Open DB of Coffee grind distributions

This is a repo for sharing data generated by https://github.com/jgagneastro 's coffeegrindsize application.

Background

Coffee particle distribution is important to get a good pourover, but depending on the grinder and the bean, the distributions may vary significantly. Up until now, there has been no public effort to collaborate on gathering this data - a problem this project aims to solve.

Aggregated data as of 2021-01-26:

Grinder	# of Samples	Grind Quality	Efficiency	Diameter + Scatter
LingLong Ace R1	1	1.33	81.2%	1.24 +/- 0.51 mm
Timemore C2	1	1.06	79.7%	1.25 +/- 0.58 mm

Prerequisites to submit your data

You will need:

• a coffee grinder
• a few (ideally speciality grade) coffee beans
• a camera (8+ megapixels)
• a PC or Mac to run the analysis software
• a bit of your time and effort

Before starting, make sure you have the above and can run the software. If you're on a Mac, you can download directly from https://github.com/jgagneastro/coffeegrindsize (code -> download zip) and run App/dist/coffeegrindsize.app If you're on a PC, you can download the fork with an exe build made by github.com/dssch here: https://github.com/dssch/coffeegrindsize/blob/master/coffeegrindsize.exe for now until it gets merged into jgagneastro's main repo

Instructions

• Get a sheet of white A4 (210 x 297 mm) or standard US letter sized paper (8.5 x 11 in). If using a manual or single dosing electric grinder, put in a single bean and grind at a pourover medium-fine setting onto the paper, moving the paper or grinder to distribute the grinds evenly across the paper. If using a non single-dosing machine, do your best to output as little coffee onto the paper as possible. If there's any grinds stuck on your grinder, gently brush them onto the paper as well. Gently use a fork or chopstick to move around any clusters of grinds stuck together. Your paper should look something like: https://i.imgur.com/A1C2RPA.jpg

• Take a photo with a camera or phone with at least 8 megapixels, with good lighting, no shadows, as perpendicular to the paper as possible, and showing as much of the entire paper on frame as possible. Do this carefully as your submission cannot be accepted if it does not meet these requirements.

• Copy this photo to your computer and open the coffeegrindsize app.

  • Click [Open image] (Use .jpg instead of .png if on Windows).

  • Click [Select Reference Object] and select the distance from two opposite, diagonal corners of your paper.

  • Input the [Reference Physical Size]: If using A4 paper, input [364] mm. If using US Letter paper, input [353] mm.

  • Click [Select Analysis Region] and select just inside the corners of your paper. Press [Esc] when you have encompassed all your grinds within the paper.

  • Click [Threshold Image] and wait.

  • Click [Launch Particle Detection] and wait.

  • Optionally, If you see any clumps of grinds detected, use [Erase Clusters] to omit that part of the image, or retake your photo.

  • Click [Create Histogram] to see your data as an image. The [Average Diameter] reading should be around 1.25 mm so that everyone's submissions can be compared directly. If your reading is not between 1.20 and 1.30 mm, please adjust your grind size and retry. Thanks for your patience and understanding.

  • Click [Save Data] to save your data to your computer. Give it a unique name in the format [YYYYMMDDHHMMSS_yourusername].csv

  • Upload your raw image to imgur.com, to be used for validating that your raw image follows the above guidelines

  • Fork this repo, and create a pull request with a new folder with the structure:

  • data

    • YYYYMMDDHHMMSS_yourusername
      • README.md (copied from TEMPLATE.md and fill out the details as best as possible)
      • YYYYMMDDHHMMSS_yourusername.csv (from the app)
      • YYYYMMDDHHMMSS_yourusername_stats.csv (from the app)

• Enjoy a cup of coffee after your hard work!

Helping out this project

If you have any ideas for improvement, or are a programming/data/coffee expert and would like to join the admin team, please submit a Github issue! If you know anyone who would be interested in participating, share this project with them!

Ideas for improvement

• Easier way for users to submit their data (submission form that automatically creates a Pull Request)
• Automatically updated visualizations of all the data, comparing across grinders, beans, etc.
• Compile list of appropriate grind sizes for popular grinders to get near targeted 1.25mm diameter
• Community or forum for discussion

Disclaimer

I do not work in the coffee industry and have no vested interest in the results of this data, and am only providing this as a way for the community to share their results in one place. Anyone who submits any data to this repository implicitly acknowledges that they have no vested interest in the grinder they are submitting the data for.

Special Thanks

• Jonathan Gagne for writing the coffeegrindsize app
• dssch for packaging a Windows version of the app
• All contributors who added their data