Brewing Espresso: What You Can Control

Coffee type

• Arabica: Lighter, fruity, sweeter, notes of chocolate.

• Robusta: Stronger, more caffeine, robust, full-bodied. Less sweet.

Roast Level

• Light

  • Tends to be more acidic, no bitterness, fruity and less forgiving of technique

• Medium

  • Tends to be more balanced with bitter and acid

• Dark

  • Tends to be more bitter, low acid, and more forgiving of technique

Age of Beans and Resting

• Fresher beans produce more crema

  • More CO2 is still trapped from roasting process

• Resting beans allows CO2 levels to decrease, which can disrupt extraction process

• Rest beans before use (espresso)

  • Dark roast: 3-10 days from roast date

  • Medium: 10-21 days from roast date

  • Light: 3+ weeks from roast date

Grind

• Grind needed will change with age of beans, temperature, humidity, etc

  • Will not always be the same for your preferred formula

• Use 2-4 spritzes of water on beans prior to grinding to help decrease static electricity

• Use a burr grinder for finer and more uniform grounds

  • Conical or Flat burr

  • Slow feed into the grinder with it already started

    • When you have too many beans trying to get through this causes a jam, and the beans rub against one another increasing static electricity and heat.

    • If you start the grinder from full stop with beans already on the burrs, you grind the first few beans at a low RPM and this increases fines and impacts the grind consistency

Water

• Soft to medium filtered water with balanced minerals

• The type of water used can greatly impact the flavor of the resulting espresso

  • Hard water tends to neutralize acidity in specialty coffees due to bicarbonate, and this can make the coffee taste flat

Temperature

• Use different temperatures depending on roast level

  • Dark: 82-86 degrees Celsius

  • Medium: 86-93 degrees Celsius

  • Light: 93-97 degrees Celsius

• Pre-heat portafilter and espresso cup

  • Run a single shot into the empty portafilter, then pull out and pour the water into the espresso cup

  • This heats up the portafilter, cup, and helps water to keep temperature consistent throughout the process

  • Also reduces heat loss due to portafilter and cup being heated up and not siphoning heat off

Brew Ratio

• This is ratio of grounds weight to shot output weight in grams

  • 18grams of coffee with 36 grams water (1:2)

  • For dark start at 1:1-1:1.5, for medium 1:2 – 1:2.5, for light 1:2.5 – 1:3.5

    • Explore from here based on your taste preferences

    • Aim to pull the shot in 25-30 seconds at first

Pull Time

• Adjust brew time by adjusting dose and grind level

• Always use pre-infusion or blooming by soaking puck for 5-30 seconds

  • This helps evenly distribute water through puck and decreases channeling

Extra Tips

• If you can use a bigger basket you can use a larger dose, and this allows you to grind coarser.

  • This decreases chances of channeling, gives a better extraction, and decreases coffee particles that get in drink which will increase the bitterness

• Coffee has 3 phases when brewing: (1)Sour/Salty, (2)Sweet, (3)Bitter

  • Use this to identify if you need to increase/decrease extraction, change your ratio, or change your grind

• Try a blooming shot

  • Pre-infuse at a low pressure and then stop pump for about 30 seconds

  • This soaks the entire puck and can improve complexity of the shot and improve extraction