Global Espresso Experiment

About the Experiment

We’re excited to invite you to take part in a global data collection project led by Nucleus Coffee Tools, designed to explore how different espresso distribution methods affect cup quality.

This experiment aims to build a more comprehensive and diverse dataset by involving coffee professionals from around the world—representing the different roast styles and different grinder and espresso machines used in real-world espresso preparation.

By participating, you’ll help us better understand the role of distribution in espresso and contribute to a larger conversation around precision, consistency, and sensory impact.

We look forward to seeing your results and reading your insights. Below provides a general summary. If you take part, all supporting details like scoresheets, protocols and guidance will be provided to simplify the process.

Methodology

Objective
To explore how different coffee distribution methods affect the sensory perception of espresso, using a consistent coffee, dose, grind size, and preparation process—with the only variable being the distribution method prior to tamping.

Overview

Participants will blind-taste espresso shots prepared using identical inputs (same coffee, dose, grind size, brewing temperature, tamping method) with only the distribution method varying between samples. This experiment seeks to determine whether distribution tools influence the sensory attributes of espresso such as balance, flavour, and body.

Key details

• Coffee: A locally roasted, popular espresso roast or commercially available espresso roasted coffee. Single Origin or Blend (selected by the host). The same roast batch will be used throughout the experiment.
• Coffee Quantity: 1kg roasted.
• Coffee Age: Aged appropriately for the Experiment Date chosen to suit the recommended age after roast of that coffee.
• Brew Recipe: Dose, grind size, and yield will be determined according to the roaster’s recommendations. Final adjustments to recipe will be decided by the host Barista in advance to suit their specific equipment.
• Tamping: All samples will be tamped using an auto-levelling tamp device to ensure consistency.
• Temperature: Each shot will be served at a controlled, consistent drinking temperature (40–50°C).
• Equipment: Reliable espresso machine and grinder. The host will record the machine, grinder, brewing temperature, pump pressure, and filter basket used.
• Participants: 1 x Barista and 4 x Tasters
• Time: Approximately 4 hours time (2 hours setup and packdown, plus 2 hours for the experiment) for the Barista and 2 hours of tasting time for the Tasters.

Data collection

All participants will be provided with (i) details such as coffee selection, brew recipe, aging and more; (ii) a list of distribution tools and techniques to use; (iii) a tasting format and Tasting Sheet to guide their extraction, tasting and data recording; and (iv) a Blinding Protocol to ensure randomisation.

Participants

We’re seeking any coffee businesses that prepare espresso – whether they’re roasters, a coffee shop or otherwise – to participate in this experiment, with the aim to collect as much data as possible. Opening up this participation to the public helps the experiment to avoid biases, and to provide a more general overview of results using a range of distribution techniques.

All participating businesses selected for this experiment will receive an NCD and/or NCD Pulse distribution tool to assist with their experimentation and data collection (provided they don’t already own them).