Matt Perger - Reddit AMA brewing discussion

#1: Post by **TomC** » May 20th, 2015, 3:49 am

Matt Perger answered questions and shared some of his opinions on brewing and roasting on reddit /r/coffee a few days ago. I remember seeing the heads up about the date, but didn't see it till now. It was a popular and friendly discussion with some notable observations or approaches that Matt favored that are out of vogue with many today, but certainly have come up in the past. I like and appreciate his willingness to do things just to experiment and examine, even if it's 180° opposite of what others say to do. The conversation can be seen here.

A couple interesting points, he advocates manual brewing only with vigorously boiling water, no qualifiers, exemptions, etc. BOILING water. Lots of agitation too.

He advocates sieving only to remove the larger spectrum of particles, completely unconcerned with fines. He'd like to go back and create a competition presentation using his newest methods, versus his original 2012 Brewers Cup competition where he sieved fines out of the grinds and instead sieve out the boulders.

While I don't tend to agree with anyone 100% when it comes to coffee/roasting/brewing (subjectivity and personal tastes and all), I find his talk was quite good and useful. He seemed to frame the discussion in terms of "this is what I like and what works for me" as opposed to "this is the best way to do this". I've disagreed with some of the things he's written in the past, but that pertains to roasting and mostly pertains to jargon and not directly tied to brewing. My point is, I deeply respect and appreciate his work, even if I don't jump on the same fan-boy-ish wagon and worship everything he says, like many are prone to do. He's earned his place in the odd spotlight that is our coffee world and I imagine his efforts will in some ways continue to improve the coffee experience of many.

My own observations in the past with boiling water led to astringency in the finish. Obviously, it would increase extraction, but I'm not sure if that is the answer in every case. I've sieved above and below a desired screen size in the past, but still personally tend to just sieve and remove as many super fine particles, especially in bright, dynamic coffees that already display enhanced flavor separation (I attempt to push it more so in that direction). I generally am not concerned with "boulders", but both my Ditting 1203 in the past and the Bunnzilla with Ditting burrs have always seemed to give me a very even grind but away from them, the bell curve widens. What I need to do, before formulating a hard opinion on sieving "boulders" is to set up some blind testing first, controlling only for that, and see what I get. I have a suspicion that he could very well be correct and that we might fool ourselves into thinking that our cups are fully developed and not tainted even slightly, with sour, undeveloped notes, but when compared to a higher extraction of a more even grind bed, it should become more apparent.

If anyone else has followed along or has any opinions, I'd love to hear them as well.

#2: Post by **canuckcoffeeguy** » May 20th, 2015, 8:33 am

When he advocates for boiling water, is that for any roast level? Or, just very light roasts?

May 20th, 2015, 11:55 am

He's a bit cryptic in that regard. I think he's only using it for his own roasts from Sensory Lab / St. Ali, which are "light but developed," probably around Heart's roast level? I haven't been able to try the roasts, so I can't say.

Personally, I've moved up to boiling or near-boiling for immersion following a long trend in that direction. From cupping at 200 F to 202,203,204,205,207, and now 210 or so. It's amusing that the Aeropress comes with directions to use 180-190 F water when I've been getting the best results from it at 209-210 F in the past few days

I can't get pour-overs to not taste burned beyond 205-206 F regardless of roaster. There are some roasts that I simply can't brew as a V60 past 201 or so, but that's due to roaster's "error" (to my palate, I assume intentional on their end). I'd be curious for suggestions from anyone who's able to brew pourovers with boiling water.

May 20th, 2015, 12:47 pm

I get very good results doing v60 pour-overs of my own brewing-focused roasts between 205F and 209F in the kettle. (These are city roasts, usually in the range of FC-start-temp + 17F, +/- 2 degrees or so. I've never tried doing a boiling water pour-over, but I suppose with a coarser grind it could work well (especially if you also use the microwave trick). Keep in mind that temperature should drop about 5-6F as the water flows down the spout and falls through the air, and that the coffee mass itself serves as a heat sink, lowering your slurry temperature quite a bit.

For comparison purposes, most of my immersion brewing happens at lower temperatures -- standard starting points would be 205F for cupping or glass-walled press, 202F for insulated presses, 202F for syphon pots (with a much shorter steep due to the inherent agitation). Of course, doing any comparisons of this kind without also referencing differences in grinder and grind setting doesn't tell us very much, as one can make a great press using fine grinds and lower temperatures, or coarser grinds and higher temperatures. What will be best will depend significantly on the properties of your grinder. If I was trapped with nothing but a kettle, a porlex and an aeropress and wanted to brew the best cup possible, I'd grind quite fine and brew at a low temperature, given that a tight grind would be much more even on that grinder than a coarse grind. I'm not sure I've fully adjusted to what my Mini-Bunnzilla is capable of in the coarse range, so maybe I should start experimenting with coarser/hotter for immersion as well. This reminds me of Marshall Hance's recent advocacy of a "grind coarser, then extract harder" approach because high quality grinders yield tighter distributions in a coarser range.

I also agree with Perger that some thorough agitation in the beginning of a v60 brew is desirable, at least when brewing single-cup quantities. It lets you slow down flow rate without having to grind finer, and ensures even wetting.

#5: Post by **Bluecold** » May 20th, 2015, 1:10 pm

When starting with boiling water in a gooseneck kettle and using a Kalita Wave, I got a 93 degrees C slurry temperature during almost the entire 3.30 extraction.

May 20th, 2015, 2:14 pm

Do you think that ~7C drop is standard across the typical range of brew temps? If you started at 95C, do you think the slurry in a Kalita 185 would stay at 88C during an entire extraction?

This is interesting, and much more of a drop than I would have expected. How did you measure this?

May 20th, 2015, 2:34 pm

Out of curiosity to see what would happen when taken to such an extreme, I just made a siphon of the pulp-natural Tanz PB that we are playing with in this month's R&L thread. I took it to an extreme by getting the upper boil to a rolling boil and holding it steady for a minute or so before adding the coffee, which was ground more coarsely than usual on the Mini-BZ. Slurry temperature declined to 208F fairly rapidly and then remained steady until I terminated the brew. I held brewing time down to 2 minutes and 5 seconds, to avoid over-extracting. The resulting cup was balanced and did not taste burned or bitter. Compared with cups I've made in the normal SCAA temperature range, it was sweeter and fuller-bodied, with the acidity less focused, and with more astringency in the aftertaste.

I could imagine some people preferring this to my standard brews, which tend to be brighter and clearer, and mellower in the aftertaste, but a bit less sweet and full. But personally, I doubt I'll repeat this with any frequency, unless I'm trying to tame an underdeveloped roast.

#8: Post by **yakster** » May 20th, 2015, 2:54 pm

Interesting experiment in light of Matt's response to a question about Matt's focus on solubility and sweetness over flavor and clarity.

I suspect that you, and many many others may perceive underdevelopment and sourness as positive flavour, clarity and acidity.
This is -of course- my personal opinion.

I do taste astringency in hotter brews which I consider over-extracted, but may be someone else's preference.

May 20th, 2015, 3:08 pm

Yes, and we should keep in mind that calling a brew over- or under-extracted is a normative judgment not an objective one. So perhaps a less loaded way to phrase his statement would have been "some people may prefer brews that I would consider under extracted, finding them clearer or brighter."

#10: Post by **MWJB** » May 20th, 2015, 3:10 pm

Scott Rao has written about the expected temperature drop in drip brewing, also recommended boiling water at pour. Prior to that MIT carried out experiments on behalf of the CBI, also listing expected drop of brew water temp when coffee was added to water held at a constant temp.

All the CBI's brewing advice offered to home users referred to bringing the water to a rolling boil, for drip "still boiling water" to be poured directly onto grounds.

If your slurry temp is targeted at 93-94C, with a 6-7C drop between kettle & brewer, there don't seem to be a lot of options other than boiling water. SCAA home brewer certification recommends it's brew temperatures at the point where the water contacts the coffee.

I guess it also depends on how much heat your coffee & brewer are going to eat up, e.g. a thick glass/ceramic vessel will steal more heat than a thin walled glass or steel vessel?

There always seems to have been a certain amount of misinterpretation as to what brew temps are ideal, but as long as you know what you have you can explore them.