leon wrote:Is that really true? I usually break the crust and submerge the floating grinds after about 30 seconds on my immersion brews and don't do any further agitation after that until plunging/pulling. Is this not good practice? My cups seem to be coming out fairly well, by my taste.

Not entirely true, no. Immersions plateau quite quickly, especially with a temperature decline, extraction may still rise albeit very slowly, I've seen a 1% rise over 7-8mins after a break & skim. Immersions with fine grinds may not have a significant crust for any period of time. Also, if you're brewing to drink & enjoy (rather than as part of a strict protocol, or in a particular hurry), why break the crust at all early in the brew?

TomC wrote:Problem is (in some cases, not all) it's very easy to have those paper filters clog. The microfine particles suspended in the the presspot (silt and other particles) immediately clog up against the paper during drawdown and you get stuck brews.

As long as the coffee is still warm enough to enjoy, this may not be an issue...~10mins to drain in a Filtropa white paper (my recommendation) has proved OK (for larger brews, you can be drinking a first cup whilst the 2nd still drains), the fact that you have coffee running through the filter & fines can protect against overextraction. Compare pouring liquid & grinds to liquid & holding the grinds back. I usually filter Turkish coffee (gives the coffee a chance to cool too) & have used Chemex, Hario & Filtropa papers with talc like grinds, works OK, prefer the taste of the Filtropa, Chemex next...not keen on Hario for this purpose (but great for actual brewing). Kalita Wave? Forget it, again great brewer, but the flat bed will stall and you'll lose even more coffee.

Paper will shift the flavour slightly, I really prefer to use a Swissgold or Hario Cafeor to filter if grinds are coarse enough, less impact on the taste. I also stumbled on some Irish coffee glasses that are the same diameter as a small press pot - filter into the cup, then insert a Bodum nylon filter into the cup & drink through than too. The fines will usually settle in the cup, as long as you have skimmed/poured of the surface layer (holds a fair amount of silt) you're mainly getting rid of larger particles & chaff.

Is that really true? I usually break the crust and submerge the floating grinds after about 30 seconds...

Good question. I've asked myself the same thing many times. The conventional wisdom is that breaking the crust stops the extraction. James Hoffman has conducted some experiments and concluded: 1. breaking the crust does effectively stop extraction, and 2. most of the extraction takes place in a relatively short period of time, on the order of 30 seconds:

Experiment 2 Conclusions

For me this was really interesting. Even when you got stuck into the break after only 30s you still had a reasonably extracted cup, and waiting a long time didn't mess things up either. Most people are breaking around the 240s mark (though obviously with their chosen grind/extraction preferences).

Most shocking to me was that the break really does seem to stop the coffee extracting further. The TDS of the cups measured 10 minutes after this had barely changed - by 0.01% in most cases.

Here's a link to the blog post:

https://jimseventemp.wordpress.com/2012 ... xtraction/

Thanks for the education! For some reason I had assumed that the grounds weren't extracting properly when they were floating on top, which is why I was dunking them. Turns out the opposite is true. Interesting that I was still getting good cups after breaking the crust after only 30 seconds. I'll try extending that time and see how things change.

No, you're right, when they're floating on top you are not getting the fullest extraction, your target may not be the fullest extraction, but you typically get this by leaving the (relatively fine) grounds to sink of their own accord. This isn't ideal for a cupping specifically as you want to taste the coffee right through the spectrum and need to clear the surface of excessive oils & silt.

If I'm aiming for a ~20% extraction I do 2-4min at 60-67g/l, break & leave til 10 mins. If I'm drinking the coffee to enjoy it I brew at a lower ratio (52-56g/l) & leave for 20-30minutes, (no break at all, just skim off the oils before decanting) this usually gets me to ~23%, which is my preference for high sweetness. You may hit this range in less time with a very, very fine grind but the particles won't have settled out of the way and you'll get bittering quinic, pruney or paracetamol-like flavours.

leon wrote:Thanks for the education! For some reason I had assumed that the grounds weren't extracting properly when they were floating on top, which is why I was dunking them.

Well, that would be true if the are grounds weren't evenly wetted. You can see Sarah Anderson's routine here (skip ahead to around 3:15:00):

http://livestream.com/SpecialtyCoffeeAs ... s/64321860

She pours most of the water w/ a "bulk kettle" then tops the brewing vessels up with a gooseneck kettle. You can tell that she's concerned about whether the grounds are evenly wetted, because she goes in with a spoon to pat down the grounds very early in the brew cycle. Then she leaves the coffee alone until she breaks the crust.

What I've found at home-where I am using a gooseneck kettle and narrow brewing vessel-is that there is no need to pat down the grounds. I can move the kettle around, delivering the water in a circular stream. That way the grounds are agitated and evenly wetted during the pour.

This brewing method is a great competition strategy in part because Sarah could focus on the judges and still get very consistent results in the cup. (Plus, the judges probably cup a lot of coffee and appreciate that aspect of the routine.) By the same token, this is a nice brew method if you need to multi-task in the morning. One I get a brew started, I usually feed the dog and prep a shot for my wife's cappuccino. Then I break the crust, scoop of the oils and decant the brew into the filter. By the time I have served my wife her drink and cleaned up the espresso machine, my paper-filtered immersion-brewed coffee is waiting for me. Bob's your uncle.

I still brew by a lot of other means, but usually when I have more time or just want the coffee extracted directly into a cup.

So much good information in this thread already.

Am going to start experimenting with Sarah's technique tomorrow..

Question: start with a pretty standard cupping grind ?

Yes. Most coffees do seem to prefer a coarser grind setting with this brew method, as compared to a V60. But it's not necessarily a big difference. The settings might be a macro step apart on the Vario, but the grinds probably aren't noticeably different to a casual observer.

You'll know the sweet spot when you find it. When in doubt, do the Perger shuffle:

I want to run something by you guys.

I buy my coffee roasted to order, opening a bag at 2 to 3 days post roast. Noticed every mind-blowing cup I extract falls on the first day. In fact, all the cups on the first day seem to be pretty awesome.

Coincidence, or does roasted coffee degrade that quickly, and I'm trying in vain on days 2 through 5 to extract something as dynamite as day 1?

P.S. - Tried a couple 'polished immersion' brews as outlined in this thread somewhere. I can see a lot of potential with this method, but still not hitting the mark for me. Not sure where I'm going wrong with those but will forge ahead.

At least now I know what to call it:

http://dailycoffeenews.com/2015/05/25/a ... -brew-bar/

Coincidence, or does roasted coffee degrade that quickly,

That rings true to me. I've never had much use for "resting" coffee, certainly not for brewing. The fresher the better. I seem to recall Jim Schulman recommending a higher dose and coarser grind as espresso ages. Maybe the same thing works for brewing?

Here's a step-by-step breakdown of the polished immersion brewing process I use:

http://www.coffeebos.com/step-by-step-p ... n-brewing/

Anyone can adapt this recipe based on the equipment they have on hand.