(GPGT)Espresso machine hoot

[Lazy_Tiger]

All this science vs tongue talk, btw have you guys seen this interesting video by Ben Kaminsky where he probably piss off a lot of top baristas and roasters.

He talks about most cafes are underextracting their shots. His simple solution is to just let the shot run longer instead of cutting it off early.
At about the 1:05 mark, he talks about separate roasting each coffee to their specific peak b4 blending them, as oppose to what many roasters are doing, which is blending the greens first then roasting. The woman questioning him shortly is Trish Rothgeb of Wrecking Ball.

He firmly believes good coffee can be achieved by using the correct tools and accurate measurements. And that good quality coffee isn't subjective and shouldn't be based on individual taste.

Same as the matt perger and scott rao and James Hoffman camp. 20% extraction yield seems to be what they agree is generally the best for balance of sours and bitterness. 30% of the weight in the bean is the max extractable soluble solids while the rest 70% is cellulose.

However I still think that 20% should not be taken as a hard guide and in the end it still depends on what the barista whats to showcase in the bean. If getting 20% extraction results in masking certain floral aromas in geishas than that defeats the purpose of using geishas in the first place.

Here James Hoffman talks about a "double hump, " when he talks about what he thinks he gets at different extraction ranges.
http://www.jimseven.com/2010/11/08/the-double-hump/

I think the vst tools are great for consistency and give a good measure of what is done wrong or right. Extremely low or high extractions should be avoided because clearly they taste bad but as we go into mid ranges of extraction (18-21% perhaps) ultimately taste profile should be determined by the end user.


I think alot of cafes are underextracting because of high dose and channeling. High dose and channeling can result in an odd tasting espresso of extreme sourness and bitterness and lacking the smooth caramels of mid extraction. With a 22g basket sadly I will get channeling all the time unless i use WDT and nutating. High dose is very hard to master but taste fantastic when used with the correct (usually light roasted) beans.

 

[chikyblink]

I have a question regarding light/dark roasts and dosage. This is what I understand so correct me if I'm wrong.

Dark roasts: easier to extract
Light roasts: harder to extract

Higher dose: requiring coarser grind
Lower dose: requiring finer grind

So if lighter roasts are harder to extract, aren't we suppose to grind them finer to aid extraction, thus requiring a lower dosage?

 

[Lazy_Tiger]

As for percolation time, time is not an independent variable but rather the result of the other parameters.
Like i mentioned previously, grind, pressure, temp, tamp all play a part.

This is universally agreed.

At higher temperature, it does bring along more flavours, but as well its bitter substance, which does affects the overal sensory appreciation as the bitterness will overwhelm certain delicate notes.
Thus there's no clear ruling going high is right. It's not about the solids, it's also about the lipids, volatile aroma, carbo, etc.
And espresso are highly not recommended to be extracted abv 92 degrees, unless a few conditions are met.

How high you set the temp depends on the roast level and the bean. Dark roast, low water temp. Light roast needs higher temps. Higher temps doesn't necessary extract out the bitter undesirable compounds. Lower temp can also do this simply by running the extraction for too long, using too little grounds and grinding too fine. Higher temps are used for light roasted coffee because you need higher energy to dissolve the coffee solubles which are hard to extract from a light roasted coffee with less porous cell walls.

As for your definition of over extraction due to more extraction volume, i don't really agree because it's not considered that way. It won't burn the coffee as a real overextracted coffee do. By a more commonly known espresso, over extracted espresso may have white foam with big bubbles, if water temp was too high, a white spot can be found in the middle of the cup.

Wait...I didn't "define" overextraction by more volume of espresso...If this was the case the an all filter brews are overextracted. Overextraction defined when you have extracted out the undesirable bitter tasting compounds that usually happens toward the tail end of process and this is usually more than 20% of the extraction yield (did you really read Scott Rao's books?). Like I said hot water thru coffee doesn't "burn" any of the oils. I wonder where you get this idea from. This only happens if you reroast the coffee again. The oils can oxidise with heat but it takes a long time. So by pulling the shot too long you will start to also dissolve the bitter compounds that only dissolve later. Taste the last 5s of an espresso shot and you will find its more bitter than the 1st 5s.

As for extraction standards, it depends on where you come from.

Preferably getting 25ml in 25-30 seconds in Southen Europe which includes Italy, Spain, Greece, etc.
In fact it was 6.5g +- 1.5g, 90 +-5 degree c, 30+- 5 secs.
There's no certain criterion but consunsus on a percolation time is in the optimal range of 25-35ml. Volume again depends on the preference.

There is actually a defined standard for italians. and while u say vol depends on preference this is tricky and pretty useless because it really depends on the crema which has a mind of its own.


http://www.espressoitaliano.org/files/File/istituzionale_inei_hq_en.pdf

Northern Europe like Germany Holland, Scandinivia and USA are the ones who may ask for up to 70-120ml.

This is pretty much and cafe crema and undrinkable without sugar or cream. Germany and holland is not northern europe and high vol espressos are more due to the presence of crappy super autos / nespressos there probably originating from switzerland. Ristrettos and smaller espressos are pretty much the standard in good US cafes actually.

However short below 10 secs extraction, though most crema out first, is considered under extracted, tasting dull and diluted.

End of the day, the most important chapter i learned is not the science. Is the psychology of perception.

Agreed. 10secs is likely nasty but diluted? THis depends on your dose or how fine u grind. Its most likely very sour but certainly not dull.

Yah the customers perception is important. Thats why starbucks and some italians (illy, lavazza) can still continue to sell crappy coffee by claiming a certain image or selling $20 for a fancy tin of old coffee.

 

[Lazy_Tiger]

I have a question regarding light/dark roasts and dosage. This is what I understand so correct me if I'm wrong.

Dark roasts: easier to extract
Light roasts: harder to extract

Higher dose: requiring coarser grind
Lower dose: requiring finer grind

So if lighter roasts are harder to extract, aren't we suppose to grind them finer to aid extraction, thus requiring a lower dosage?

Generally yes. But if the flavours in a light roast are so delicate and mild (less starch,sugar, fats converted into caramels in the roasting process) and using a low dose will result is a weak bland coffee then this can be compensated with a high dose, higher temps and using VST baskets to aid extraction and get a punchier and yet still balanced flavour profile. (This is what alot of 3rd wave try to do. See Squaremiles recommendation for their usually light roasted red brick).

Ultimately it depends what the roaster wants to showcase. Some wants to highlight the high acidity fruit flavours of the coffee and will recommend high doses, low temps but may not be to personal preference.

Honestly this is use a rule of thumb. Best to check with the roaster on his recommendation and what to look out for in the flavour profile.

 

[Sylar22]

29g of espresso weight for a 40ml shot (including crema) is pretty reasonable. Too high volume (60ml) for a 30g shot could mean water to hot or robusta or coffee roasted within 24 hours. To low volume could mean coffee is too old, water/machine is too cold or the dreaded channeling. But I would say don't bother with the crema too much as a measure of what is good. Best to tell is from the taste and smell.

Let me try to pull at 28g espresso from 14g dose and see how it taste like compared to the 40g espresso i normally pull. Normally i mix it with milk to make latte so i'm afraid 28g (which is very little) of espresso might be overwhelmed easily by the milk.

 

[compuser]

I have no problem with 30ml from a 12 gram shot.

Your coffee plays a bigger part.

 

[chikyblink]

Home Roasting on a popcorn popper(update2)

Today I pulled some shots of the Santos I roasted on Tuesday. The 2 batches which I stopped roasting at the 7th min mark tasted bitter and burnt, even with tight ristrettos. But surprisingly, they taste ok with milk, almost chocolate-milk-like.
The last batch which I ended 30secs earlier is my first drinkable straight shot. Although still a little too dark which burnt away most of the flavors, at least I didn't spit it out like the rest.

Moving on, I shifted my setup from the living room to my own bedroom, right at my window. I also stuck a thermometer(which finally arrived from amazon) in to monitor bean mass temperature.

A 6meter extension cord is used instead of straight from the wall. With a fan at max aimed at my popper sharing smoke and chaff with my neighbours, I was ready to go.

I again roasted 3 batches today. 70gm, 80gm and 120gm.

70gm
I again did the on/off thingy every 20secs in attempt to stretch out the timing to 1c. After it reached 150°C or so, I stopped doing the on/off thingy and just let it auto pilot. Surprise surprise, 1c happened at the 4:30 mark at 200°C instead of my usual 3:20. Looks like the extension cord worked after all. I waited for 2c but it seems the temperature maxes out at 210°C. I decided to call it at the 12th min mark and dump the beans.

80gm
I reckon the temperature couldn't get high enough coz there were too little beans in the chamber causing too much air to escape. So I decided to increase the weight a little.
Did my usual on/off thingy. This time 1c happened at the 5th min mark. But alas the temp stalls out at 210+°C again. I let it run till the 13th min mark b4 dumping.

120gm
This time I whacked 120gm. Greens totally didn't move at all at the start so manual stirring is required. 1c happened a little quicker at 4:20. Max temps did increased a little but never really reached 220°C. At the 9th min mark I thought I heard 2c so I quickly dump it out.

They looked very similar in terms of color but the 70gm batch smells the nicest.

All packed up to degas

Today's batches look very promising. I probably couldn't wait 3-4days. I'll taste them tmr!

 

[erwinseow]

Hi there. A very newbie here. Your picture of the roasting machine looks dangerous as you put it is surrounded by cupboard boxes. If the machine catches fire... it looks quite dangerous. Try looking for enclosures that are non flammable. Maybe a metallic dustbin or something.... Better be safe than sorry.

 

[chikyblink]

thanks for the heads up. rest assured that I'm constantly finding ways to improve my setup.
as for the cardboard box, do you guys think it's safer to cover it with aluminium foil?

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[Sylar22]

Just pulled a 15g dose shot into 1.5oz(42ml) volume and 31g weight liquid espresso with a time of 27.94s. Tasted a bit sour and acidic, flow was dripping and not flowing smoothly. Might be because grind is too fine or dose is too much,but i read that for coffee to be sour and acidic it's mainly because grind is too coarse and dose is too little, totally opposite of what i have experience? Any idea what might have went wrong. Anw just a quick qns, do y'all do a double shot into one cup or seperate into two cups coz normally i do a double shot ~15g straight into one cup.

 

[n0d3]

All this science vs tongue talk, btw have you guys seen this interesting video by Ben Kaminsky where he probably piss off a lot of top baristas and roasters.

He talks about most cafes are underextracting their shots. His simple solution is to just let the shot run longer instead of cutting it off early.
At about the 1:05 mark, he talks about separate roasting each coffee to their specific peak b4 blending them, as oppose to what many roasters are doing, which is blending the greens first then roasting. The woman questioning him shortly is Trish Rothgeb of Wrecking Ball.

He firmly believes good coffee can be achieved by using the correct tools and accurate measurements. And that good quality coffee isn't subjective and shouldn't be based on individual taste.

Yeah, I saw this a while back. He was in Singapore for a while consulting for a certain company cough. I daresay he's THE guy if you want to talk to someone about coffee and where it's heading. He isn't a good speaker though.

 

[chikyblink]

interesting... which company is it?

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[Lazy_Tiger]

interesting... which company is it?

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Oriole. They had a revamp of their company. maybe things was getting stagnant. I think Matt Perger helped too. I just tried their espresso today (raven) i think and its more agreeable to my tastebuds. not as bitter and dark as previously.

Nod3 you sound like you work in the industry?

 

[Lazy_Tiger]

Just pulled a 15g dose shot into 1.5oz(42ml) volume and 31g weight liquid espresso with a time of 27.94s. Tasted a bit sour and acidic, flow was dripping and not flowing smoothly. Might be because grind is too fine or dose is too much,but i read that for coffee to be sour and acidic it's mainly because grind is too coarse and dose is too little, totally opposite of what i have experience? Any idea what might have went wrong. Anw just a quick qns, do y'all do a double shot into one cup or seperate into two cups coz normally i do a double shot ~15g straight into one cup.

Sour espresso can be due to many reasons but generally:
1) Under-extraction - Under extraction can be due to...Too high dose, too coarse grind, extraction time too fast, water too cold. The variables interact with each other so its hard to pin down. Further more if extraction is uneven (uneven puck, puck hitting the shower screen when locking in etc etc) its makes it even more complicated.
2) under-roasted
3) Natural inherent characteristic of the bean

There is always some sourness/acidity in coffee to balance with the bitters and add some life to the caramels but if you like something less sour then maybe brew at higher temp or pull a longer shot (35s) or use VST basket.

Does your machine have some kind of preinfusion?*may need to brew longer if so.

Double shot into 1 cup. 2 cup standard is a relic of old italian style of brewing where they use 7g of coffee to get 25-30ml vol.

Also cups REALLY matter to the overall experience. I go for unheated white porcelain. Easier to see the viscousity when the crema sticks to the walls of the white porcelain.

 

[Lazy_Tiger]

They looked very similar in terms of color but the 70gm batch smells the nicest.

All packed up to degas

Today's batches look very promising. I probably couldn't wait 3-4days. I'll taste them tmr!

Wow you are really organised with the chart and to get the correct profile. Did you taste using espresso or filter? can try cupping method too to evaluate bean quality.

 

[chikyblink]

espresso only... the best extraction method remember? lol

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[n0d3]

Oriole. They had a revamp of their company. maybe things was getting stagnant. I think Matt Perger helped too. I just tried their espresso today (raven) i think and its more agreeable to my tastebuds. not as bitter and dark as previously.

Nod3 you sound like you work in the industry?

Yeah they invited MP as well. To be honest Oriole never really struck me as speciality ever since Keith left. Plus the new logo seems really messy...Jewel is also trying to revamp itself, I think they started to roast again (heard rumours they were just repackaging coffee). Then again I'm really biased so...hahaha. :X

Cannot confirm nor deny HAHAHA. Cannot sexpose myselfffff.

 

[Lazy_Tiger]

Yeah they invited MP as well. To be honest Oriole never really struck me as speciality ever since Keith left. Plus the new logo seems really messy...Jewel is also trying to revamp itself, I think they started to roast again (heard rumours they were just repackaging coffee). Then again I'm really biased so...hahaha. :X

Cannot confirm nor deny HAHAHA. Cannot sexpose myselfffff.

Oh I thought Keith was the boss. Today's papers mention many cafes closed over the past 2 years. Really not easy to run a cafe...I think too many jumped on the bandwagon after the success of the few pioneering ones.

 

[n0d3]

Oh I thought Keith was the boss. Today's pap papers mention many cafes closed over the past 2 years. Really not easy to run a cafe...I think too many jumped on the bandwagon after the success of the few pioneering ones.

Oriole now owned by Far East. I think Keith still has a stake in it but he's not involved with the company that much.

Ya not easy man...Singapore too saturated and the skill level of our service staff is a joke (I think partially cause it's not seen as a career and the pay is too low). Most of the cafes I go to have nothing special to offer and they can't do simple things well. Unless you have a very niche product, it's hard to survive in FNB.

 

[Lazy_Tiger]

The feldgrind is finally here! Solid built quality and well designed. pulled a 1st shot at their recommended setting and the pour came out perfect! 18g dose for a 30g shot.

Look at the pour!

There are some cons though. Not as easy and fast to grind as the HG One. The setting is also very sensitive. The HG one is more forgiving, 1-2 notches on the setting dial hardly makes a difference to the pour rate. For the feldgrind I got a gusher just by turning the dial by 1 number from an acceptable setting. Are large conicals more forgiving? I don't think so. I think the smaller turning radius of the setting for smaller grinders makes small adjustments more exaggerated in their effect on the grind size.

Overall a value for money product for 200 bucks. Highly recommended if you don't mind the long wait and non existent customer service. Makes a good portable grinder for outdoors, camping or on the move, small and rock solid. Beats the porlex to pieces in terms of build and grind consistency. Pair this with a v60 and good beans and you are good to go!