This, shockingly enough, isn’t about espresso.  It is about brewed coffee, and the fact that brew temperature is completely wrecking my head.  We talk a lot about brew temperature but what we are really talking about is water delivery temperature.

I love my Uber boiler, I love the control and the delivery temp stability.  With this, however, has come the painful and embarrassing realisation that it doesn’t matter.  Alright, that is perhaps an overstatement – temperature has massive influence on the quality of the brew, that is undeniable.  I may love the control of the Uber, but having a consistent and controllable temperature really just shifts the problem from the exit spout to the vessel underneath.

Espresso has a rare advantage as, despite being the most finicky and frustrating brewing method, when it comes to brew temperature we can be pretty sure it is close to the delivery temperature.  We’ve enclosed the brewing space and have a lot more consistency that way.  Put a Scace device in and measure and the number you get is as close as we can measure what the coffee would be subjected to during the brewing.  With a french press this is all very different.

Once you open up the brew environment a lot more factors suddenly influence the brew temperature.  The distance from exit to vessel, the temperature of the press itself, the material of the press, the level of insulation, the size of the press and the ambient temperature will all influence the brew temperature: the temperature of the coffee and water as they steep/brew.

In the filter brewing sector/literature we generally see a prescribed brew temperature of 92-96c measured at spray head.  We don’t see much on actual brewing liquid temperature.  Surely a plastic brew basket will create a hotter brew than a metal pan?  Will a recently used hot pan brew hotter than the first brew of the day – despite stable water delivery temperatures?  Is there any research on this?

I’d like to create a few experiments with the Extract Mojo looking at the effect on brew temperature across the brew (though I’d appreciate any help from other people out there?).  Does starting temperature matter more than total temperature spent?  If my brewing vessel radiates heat quicker – because it is wider – can I match a better insulated brew by starting hotter?

I have a few simple experiments in mind that I shall try and perform and post about during the week.  In the mean time any and all thoughts are welcome!

Cindy makes her animals fight for our entertainment

Anette thought the animal crackers were a nice touch and I realised I was drinking my first proper milk drink of the trip!

Then it was time to cup. The open cuppings at Counter Culture have a different approach to most cuppings I have been to. They tend to only cup three coffees, and the discussion afterwards is quite intense with a lot of descriptors going up on the white board.
I agreed with Aaron on my favourite coffee of the three – for me the new Peruvian Valle de Santuario microlot beat out the Rwandan coffee and the Idido Misty Valley on the table. Most people liked the Rwandan Nyakizu, and I can see why – very clean, high acidity (I thought) but still balanced. Amongst the cuppers was Greg Scace, and I confess to getting sidetracked talking about pressure and all things a bit nerdy.

Cupping in DC

Lunchtime!

At the end of the cupping Nick Cho and Trish arrived, but then were hustled out of the room along with everyone else so I could do a phone interview on NPR (which apparently is a big deal around here!) Having not said anything too stupid we headed out and everyone piled into cars and vans to get some lunch at Open City, before eating way, waaay too much gelato (and excellent gelato I might add) at Dulcezza. Rob, the owner showed us the production area and I loved this old bit of kit for making churros:

Old machine for making Churros

Post gelato coffee and lounging around was provided by the Big Bear cafe, and the press of the Biloya there really hit the spot.

The presentation that evening was on a few things – my background in coffee, food pairing and some competition/signature drink stuff. There was a nice crowd and the training centre was beautifully set up (I chose the 3 group FB-80 to play on, over the 3 group Linea…) but still these sort of talks do make me nervous when there are a lot of very wise coffee people in the room. It went pretty well and a fair few people stayed behind after to chat about the sig drinks, more about food pairing ideas or just to talk coffee. Some of the baristas from Easton had made it down so they must have had an overload of my ramblings!

Starting my talk in DC

Not many went out to dinner, and I enjoyed some calmer coffee talk and debate with Nick, Trish and Cindy over some fine Peking Duck.

A quick thank you must again go to the Jensen/Ultimo household for hosting us during our stay in DC – much appreciated. The next morning we headed to Murky Coffee in Arlington for a quick cup and also for me to have a chat with author Michaele Wiseman who joined us for lunch afterwards. Finally the sun came out (until then it had been Londonesque rain) and once lunch was done it was time to hit the road again and head down to Durham, NC and the home of Counter Culture.

Inside Murky Coffee Arlington

Aaron looks especially happy to be in the school photo

People probably want to know how this works and I will try and explain, but I warn you it isn’t massively exciting. As a tester I have no idea how the machines performed. The Scace devices run straight into a datalogger and then into a laptop which is kept out of view. I will never get to see the data, unless a manufacturer chooses to publish. Also a manufacturer will only see their data and not the other machines.

The testing protocol is pretty simple. Each round consists of 14 shots pulled at varying intervals, with the device removed at certain points to simulate grinding, as well as knocking out the puck and flushing. Each machine has four rounds of testing: middle group only, middle group and steaming, 1st and 3rd group only and 1st and 3rd gorup with steaming. With the latter rounds two people worked the machine, even though it was replicating one barista using this. We did this to make sure we could be as consistent as possible in the collection of data across machines. With the steaming we had tested each machine to see the time it took to steam 10oz of milk up to 60C, and then that time was used during the testing.

It hasn’t been the most fascinating testing to watch – every manufacturer was present with a technician during the testing and I think the constant counting down each action, second by second, was close to driving everyone a little crazy!

I think the testing has been very fair, I think the protocols are very good (though I don’t think anyone is claiming that it is beyond improvement). If anyone has any questions I will try and answer them though if you have issues or complaints I am probably the wrong person to speak to. Everyone seems very happy with the fairness of it, which is good.

Next up is grinders which will take a while, and I will write a bit more about that after we have done it.