PUCK PREPARATION TOOL

THE HOG

AN OTHER EXAMPLE OF HOW THE DECENT ESPRESSO MACHINE CAN

HELP UNDERSTAND HOW ESPRESSO WORKS!

STÉPHANE RIBES –JUNE 2019

THE HOG –SUMMARY

Benefits

•Reduced edge channeling

•Quicker wetting of the coffee puck →More even preinfusion & extraction

✓reduced temperature gap between top and bottom grinds

✓lower concentration gradient of the extracting fluid between top and bottom grinds

✓reduced negative impacts of slow preinfusions

✓less puck compression with high preinfusion flow rates

•More stable pressure (flow profile with constant flow)

•Smoother evolution of the extraction yield →better control of the extraction in the typical range of

brew ratio, when reaching the highest possible extraction is not the most desirable objective

Additional information

•Requires a finer grind

•Represents an additional step in the puck preparation (does not replace grinds distribution)

•First introduced by Barista Hustle (Matt Perger) in 2017:

http://community.baristahustle.com/t/lets-talk-about-the-hog/2000

•The 2 hog tools I tested were inspired by this work; they were designed and manufactured by

Joachim Morceau (and his lovely wife), French barista –formerly head Barista at Terres de Café

and now owner of the Substance café specialty coffee place in Paris

•Tool principle: before tamping, form vertical canals in the coffee puck to create “controlled channeling”

•Tool description: - 95 steel spikes stuck and glued in a 3D printed base

- Designed for VST 20g+ baskets

-2 versions: 0.8 mm diameter spikes (“thin” Hog) and 1.1 mm diameter spikes

•In the experiments reported in the first section of this document (full flow priority profiles) the hogs were used

in combination with a 55 mm diameter paper filter underneath the coffee puck

•The test with 9 bar extractions were performed without paper filter

THE HOG –DESCRIPTION

THE HOG –IMPACT ON EXTRACTION (1/2)

•Effects of the hog tool on pressure evolution during espresso extraction (flow profile)

•Grind setting was adapted to reach a comparable pressure peak during extraction

•Much finer grind is needed with the “thick Hog” (EK1.5, from EK2.2 with no hog)

•Quicker wetting of the coffee puck with hogs, earlier first drop in cup

•Slower rates of pressure rise and decrease with hogs –more stable overall extraction pressure

•Intermediate intensity of all recorded effects with the thinner spines

Dry Camlab filter below puck

(no hog –EK2.2)

Dry Camlab filter

+ “thin” Hog (EK1.9)

Dry Camlab filter below puck

(no hog –EK2.2)

Dry Camlab filter

+ “thick” Hog (EK1.5)

First drop in cup with hogs: 12 s

Without hog: 14 s

0,00

0,05

0,10

0,15

0,20

0-10 mL 10-20

20-30

30-40

40-50

50-60

60-70

70-80

80-90

90-100

EXTRACTION (g/mL)

Camlab filter - no Hog Camlab filter + thin Hog Camlab filter + thick Hog

10%

16%

19% 21% 22% 23% 23% 24%

14%

17%

20%

24% 24%

12%

16%

18% 20% 21% 22% 23%

10%

15%

20%

25%

10 mL 20 mL 30 mL 40 mL 50 mL 60 mL 70 mL 80 mL 90 mL 100 mL

EXTRACTION (%)

Camlab filter - no Hog Camlab filter + thin Hog Camlab filter + thick Hog

THE HOG –IMPACT ON EXTRACTION (2/2)

•Effects of the hog tools on extraction evolution

•Flow profile, 19 gram dose

•For each shot, the output was split into 10 portions

(every 4 s after first drop)

•Thanks to the flow priority extraction (2.5 mL/s)

all samples had comparable volumes

•Coffee extraction is performed more gradually with the hogs

Typical brew ratio zone

(2.1 –2.6)

THE HOG –DETAILED TEST PROCEDURE (1/2)

•Decent Espresso Machine DE1PRO v1.1 with IMS SI 200 IM shower screen (i.o. stock IMS CI 200 IM)

•Mahlkönig EK43 S grinder

•Montille water (Le Mont Dore, France –low mineral content)

•19g of The Barn La Laja coffee beans (filter roast) ground in a 22g VST basket

(roasting date: 16/05/2019 –vacuumed and frozen on 10/06 - Tests made on June 16th and 17th)

•Beans were ground frozen in a double wall stainless steel cup

•WDT in the cup with a mini whisk

•55 mm diameter Camlab paper filters below the coffee grinds –no preliminary wetting of the filter

•WDT in the basket with a mini whisk –gentle raking of the puck surface with the hog –no taps

•Hog tool in and out of the puck

•Manual tamp with a 58.6 mm tamper

•TDS measurements: Atago PAL zeroed with Montille water –no additional filtering of the coffee samples

–dilution (ca. x2) of the 3 first samples from the sliced extractions (to avoid device saturation) –all

samples measured at room temperature after thorough agitation –1 data point = average of 4 to 6

measurements of each coffee sample

THE HOG –DETAILED TEST PROCEDURE (2/2)

Montille

TESTS WITH PRESSURE PRIORITY

EXTRACTION PROFILES

•“E61 CLASSIC” (STRAIGHT 9 BAR PRESSURE)

•ADVANCED PREINFUSION + 9 BAR PRESSURE

•THESE 2 NEW SETS OF TESTS WERE COMPLETED WITHOUT PAPER FILTER UNDERNEATH THE PUCK

THE HOG

STRAIGHT 9 BAR EXTRACTION

No hog tool –EK2.3 Thin hog –EK2.3 Thick hog –EK2.3

EY 19.8% EY 19.3% EY 19.0%

11s 17s 23s

11s 17s 23s 11s 17s 23s 11s 17s 23s

THE HOG

STRAIGHT 9 BAR EXTRACTION

Observation and measurement results (extraction curves + videos) –with the hog tools:

•Slightly delayed pressure rise but no visible impact on the extraction time

•Altered flow evolution in the cup: higher flow rate first, then lower flow

•Less turbulences and sprays at the exit of the basket

•Lower extraction yield

•All these effects are more intense with the

“thick” hog (1.1 mm spines)

Taste results

•Very sour taste with no hog (“channeling taste”)

•Better taste with the thick hog (less sour)

•Significantly improved taste with the thin hog

(much more sweetness)

•Longer extraction time with no hog (not tested) may

have led to better taste results (less sour)

No hog

Thick hog

Thin hog

Taste

(subjective scale)

Extraction yield

19.0

18.0

20.0

19.0

19.3

19.8

THE HOG

ADVANCED PREINFUSION AND 9 BAR EXTRACTION

No hog tool –EK1.6 Thin hog –EK1.6

Thick hog –EK1.45Thick hog –EK1.6

•Earlier first drop in the cup

•Quicker extraction, especially with

the thick hog (finer grind needed

to compensate)

EY 19.8% EY 19.5%

EY 18.7% EY 19.0%

2 2

THE HOG

ADVANCED PREINFUSION AND 9 BAR EXTRACTION

Observation and measurement results (extraction curves + videos) –with the hog tools:

•Earlier first drop in the cup and shorter extraction times

•Lower extraction yield

•All these effects are more intense with the

“thick” hog (1.1 mm spines)

Taste results

•No hog: acceptable balance of acidity, sweetness and

astringency –very nice mouthfeel

•Better results with the thick pins hog (more sweetness)

only after adjustment of the grind setting

•Significantly improved taste with the thin pins hog

(much more sweetness and fruity taste)

No hog

Thick hog

(finer grind)

Thin hog

Taste

(subjective scale)

Extraction yield

19.0

18.0

20.0

19.0

19.5

19.8

Thick hog

(no grind

change)

18.7

THE HOG –DETAILED TEST PROCEDURE

(TESTS WITH PRESSURE PROFILES)

•Decent Espresso Machine DE1PRO v1.1 with IMS SI 200 IM shower screen (i.o. stock IMS CI 200 IM)

•Mahlkönig EK43 S grinder

•Montille water (Le Mont Dore, France) –adjusted to SCAA with sodium carbonate and Epsom salts

18.5g in a 22g VST basket

Target: 42g out

Straight 9 bar profile

(July 13th)

Advanced preinfusion and 9

bar extraction (July 14th)

Beans from

Friedhats Coffee

Roasters

Kochere Boji

(natural Yirgacheffe)

Las Margaritas (washed

Colombian Pacamara)

Roasting date

01/07/2019 18/06/2019

Vacuumed and frozen

07/07/2019 27/06/2019

•TDS measurements: Atago PAL zeroed with SCAA water –no additional filtering of the coffee samples –all samples measured at room

temperature after thorough agitation –1 data point = average of 3 or 4 measurements of each coffee sample

•Beans were ground frozen in a double wall stainless steel cup

•WDT in the cup with a mini whisk

•WDT in the basket with a mini whisk –gentle raking of the puck surface with the hog –no taps

•Hog tool in and out of the puck (hog stand to ensure a straight vertical movement)

•Manual tamp with a 58.6 mm tamper

THE HOG

ADVANCED PREINFUSION AND 9 BAR EXTRACTION