Grind Quality and the Popcorning Effect

I often heard worries in the coffee community about a difference of quality in the coffee grind size distribution when grinding with a full hopper versus a single dose of coffee in an otherwise empty hopper. The idea behind this is that coffee beans forced through the rotating grinder burrs have no choice but toContinue reading “Grind Quality and the Popcorning Effect”

An App to Measure your Coffee Grind Size Distribution

[Edit April 25 2019: Please note this is not an iPhone or Android app, and I have no plans to release it as such. You can use your phone or any other camera to take pictures of your ground coffee, but then you need to install the application on either OS X or through PythonContinue reading “An App to Measure your Coffee Grind Size Distribution”

Some Strategies to Keep your Coffee Fresh

[Edit October 28 2019: I now strongly recommend against using oxy-sorbs or any oxygen scavenger bags with coffee. I will eventually write a detailed post about this, but it can impart a really bad taste to coffee; for now you can find more information here.] There are few things more annoying than discovering some ofContinue reading “Some Strategies to Keep your Coffee Fresh”

A Recipe to Brew High Extraction Coffee with the Siphon

Today I am finally sharing a recipe for the siphon brewer. I will use a bit of technical jargon at times in this blog post. If you encounter a word you’re not familiar with, I recommend you consult Mitch Hale’s glossary. The siphon method is far from being appropriate for most people’s daily routines, asContinue reading “A Recipe to Brew High Extraction Coffee with the Siphon”

Testing a Model of Extraction Dynamics

In a recent post, I presented a mathematical model for the dynamics of coffee extraction that is based on a few simple hypotheses. One of these is that the rate of extraction decreases exponentially. The rate at which it decreases can depend on many things: the type of coffee, the roast, the amount of agitationContinue reading “Testing a Model of Extraction Dynamics”

A More Accurate Way to Calculate Average Extraction Yield

I recently wrote about the detailed explanations and calculations behind the equations we use to estimate average extraction yield from coffee concentration (often called TDS) measured with refractometers. If you have not seen this discussion, I highly recommend reading it before you start reading this blog post, as it introduces a lot of the conceptsContinue reading “A More Accurate Way to Calculate Average Extraction Yield”

Measuring and Reporting Extraction Yield

Since I received the VST Coffee Lab III refractometer thanks to Vince Fedele’s generosity, I started logging the concentration (in % TDS) of every coffee I brew. This allows you to calculate the average extraction yield of your brew, which represents the fraction of your coffee beans by mass that was dissolved in your brewContinue reading “Measuring and Reporting Extraction Yield”