Understanding an espresso machine’s anatomy is essential for any barista. Whether you’re pulling shots, steaming milk, or troubleshooting a problem, knowing how each part functions ensures better coffee and safer operation.
- Group Head
- The component where the portafilter locks in and water is dispersed over the coffee puck.
- It includes a screen and gasket and is usually made of brass or stainless steel to retain heat.
- Consistent temperature here ensures consistent extraction.
- Portafilter
- A handle with a filter basket that holds ground coffee.
- Comes in spouted, bottomless (naked), and pressurized variants.
- Must be evenly filled and tamped for optimal extraction.
- Filter Basket
- The metal insert inside the portafilter that holds the coffee grounds.
- Sizes vary (single, double, triple), and hole precision affects flow rate.
- Needs to be cleaned regularly to avoid flavor contamination.
- Boiler
- The machine’s internal tank that heats and stores water for brewing or steaming.
- Single boiler, dual boiler, and heat exchanger types exist.
- Pressure and temperature stability here are key for quality shots and milk texturing.
- Pump
- Responsible for delivering water to the group head at high pressure (~9 bars).
- Most machines use rotary or vibratory pumps.
- A stable pump ensures consistent flow and extraction.
- Steam Wand
- The nozzle used to froth or steam milk.
- Has one or multiple holes (tips) that control steam pressure and direction.
- Must be cleaned immediately after each use to prevent milk buildup.
- Pressure Gauge
- Displays boiler and/or pump pressure.
- Useful for diagnosing performance issues.
- Helps baristas track consistency during extraction.
- Drip Tray
- Collects waste water and spilled coffee.
- Should be emptied and rinsed regularly to maintain hygiene.
- May include a drain pipe in plumbed-in machines.
- Hot Water Tap
- Provides hot water for Americanos or tea.
- Connected to the boiler system.
- Useful but can introduce temperature instability if overused.
- Control Panel / Buttons
- Manual machines use switches or levers.
- Semi-automatics and automatics use programmable buttons for shot volume and other functions.
- Some modern machines include touchscreens and PID temperature controls.\
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Barista Terminology | Episode 10: Advanced Concepts
Barista Terminology | Episode 9: Sensory Evaluation
Barista Terminology | Episode 8: Customer Service Language in the Café
Barista Terminology | Episode 7: Water & Temperature Control
Barista Terminology | Episode 6: Grind & Extraction Variables
Barista Terminology | Episode 5: Milk Texturing & Latte Art
Barista Terminology | Episode 4: Brew Methods Explained
Barista Terminology | Episode 1: The Coffee Bean – From Seed to Roast
Barista Terminology | Episode 2: Barista Tools & Equipment
Barista Terminology | Episode 3: Espresso Basics
