In this post I discuss the effects of coffee varieties, origin and processing on average extraction yield and brew time.
Author Archives: jgagneastro
The Physics of Kettle Streams
In this post, I discuss the physics of kettle stream and how we can maximize extraction evenness by changing pour rate and height.
Why Can’t we Grind Coffee Finer for Pour Over ?
In this post, I discuss issues and possible avenues for grinding finer for filter coffee
Measuring Brew Water Properties
This post describes some available tools for measuring water properties relevant to coffee and presents ways and a web tool to hack aquarium kits for a better precision.
The Physics of Fines Migration
In this post, I explore the details of physical phenomena that can cause fines to migrate and clog coffee filters.
The Struggle for a Steady Kettle Flow
In this post I discuss recent developments in my efforts to stabilize my kettle flow rate.
Sprudgie Awards Nomination
This is a short post just to let you know that my blog Coffee Ad Astra was nominated for a 2019 Sprudgie Award for best coffee writing ! I am super excited about it ! 😊 An online voting poll was just started by Sprudge to determine the winner, any help either from voting or spreading theContinue reading “Sprudgie Awards Nomination”
The Hardness of Green Coffee
In this post, I show that surface hardness might vary more than mass density across different green coffees.
What is Astringency ?
In this post I describe what causes astringency, and talk about ideas how we could potentially measure it or remove it post brewing.
What Affects Brew Time
In this post I discuss the variables that affect brew time in detail
