Saturday, November 19, 2022

BH Unlimited Update - Nov 19th 2022

The Espresso Vanishes: Part 2

BH Unlimited Update, Nov 19th 2022.

In the last update, we presented the first instalment of The Espresso Vanishes by Sebastien Delprat. It's a four parter, focussed on finding out who really invented the first espresso machine. This week, BH Unlimited subscribers can get stuck into Part 2, entitled Back to the Roots. If you don't have a subscription yet, that's okay, Part 1 is open-access and we're keeping Part 2 free to read across the weekend.

This week, Sebastien starts hunting for the precursors to Moriondo and Bezerra. Two starring roles go to Giraud and Romershausen. Both released patents in 1847 for machines with external coffee holders — call them proto portafilters. Giraud's machine has a similar stature to Moriondo's designs from 37 years later.

Inventions from Giraud (left) and Römershausen (right), both from 1847

Romershausen was on a very different tip, where the user had to turn the top half of the contraption upside down, once the water was boiling. This allowed the water to be pushed through the coffee bed under a slight positive pressure. It's a similar principle used by the Steepshot brewer, from nearly 170 years later. Though, judging by the illustrations from his patent (above), flipping over the Romershausen brewer looks like a much more dangerous feat than inverting an Aeropress.

Sebastien Delprat is an astoundingly thorough researcher and we think you will enjoy reading part two from this series. If you want to check Sebastien's own superb blog, just head here.

Roasting Science

In our Roasting Science course this week, we launch a new chapter about the physics of heat transfer. Heat transfer governs so many concepts in roasting — creating roast profiles for different beans; ensuring beans are fully developed; and even many roast defects. Roasting is, after all, just the process of transferring heat into coffee beans.

We begin with some background, explaining in detail the different methods of heat transfer. You might have learned about the differences between conduction, convection, and radiation in high school, but did you know that conduction is also an important part of convection? And did you know that all objects radiate heat, all the time — as long as they are above absolute zero?

An infrared heating element inside the drum of a Rubasse coffee roaster

Understanding these concepts can explain why bean surfaces are more likely to get burned by conduction than by convection, and why convection is so much more efficient at transferring heat than conduction. It can help you understand how to control the relative amount of conduction and convection in your roaster. And it can help you understand the fascinating potential of infra-red and microwave radiation in building roasters that can heat beans from the inside out.

BH Unlimited subscribers have advanced access to each new lesson as the course progresses.

Quick Links

WCR Announces Launch of the Innovea, Global Coffee Breeding Network.
This is big news in the coffee plant breeding world because it's the first global infusion of new breeding materials in over 50 years. The last time this happened was in the late 1960s, when coffee researchers at Centro de Investigação das Ferrugens do Cafeeiro (CIFC) in Portugal developed the Catimor and Sarchimor breeds.

Jeremy Challender: "Barista Hustle is the Netflix of Coffee".
Are you interested in the history of the third wave? Our Dean of Studies, Jem Challender is obsessed with it. He discusses this and a whole lot more in an interview with Simonetta Spissu from Milan-based coffee news outlet, Comunicaffe. You'll learn a lot about the objectives of Barista Hustle and the Aussie coffee culture we came from.

An Ad-Free Learning Experience

At BH we never do ads for other company's products on our website. There's no product placement in any of our courses, newsletters or blog posts. Our only income comes from what you pay for your subscriptions. When you see machinery or coffee gear mentioned in any of our educational material, or featured in our course videos, we have chosen to use that equipment because we like using it, because we think it's historically significant in the evolution of the espresso machine, or because it shows you something you need to see about modern coffee culture. It's as simple as that.