tags: [] - coffee/brewing/espresso - coffee/equipment aliases: - Coffee dosing - Espresso dosing - Dose weight

Dosing¶

Tags: #coffee/brewing/espresso #coffee/equipment Aliases: Coffee dosing, Espresso dosing, Dose weight Related: Espresso MOC | Puck Preparation | Distribution Techniques | Tamping Status: ✅ Complete

Overview¶

Dosing is the process of measuring and delivering a precise weight of ground coffee into the espresso basket. It is the first critical step in puck preparation and one of the most important variables affecting espresso extraction quality and consistency. In espresso, the dose refers to the dry weight of ground coffee placed in the portafilter basket, typically measured in grams. Common doses for standard double baskets range from 15–22 g depending on basket size, coffee characteristics, and the desired recipe.

The Dose in Espresso¶

The dose is one component of the classic espresso recipe ratio:

Dose : Yield : Time

For example: 18 g in, 36 g out, 28 seconds represents a 1:2 ratio extracted in 28 seconds. Even small dose variations (±0.5 g) can significantly impact extraction, affecting puck depth and resistance, extraction time and flow rate, and strength and concentration. Without consistent dosing it is not possible to accurately evaluate grind settings or other variables.

Why Dosing Matters¶

Consistency¶

Dose directly affects:

Flow rate — More coffee creates more resistance, slowing extraction. Less coffee allows faster flow.
Headspace — The gap between puck surface and shower screen affects water distribution and pre-infusion behaviour.
Contact time — Deeper puck beds increase water contact time with coffee.
Strength — For the same yield, higher doses produce stronger, more concentrated espresso.

Basket Compatibility¶

Each basket has an optimal dose range:

Under-dosing creates excessive headspace, poor water distribution, and weak puck structure
Over-dosing leaves insufficient headspace, may cause the puck to contact the shower screen, and creates uneven compression

Dosing Methods¶

Grind-by-Weight¶

The most accurate method. The portafilter (with dosing funnel if used) is placed on a scale, tared to zero, and coffee is ground directly into the basket until the target weight is reached.

Advantages: Most accurate and consistent; immediate feedback; no wasted coffee; essential for single-dosing workflow.

Requirements: Accurate scale (0.1 g precision); compatible grinder setup; dosing funnel to minimise mess.

Timed Dosing¶

The grinder is programmed to dispense for a specific duration. The dose weight is verified periodically and the timer adjusted as needed.

Advantages: Fast and convenient; hands-free; well-suited to commercial workflow.

Disadvantages: Requires frequent calibration; affected by grind size changes; bean density variation affects dose; grinder retention causes inconsistency.

Volumetric Dosing¶

Coffee is filled to a mark or chamber and then transferred to the basket.

Advantages: Simple; no equipment required.

Disadvantages: Very inaccurate; affected by grind size, bean density, and settling; not recommended for quality espresso.

Manual Weighing¶

Coffee is ground into a separate container, weighed, and then poured into the basket.

Advantages: Accurate; allows pre-weighing multiple doses.

Disadvantages: Extra handling step; increased static transfer issues; more cleanup required.

Choosing the Dose¶

Basket Capacity¶

The basket manufacturer's recommended range is the starting point:

Basket size	Typical dose range
14 g basket	12–16 g
18 g basket	16–20 g
20 g+ basket	18–22 g+

VST and IMS precision baskets have specific dose recommendations.

Coffee Characteristics¶

Light roasts — Often benefit from higher doses (19–22 g); denser beans require more mass for adequate extraction
Dark roasts — Often work better with lower doses (15–18 g); more porous beans expand more when wet
High-altitude beans — Denser; higher doses may be appropriate
Lower-altitude beans — Softer cell structure; moderate doses

Recipe Intent¶

Recipe style	Typical dose	Ratio
Ristretto	20–22 g	1:1.5 to 1:2
Normale	18–20 g	1:2 to 1:2.5
Lungo	16–18 g	1:2.5 to 1:3+

The Dosing Workflow¶

Single-Dosing¶

Whole beans are weighed for one dose, ground directly into the portafilter on a scale, the weight is verified, and puck preparation continues. This approach maximises freshness and allows easy switching between coffees.

Hopper-Based Dosing¶

The grinder hopper is loaded with beans and timed or manual dosing is used. Dose weight is verified periodically. This is the standard commercial workflow but requires regular calibration as bean density changes with age and humidity.

Dosing Precision and Tolerance¶

Context	Target tolerance
Specialty café	±0.3 g
Home / enthusiast	±0.5 g
Commercial acceptable	±0.8 g

Tighter tolerance improves shot-to-shot consistency, the ability to dial in accurately, and the reliability of troubleshooting.

Common Dosing Problems¶

Inconsistent Doses¶

Causes: Grinder retention variations; scale drift or inaccuracy; static causing grounds loss; operator inconsistency.

Solutions: Single-dose grinding; accurate scale; RDT (Ross Droplet Technique) to reduce static; standardised technique.

Under-Dosing¶

Symptoms: Very fast shots (under 20 seconds); thin, weak body; excessive headspace; puck does not form a cohesive disc; channelling.

Solutions: Increase dose to the basket's recommended range; consider a smaller basket if the current basket is too large.

Over-Dosing¶

Symptoms: Puck contacts the shower screen after brewing; screen imprint on top of puck; very slow or choked shots; uneven extraction.

Solutions: Reduce dose to the appropriate range; use a larger basket; check basket and portafilter fit.

Static and Retention¶

Symptoms: Grounds stick to grinder, container, or funnel; inconsistent doses despite timed grinding.

Solutions: RDT (mist beans lightly before grinding); single-dose workflow; bellows or blower to clear retention.

Dosing Tools and Equipment¶

Essential¶

Precision scale — 0.1 g accuracy minimum; fast refresh rate; auto-off disable function
Dosing funnel — Fits portafilter basket; allows overfilling without mess; magnetic attachment preferred

Optional¶

Dosing cup — For single-dose workflow; allows pre-weighing beans
Bellows — Clears retention from grinder; improves dose consistency

Advanced Dosing Concepts¶

Grinder Retention¶

Coffee grounds remaining in the grinder between doses mix with subsequent grinds. The first shot after changing a grind setting may receive a mixture of old and new coffee. Solutions include single-dose grinders with minimal retention, purge doses after changes, and factoring retention into the pre-weighed bean weight.

Dose Freshness¶

Fresh-ground coffee has higher CO₂ content, which affects puck preparation behaviour. Grounds should always be used immediately after grinding; flavour degrades within minutes once ground.

Seasonal Adjustments¶

Bean characteristics change with crop age, humidity, and temperature. Dose targets may require adjustment when switching to new crop lots or as ambient conditions change significantly.

Dosing and Recipe Development¶

The Dose-Ratio Relationship¶

Example	Ratio	Effect
18 g → 36 g	1:2	Standard strength
20 g → 40 g	1:2	Same concentration, more volume
18 g → 27 g	1:1.5	Higher strength; ristretto style

Finding the Optimal Dose¶

Start with the basket manufacturer's recommendation (usually 18–20 g for a double)
Test the range (±2 g from the starting point)
Maintain ratio and time while varying dose
Taste systematically — assess clarity, balance, body, and finish
Evaluate consistency — identify which dose is most forgiving

Key Facts¶

Accurate dosing is foundational to espresso consistency: dose affects extraction yield, time, flavour intensity, and brew ratio
Specialty coffee precision target: ±0.3 g; competition standard: ±0.1 g
Standard double dose: 16–20 g (most commonly 18 g); standard ratio 1:2 (18 g in, 36 g out)
Grind-by-weight is the most accurate dosing method; timed dosing requires regular recalibration
Static electricity and grinder retention are the most common causes of dose inconsistency
Dose should always be measured by weight, not by volume; volumetric dosing is unreliable

Espresso MOC
Puck Preparation
Distribution Techniques
Tamping
../../../Maps of Content/Grind Size MOC
Extraction Ratio
Coffee Scales
Dosing Accuracy

References¶

Changelog¶

Date

Change

2026-05-02

Compliance review: fixed frontmatter (inline → block YAML; tags corrected to coffee/*); added metadata block; added ## Overview heading; fixed ../ and 05_PUBLISHING/... wikilinks; removed Dosing Checklist (second-person checkbox list); removed snarky editorial comment in Volumetric Dosing; converted "your" references to third-person; removed promotional closing line; added Key Facts, References, Changelog, copyright

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