here in Copenhagen. Thanks for hosting ♥
Picking Geishas for the cupping event
We limited ourselves to 12 different coffees. Too many coffees can be overwhelming. A pity that good coffees drown in a crowd.
We selected them to try different countries, different processing (washed/natural/honey) and different roasteries. John Lindgreen and Andreas did the research and picked the coffees.
I got hold of one Geisha in green beans, 1 kilo. This we wanted to explore in different roasts.
We got 4 different Panama Geisha. At first no one had Geisha from the famous Esmeralda farm for sale. But when The Coffee Collective heard about our event they donated us 15 grams of Esmeralda. Just enough for one cupping cup.
Coffee farmers in Costa Rica had been quick to plant Geisha coffee. So much Geisha comes from there. We got hold of 5 Geishas from Costa Rica; different processing (red and white honey, washed and semi washed) and different farms.
Then we had 4 other countries with one coffee from each: Colombia, Bolivia, Honduras and Ethiopia.
Regarding the Ethiopian: it wasn’t a Geisha like the others. We expect all the other coffees to be the same botanical variety – gotten from Panama. But the Geisha variety grown in Panama for the past 100 years was imported from the Gesha area in Ethiopia. The same area where the Gesha Village coffee farm is situated today. Their coffee trees are from the local area. So the two kinds probably have similarities but may also have differences in the DNA.
The last round was one bean from Costa Rica; Santa Teresa, white honey. But in four different roasts. I had gotten hold of 1 kilo of green beans and had roasted 200 grams at a time.
I had heard that Geisha is only special in a very light roast. If you roast it darker it will be more ordinary. I had no idea exactly how far that was. But started by giving it 1 minute from first crack (=Development time =DT). I found it got dark very quickly. I tasted it 5 days later and found it a bit lighter. So I ventured shorter with the next roast: 45 seconds DT. Again tasted 4-5 days later. It could bear shorter. So the next batch I did 35 seconds. It seemed thinner. So I wouldn’t go shorter.
On the other hand, I wanted to explore “how to ruin a Geisha”. How little longer would it need to get boring ? My guess was 1:30 minutes DT.
The water
Here in Denmark we have great water from the tap. Very clean. It is just very hard = high in Calcium Carbonate (you can see the formation of lime scale in your kettle). That mutes many tastes in coffee. Especially in light roasted coffee.
So if you are enthusiastic about coffee you use filtered or spring water for coffee brewing. But that can be done in many ways.
So a few days before the cupping event; we tested 4 kinds of filtered water. We tested it on the Bolivia Geisha from The Coffee Collective. One of the waters was the one used for the espresso machine. That was the worst of the 4 waters. It made the coffee taste boring. The aroma of the coffee came out in the 3 other cups, but here it was muted.
With the two best waters one had a higher Calcium content – and that gave a little dryness to the coffee. The other had higher Magnesium and made the coffee taste the best.
This water had these specifications (in CaCO3 equivalents):
Magnesium 53 ppm
Calcium 55 ppm
HCO3- 54 ppm
So the ratio the KH to GH ratio was 1:2.
KH = Carbonate hardness
GH = General hardness (Magnesium plus Calcium)
The bottled water we started out with (Denice) had 117 ppm HCO3- But we lowered it by adding 7,2 mg citric acid per liter.
Such small amounts are difficult to do precise on a scale. So Andreas made a concentrated citric acid solution – and used a syringe to get the right amount for each 2 liter bottle:
Note: We didn’t test all kinds of water. Just the ones that would be operational for us to use in this cupping.
Grinding and dosage
When we tasted the water, we used a grinder in the roastery. But Andreas could remember that the Bolivia Geisha coffee tasted better with an EK43 grinder. Sweeter. Clearer aromas. So we brought a EK43.
Grind size: a bit finer than for drip coffee.
Dosage: 60 gram pr liter
We had 3 cups of each coffee because we were 17 people. We made 3 cupping spots with 5-6 people at each.
How did they taste?
First of all: you should always be careful not to judge a coffee from a single tasting. Different coffees are the best at different brewing techniques.
Here we opened the coffees on the day of the cupping. But some times a coffees get better a couple of days after opening – must be that a little oxygen does something good for taste at first.
But still it is useful to compare coffees like this – because differences stand out more clearly than when comparing out of memory.
The downside to having an all Geisha cupping is that the similarities won’t stand out. When I earlier have tasted Geishas, it has been the only one on a cupping table with other kinds of coffee. And each time the Geisha has stood out as something special: the taste was very “filled out”/ rich. And they had much sweetness.
We tasted the coffees four at the time to avoid overload. To have enough time to focus on each coffee as they cooled down. That gave 4 rounds:
Round 1 “4 countries”
We started with this round because we expected here would be the biggest difference.
No 1: Bolivia – Takesi – washed.
Roasted by The Coffee Collective, Denmark
No 2: Colombia – Finca Rosenda – Washed.
Roasted by Ditta Artigianale, Italy
No 3: Honduras – Caballero – Washed.
Roasted by Tim Wendelboe.
No 4: Ethiopia – Gesha Village – Natural.
Roasted by Gardelli, Italy
The Bolivian and Ethiopian stood out.
The Bolivian had a very deep smell. Tasted very fruity (raspberry and abricot), soft, sweet and tea like. When it cooled a nice acidity came out and it had a hint of Ethiopian bergamotte.
The Honduras reminded me of a washed Ethiopian coffee. A roaster, Kenneth, described it as bergamotte but a bit herbal – and it was missing floral notes.
Gitte had it as her favourite in this round – she described it as chocolate and vanilla . Andreas said hazelnuts and honey melon.
The Colombia was weaker in the aroma than the others – and had bitterness. I would tend to think it was roasted too dark. When it was warm I found some caramel in the taste. Right after I found they also wrote that on the bag. It also said Tangerine. I found that as it had cooled down.
On week later a few of us tried it again in cupping. This time it was much better. I liked it.
The Ethiopean Gesha Village: Andreas and Francesco had it as their favorite of the whole cupping. It had a strong natural taste. To me it dominated it all and I didn’t find it interesting. It really divided people; they either really liked it or really didn’t. Very typical for naturals.
By the way; when the coffee had cooled all the way to room temperature the natural taste was more discreet/less pronounced – and I liked it better. Andreas liked it very much and as it cooled down he found: violets, honey and blackcurrant. Kenneth said; lime fruit.
Those who didn’t like it called it over-fermented or like olives.
By the way – the Ethiopian and Bolivian coffees had the highest cost per kilo of all the coffees.
Round 2 “Panama”
No 9: Panama – Ruiz family – Natural.
Roasted by Horsham Coffee Roaster, UK
No 10: Panama – Finca Hartmann – Washed.
Roasted by Ditta Artigianale, Italy
No 11. Panama – Finca Hartmann – Natural.
Roasted by Ditta Artigianale, Italy
No 12: Panama – Esmaralda – Natural.
Roasted by The Coffee Collective, Denmark
Even though 3 of these coffees were natural they didn’t have the strong natural aroma as the Ethiopian in round 1.
They were all very good. We agreed that this was the best round.
No 10 and 11 was from the same farm, Finca Hartmann – just different processing: washed and natural. We found the washed to have “classic Geisha taste”.
Kenneth noted no 10 as jasmin, green grapes, melon, coconut, nice sweetness and acidity. Funny enough he found the jasmin only when it was warm – where as the natural processed no 11 from the same farm, he first got the jasmin when it had cooled. No 11 he also found had plum and raisin. At a little strawberry jam at first – for him a typical sign of natural process.
John had the natural (no 11) as his favorite of the whole cupping. Gitte had no 10 as her second favorit of the whole cupping.
No 9 from the Ruiz family: here some said it was roasty. As it cooled down it became my favorite of the whole cupping. It had some very seductive aromas. Kenneth got some unpleasant bitterness when it was warm. But as it cooled it disappeared and he found it amazing – with warm spices (like cloves).
We cupped it a week later in both 60 and 50 grams per liter. It was the best in 50 g/l. This time the flavor was more funky and had a tast of heavy rum.
The Esmeralda: More than 10 people liked it the best. Roaster Ida Kofod from largest specialty roastery here in Denmark, Kontra Coffee said it was among her ALL TIME favorites coffees: “This coffee has everything! Totally balanced, sweet, acidic, bitter, heavy, thin, juicy, fruity, I could go on. A very complex and clean cup, I love it.”
Kenneth was also blown away: It stood out from the rest. So clear apple acidity. Great sweetness. So complex. So many fascinating aftertastes. Light years ahead of other good coffees. Perfectly roasted coffee. He felt overly stimulated here.
The funny thing was … when I first tasted it, I thought something was wrong. A defect bean or something. Because to me it had a bad taste, like vinegar/acetic acid. Andreas got the same. This just underlines how different we taste. Two of us have a receptor for some compound that the other 15 people didn’t have. But I had earlier tasted Esmeralda coffees were I was very impressed, so it might just be this particular coffee I had a problem with.
We concluded that Geishas grown in Panama are something special. And we think that the high auction prices at the Esmeralda farm are not pure hype.
Kenneth remarked that the Peterson family put a lot of work into making the coffee at the Esmeralda farm. So if you want to make great coffee there is no short cut in just planting a Geisha coffee.
After the cupping I talked to The Coffee Collective. They told me that this Esmeralda lot was the wildest tasting coffee they ever had. They had the same experience as us: Some did not like it – but most of them loved it and was in heaven. So they asked the Peterson family if they could reproduce that coffee; make the same taste next year. They said no. There had been some weird wheather conditions during the processing. They found the taste so different so the lot wasn’t a part of the auction.
By the way – The Coffee Collective also found vinegar in the taste (as Andreas and I).
Round 3 “Costa Rica”
No 5: Costa Rica – Doña Daisy Finca Don Pepe – Red Honey.
Roasted by Has Bean, UK
No 6: Costa Rica – Finca El Potrero – white honey.
Roasted by Has Bean, UK
No 7: Costa Rica – La Candelilla – washed.
Roasted by Gardelli, Italy
No 8: Costa Rica – Montebrisas – Semi Washed.
Roasted by Ditta Artigianale, Italy
We were a bit disappointed in this round. They were not as good as the Panamanian coffees. But that was also was also difficult to follow.
The first two from Has Bean we found too dark (but not as dark as Has Bean normally roasts, some remarked). Could have been interesting to see if they would have had more aroma at lower dosage. Maybe 50 grams per liter instead of the 60 we did here.
We tried that a week later. It was better in 50 g/l. More flavors came out. But to me it was still a bit too dark roasted.
Everybody found something was wrong with the La Candelilla coffee. It was hay like/grassy. One asked if it was an older crop. No, it was from 2017. The bag didn’t have a valve. So, the CO2 release made the bag a balloon (close to exploding).
I tried it several times in the following week hoping to crack the code for brewing it. But it was difficult.
Gitte had no 8 Montebrisas as her favorite in the whole cupping. When I tasted it again a week later I could agree with her. It had both the depht and a light aromas underlining the pleasant acidity.
Kenneth felt he didn’t give these Costa Ricas time enough. He was so blown away after the Panama round. His favorit in this round was no 8 Montebrisas. In general Costa Rica coffees are more delicate, he thinks: you have to work more on roast and the brewing.
By the way – the two Has Bean coffees had the lowest cost per kilo of all the coffees.
Round 4 “Different roasts of the same bean”
12. Costa Rica – Santa Teresa – DT 35 seconds
14. Costa Rica – Santa Teresa – DT 45 seconds
15. Costa Rica – Santa Teresa – DT 1 minute
16. Costa Rica – Santa Teresa – DT 1:30 minutes
People agreed all four roasts tasted very different . And that the aroma was different from the panamanian Geishas. It had notes of roasted hazelnuts and butter. It was very sweet but maybe too much.
People had different favorites among the first three. Almost equally distributed on the 35 secs, 45 secs and 1 minuts roasts.
Everybody agreed that the 1:30 minuts was too dark. Bitter, burnt and hardly any of the aroma. But again, the question was: would it be better at lower dosage ? We didn’t get around to that. But we did make an espresso with it. And it turned out good. Almost perfume like aroma.
Two persons at the cupping prefer some bitterness in their coffee. But even for them the DT 1:30 minuts was too much. They liked the 1 minute roast the best.
Some of the participants had high bitter sensitivity. Or rather; can taste types of bitterness most of us can’t. They found the DT 1 minute bitter. And they liked the 35 seconds the best. They found it had the highest sweetness. I too liked the 35 seconds the best.
To me who had roasted them and tasted along the way to plan the next roast … this coffee is the sweetest I have ever had. And it had a very distinct roasted hazelnut aroma (like in the Nez du Café aroma kit). I don’t think I have met such a powerful hazelnut aroma before.
Conclusions
Just because you buy crazy expensive Geisha beans doesn’t mean you get great coffee automatically. You must work for it.
Do Geishas planted in other places than Panama have the same taste ?
No. Other factors like climate and soil does influence the taste. They are not all floral. But they seem all to have much sweetness.
Processing of course also influence. But the naturals from Panama were among the best naturals we have tasted.
Is the pricing of Geishas hyped ?
We think so. You can get other great tasting coffees not quite as expensive. But the famous Esmeralda farm in Panama do a good job, so we don’t think their high auctions prices are pure hype. There is a reason they are still high despite the increasing supply of Geishas from other farms. In Kenneths opinion they are light years ahead in making good coffees.
But even though there is an element of hype in the market for Geisha, I don’t think the hype is that bad. It is a driving force for the marked of high quality coffees. The hype makes buyers pay more for coffee. And the high prices makes it worth while for the coffee farmers to strive to produce superb coffee.
What I have heard from others
A Danish guy visited a Geisha farm in Panama last year. He said they roasted Geisha only 20 seconds from First Crack.
A Danish coffee farmer in Mexico told me that Geisha grown lower than 1,500 meters is not interesting.
Norwegian roaster Tony Jacobsen writes about his experience with Geishas:
“We have had Geisha private reserve from Hacienda La Esmeralda and i have tried Geisha from Geisha Village, something from Ninety Plus, i have tried the geishas from Panama Varietals. And they are all unique in their way. Now we are actually importing a Peru Geisha, getting it by plane, hopefully next week. I remember Hacienda Esmeralda from 2007 Kaffa, it was a game changer. I love geishas, they are hard to roast as you mention. But if you get them right, they are the most amazing coffees from South America. Overpriced yes, but i guess it has its market. I like them clean, not naturals because of the botanically qualities as the sweetness – that i want to come from the bean and not the processing. But the floral notes are like catching butterflies in my mindset.”
Exploring Geisha coffees with The Coffee Collective
After this cupping I visited The Coffee Collective with my recorder and interviewed Samuli Marilla about the differences in Geisha coffees. The Coffee Collective have been roasting Geisha since 2009.
We had Geisha coffees from Guatamala, Costa Rica, Bolivia and Panama in green beans.
🎧 You can listen to this in my podcast:
Looking at the green bean Geishas. They are more long and slim than avarage beans.
The bean pile on the right is the Esmaralda.
Samuli and the auction box from the Esmaralda farm with Geisha samples.
Roasting Geisha at The Coffee Collective roastery in Copenhagen.
Light versus dark roast
Tasting light roast for the first time is strange for many coffee drinkers because something is missing compared to the darker roasts.
But many coffee people loves it, because it has some great flavours that dark roasts don’t have. A good light roast have a nice sweetness and acidity – and no bitterness. But it is not easy to make it good.
Original Coffee (OC) is a coffee bar here in Copenhagen. They always have two kinds of roast for the espressomachine: a darker roast they present as “Traditional” and a lighter roast they present as “Modern”.
It’s a very good way to communicate the taste to a regular coffeee drinker. The Traditional is in the expected taste area. The Modern is different.
But light and dark roasted coffee are not only different in taste but also to work with. So if you treat a light roast like a dark it won’t taste good. And the other way around.
If you are curious to try there is a few things to know. Because they are different to work with. Below is a list with the differences. We also talk about this in Episode 8 in the podcast Coffee Roasting Navigated.
There is no common definition of when exactly a roast is light or dark. In the U.S.A. it is common to call it a light roast when stopped before the Second Crack, but still having completed First Crack. Here in Northern Europe that would be considered a medium roast. We call it a light roast when it’s stopped before the First Crack is over – or just around the end.
List of differences
Comparing dark coffee roasted to 2nd Crack versus light roasted stopped before First Crack is over or just around the end.
1. Roasting
Not all beans taste good in a light roast. High grown beans is a good place to start if you want to explore roasting light.
Not any light color roast taste good. You have to explore to find what roast profile suits the given bean.
Read more about roasting light at Kenyans for a light roast, Roast profiles and listen to the roasting podcast.
2. Dosage
This is mainly for filter/drip and french press. Regarding espresso go to #7.
When you brew a light roast: updose = use more coffee.
Light roast has less solubles than dark roast. So you need more grams of coffee.
Exactly how high dose depends on the roast and what you prefer in the taste – so go explore.
When I brew a light roast filter/drip or french press – I mostly use a dosage around 60 grams pr liter – but goes from 55 up to 70 grams pr liter depending on the coffee. It’s different where they are the best. I even know people who do 85 grams pr liter.
Darker roasts are better at lower dosage. I have even heard of people using dark espresso roast as low as 35 g/liter.
3. Grinding
Grind light roasts finer than for dark roasts. I don’t know if it’s because light roasts are less porous or again this less-solubles. But you get more of the good taste by grinding finer.
Because of the denser bean structure, I use a longer bloom phase when making drip coffee (V60, Kalita): like 45 seconds instead of the typical 30 seconds.
4. Brew water
If your tap water is hard = has a lot of chalk … then it can make a light roast brew taste boring – compared with filtered water. This is a whole science in itself and quite complicated. I have started writting about it under Water.
Best advice: try out different types of water. Different filters. Different bottled water. Explore the taste.
5. In the cup
When you taste it – pay attention to how the taste change as the coffee cools in the cup. Very light coffee do not have much taste around 70ºC but get interesting around 50ºC.
6. Milk and sugar
Be cautious with the milk. Some light roasts taste great on it’s own … but if you poor milk into it: the interesting taste will all be gone. Because the flavors are so delicate.
The same with sugar. Lighter roasts can be sweeter in itself than darker roast. So taste before you ad anything.
7. Espresso
Brewing espresso of a light roast is different than with darker roasts. There are different approaches. But a few things people agree on:
Use a large basket in the portafilter, size 18 or 21 grams for 58 mm. Light roast doesn’t seem to work well in smaller pucks.
Use longer preinfusion.
Traditional in espresso you have a rule of thumb saying: reach 1:2 brew ratio in 25 seconds. So if you have 18 gram coffee → then get 36 grams in the cup. That doesn’t seem to work with light roasts: it’s sharp, sour and do not get the aroma of the given coffee.
Again bear in mind; light roast are denser and got less solubles than dark roasts. So the good taste is not as quickly released as with dark roast.
I know of two strategies to brew light roast:
– Grind finer and pull slow long shots, like 40 seconds instead of the traditional 25 seconds. Or even 1 minute shots on a Slayer espressomachine.
– Grind so it runs faster. And go for brew ratio 1:3 (thats what I do)
To explore this try letting a shot run really long while you taste with a spoon to follow what taste is extracted. At first it is always very sour and sharp. So maybe skip the first 10 seconds that comes out. But then keep tasting along untill it gets weak (=no more taste is extracted). In this way you can tell when the good taste is extracted. In a dark roast it gets weak quicker than with the light roasts. Read more under Espresso shot by taste.
Here is lots to play around with. I have had great shots of light roast espresso that ran only 18 seconds to achieve the 1:2 brew ratio. And I had a shots where good taste kept coming out even after 60 grams in the cup with 18 grams coffee in the basket.
Dudley Powel from Horsham Coffee Roaster (UK) also found that running faster shots works better with very light roasts. His recipe is:
18g in – 54g out – 26 seconds
Read his whole blogpost at https://www.horshamcoffeeroaster.co.uk/blogs/news/change-your-roast-profile-or-change-your-brew-method
It all also depends on your equipment. Christian Hansen (Denmark) brew light roasts espresso and he goes for brew ratio 1:2 with conical burr grinders but 1:3 for flat burr grinders. Conical burrs gives a more spread out particle distribution.
Making espresso of very dark roasted coffee seems to be best when it runs very slow and runs thick like syrup.
8. Storage
Light roasted coffee often gets better when rested a bit. For a start 4-5 days. And sometimes light roasts first peak at 3 weeks after roast date. If a coffee do not taste good in the first week – try letting it rest for some weeks.
Boris Lee once had an Ethiopian Gesha Village roast that was flavorless at first. He had given up on it but accidentally tried it after 3 months (stored in a sealed bag) – and then it was much better.
The Danish roastery La Cabra roast very light (no more than 1 minute from First Crack start). They say their espresso roast is best between 30 and 60 days.
Dark roasted coffee (roasted to 2nd crack) is best between something like 2 and 10 days. Later the oils will get rancid = taste bad (well, some people don’t notice this). When you roast to Second Crack the oils will come out. If you stop at the beginning of Second Crack the oils may not be visible right away, but will appear as small wet dots on the bean surface. If you roast longer the beans will be completely covered with oils = look wet. When the oils has come out they are more degraded and exposed – and so they quicker go rancid than in lighter roasted coffee.
But as always; taste for yourself. This is just guidelines to inspire you. Here are lots to explore.
Color scale
In podcast episode 3 we measure the color of the roast on the Agtron scale.
I just participated in a blind tasting of a Colombia bean roasted to different roast degrees/ color:
95 Light – taste: acidic, sweeter, no smoke
85 Medium light- taste: acidic, sweeter, no smoke, not bitter
75 Medium dark – taste: smoke, toast
65 Dark – taste: high in smoke/tobacco, burnt, very bitter
Agtron color 95 and 85 were more alike and clearly different from 75 and 65.
A funny take on the characteristics of different roast degrees
With permission from Jon Ferguson from USA. Follow him on Twitter at ADF2050