The Prufrock Coffee Blog

I scraped through in the heats as last qualifier and am now heading into the finals of the UK Brewer’s Cup.

It will be make or break in the sourcing. We need to choose a grinder and we’ve got to decide what to do about sieving and how modal to go, if at all. We need to choose a water and make decisions on temp, extraction level, agitation and routine shape. So we are taking the Conkers approach. Here are the issues and how we can un-snag them without going round-the-world. (Conkers enthusiasts will recognise certain terms).

Very difficult to get a fresh Ethiopian coffee together for an early April final. Got a tip off about an amazing Ethiopian that Falcon have brought in called Rocko Mountain Reserve 90% or so. Will track its progress but it is set for a mid March arrival. Given the time of year, it might be wise to take a ‘bird in the hand’ approach. The Barn sent out a press release today from Nyeri in Kenya and say mid April arrival. Gwilym is in Panama at Los Lajones and is cupping test roasts against last year’s harvest and reckons the new stuff tastes very green and needs to rest, so as much as I’ve been angling for him to pop some greens in his rucksack for us, it might not be an advantage. Hoff did win the first ever UK Brewer’s Cup at Prufrock with a two day off roast absolutely box-fresh-Reeboks like Kenyan in 2011, but not being a roaster we consider the James Bailey cup-the-night-before-and-keep-your-options-open option the best. We’ve got lots of coffees around and are training up with Bolivians, Brasils, Rwandans and Burundis. We know Colombians are turning up in the next week or so. We’re using [] Mile’s Juan Ticona as a calibration coffee. A dialled-in brew of this should merit above 8.5 out of 10 for everything in the Brewer’s Cup score sheet. So we are waiting to see if something outstrips this.

Me and Jacob Thue and Gordon Howell (who coined the term coffee conkers) have made a coaching team. Gordon is very pro pour-over and loves the Kalita drip. It is an expensive paper, lots of revenue went into developing it. It doesn’t have a seam and there’s the flat bed to give us equidistant paths for the water to draw down. At Prufrock we have tested Clever with V60 papers, Chemex and Filtropa and have discovered the V60 draws down considerably faster. 60 seconds for the V60 and 3 min for the Filtropa even after sieving. We have also part-tasted equal quarters of the draw down of a Filtropa brew. There is a downwards sloping TDS curve that comes back up for the last section presumably due to increased contact time.

Looked in the Cupper’s Handbook and found the term heft. Great term concerning fibre and proteins and how the weight of them feels as you swish coffee around your mouth. I presume there’s a lot more fibre and proteins in an unfiltered cupping but this concept sure helps my scoring for the brewer’s cup body category. I generally prefer the heft of a V60 to our Clever V60 paper method. Bit of an issue there for body points but a longer steep has helped. Prefer the heft of a Woodneck most of all. Tried the Woodneck cloth in the Clever with extraordinary results. It flashed down in 40 seconds but the heft suffered. Missed the waxy body you normally get from a Woodneck. And the brew appeared a little turbid; there were some visible suspended solids. Presumably the sedimentary filtering of the coffee bed is less effective when draw-down passes a certain flow rate; despite the close-knit fibres of the Hario cloth filters this was an evacuation.

Sieving is an interesting one for us. Mr Leighton didn’t sieve for the Birmingham heats and had obvious success. Gordon is very concerned about degassing the coffee excessively if you sieve too vigorously and suggested the shaker approach rather than what I’ve been doing: bashing my 250um test sieve using a big rubber mallet. This needs more investigation. He swears by the 300um Forlife infuser; certainly the best value precision sieve on the market for an even more modal brew than what I’m knocking out.

Conkers training requires you to find an indestructible control test for every brew-method cupping. But the control evolves with each successive cupping. We brew three brews each time but one of them is always made using the same method as the winner from the last cupping. For example, the initial control was my Birmingham heats method. 17-260g sieved Clever, Volvic water, 2min steep 3 min draw dawn with rinsed Filtropa paper. Two cuppings later, Filtropa had lost to V60 papers due to the greatly enhanced acidity range perhaps from a three times faster draw down. Next cupping we tested the evolved V60 control method (V60paper clever) against a pre-infused V60 Clever and the pre-infused method won. Next session we tested waters. A Turkish mineral water with very low TDS but more alkaline at 8pH beat our pH 7.2 RO water existing control and a French water with a high TDS. So the control evolves again. That one needs to be really put through the paces as it was a surprising result.

Next phase is to field test the conquering (npi) control method on the brew bar menu. Let’s say we want to test the Tanzania against our Bunn G2. Alternate the grinders for the same coffee without changing any other variable in the control for a whole day. Take a TDS reading of every brew. Taste every brew. Put the same coffee on the brew bar in opposing methods because we always come back to V60 at Prufrock as the hardest nut to crack (I mean the opposite of that idiom, but you get me;)

The best way to refine a brew method empirically is to pivot off one variable at a time. We consider our scoring data more accurate with consensus cupping like a jury with lots of discussion. The scoring data is only reliable with perfectly dialled in brews so the field testing helps ensure we are on the right grind. As a means of calibration we can return to the original Volvic water control if we lose confidence in the evolved control and we can pick back up on any link in the chain and indeed we should. The more repeats of our testing the more solid our evidence.

If your competition coffee is starring on your brew bar, you are well positioned to compare your evolved Clever Dripper control against a flashy V60. You can even test out flavour descriptors and phrases like “the phosphoric acid tingle of Coca Cola” on your customers. And customers will be able to taste Prufrock’s idea of a competition standard every day. This seems a good training method where a soon to be parent of two can push things forward on 30min a day of training and regular conference calls to Yorkshire. Train little and often and may you head into competition with a ninety-er.