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Espresso

• With Decent Pro 1.45 + Niche
• With Breville 876 + Niche
• With Breville 876 + Dose Control

Highly Recommended

• Philocoffea 229,231,237: (fast degrade)
• Cafe Bach パナマ ドンパチ ティピカ
• Methodical Repose Decaf

Dialing In

Keep a proper dose so that after pre-infusion the puck still has a small gap to the group head.

When dose and yield are fixed:

• Grind finer: more extraction, more bitterness, less acidity. Higher risk of channeling.
  • Flow rate usually gets smaller when grind finer.
  • Flow rate usually gets bigger when grind coarser. But when it is too coarse, the flow rate changes insignificantly. The espresso usually tastes worse at such range.
• Higher temperature: slightly more extraction, less emphasized acidity, more sweetness.
• Higher pressure: slightly more extraction, less emphasized acidity.
• When grind coarse enough, the variating pressure/temperature profile might not have enough time to implement the variation.
• When the thickness is good but there is a little bitterness, if a flat pressure leads to a consistant raising flow rate, it could extract less in the finishing and maximize the flavor.

• Different bean needs to mix with different amount of milk, to eliminate the rest of the bitterness, while maximized flavor and thickness.

• Always try to grind finer with lower pressure, after a recipe is found, it may brings to you a different taste.
  • This also applies to light roasted or much degas-ed bean.
  • By carefully choose a finer grind settings with low and decreasing pressure, it is possible to make an espresso that emphasizes the flavor without lowering the extraction rate.
    • Needs more tests.

The signal of over-extraction signal is bitterness in long lasting aftertaste.

The signal of channeling is sudden/fast increasing flow rate or decreasing pressure.

If puck suddenly loses pressure for no reason, it is probably because CO2 is leaking too much since beans are not consumed in time, just grind half level finer (Niche Duo) and it should be fine again.

It is important to discard some ground right after changing the grind settings, otherwise different sizes of ground will mix together and make channeling happen more easily.

Over-weighted dose could also lead to uneven extraction because the puck expands all the way to the group head, leaving no room to distribute water evenly.

When doing espresso with ice and fresh milk without frothing, bitter will become obvious, adjust to emphasizing acidity.

Light roasted bean

Always starts with 6~1bar/94C and find the finest grind setting, and then perform adjustment.

If bitterness easy to show up, try 9~1bar/96C with 1:1.5 yield.

Strong without Bitterness

To emphasize flavor and increase thickness, try fine grind / low pressure / medium temperature / 1:1.5 yield.

Beans that difficult to extract

Need high pressure and temperature enough to achieve a slow flow rate, only grinding finely may not enough.

Puck Prep (needs experiments)

https://www.youtube.com/watch?v=4dRYw8yl_dg

• Denser puck (or slower flow) increases body, decreases the risk of channeling.
  • Increase the flow rate of pre-infusion.
  • Increase puck weight
  • Decrease the space between the puck and the shower screen (by using smaller basket).
• Looser puck increases characteristic.
• Thicker puck increases body (by using taper basket).

https://www.youtube.com/watch?v=1qyFDbkRrOA

Milk Frothing

• Organic Valley > Darigold
• Costco / Kirkland Signature: smelly
• Good & Gather, Horizon: too sweet
• Maple Hill: too thick
• Lactose Free: too sweet
• Low fat / fat free: not enough fat and protein for frothing

Latte Art

• When pouring on a 6oz cup, frothy milk needs to sitr strong and fast with only a small amount during fusion.

Latte Art Demos