Vacuum Press

 A Coffee Maven Brew-At-Home Moment

This semester I was pleased to be able to conclude our Secret Life of Coffee Honors Seminar by hosting class at Cloverfield, a.k.a. Casa Hayes-Boh, a.k.a. our house very close to campus at 41º75’07” N 70º58’31” W. 

This allowed us to share old-house stories, Latin American art, and most especially a few coffee tricks that are a bit difficult to try at school. Having been thwarted in various, nearly successful efforts to install a roaster on campus, I roast most of the coffee for this class -- and all of my classes -- in a 1-pound countertop Behmor drum roaster. 

Before demonstrating that process, however, I dusted off my vacuum press. It is a crazy-looking contraption, slightly scary to use. But it makes remarkably smooth coffee. Here is a Bodum company demo -- note the preparer's fearless use of long-sleeved, white clothing. I use my vacuum pot so infrequently that I reviewed this video before the students arrived.

They had seen a similar pot in use -- improperly -- in the inadvertently hilarious 1961 video This is Coffee, in which the coffee boils vigorously and dangerously for far too long and is stirred with a metal spoon. 

Those who have seen the Coffee Maven in his natural habitat will not be surprised that I neither measured nor stirred the coffee yesterday. Usually I do stir with a wooden chopstick though, as I did both times that I used the pot today.  

Thankfully, one of my students took a couple of candid videos of my efforts yesterday -- these are not scripted as instructional, but you can notice a couple details here that you might not see in the Bodum video.

Part 1 (video by Anna Dykhof):

Part 2 (video by Anna Dykhof):  

My main motivation for creating this blog post was to share some photos I made during the visit, because of another omission during the brewing process. I forgot to show the students what the filter in this device looks like. In fact, it does not look like a filter at all. I am amazed that it works and even more amazed that someone even thought of this as an option. It is a little bit difficult to describe, but these three photos provide some idea.

First, the overview. This is a plastic disk at one end of a chain with a small spring at the other end. The idea is that the spring holds the disk snugly against the bottom of the "upstairs" part of the brewing vessel.

A close-up of the disk shows that the bottom has a series of very small grooves:

This disk rests against the smooth neck of the brewer. In this photo, I moved the heavy rubber ring down a bit so that the glass can be discerned:

These grooves allow coffee to be drawn down through the neck of the vessel without bringing any grounds at all with it -- as long as a suitable coarse grind has been selected (as it has). Not only does this work, but it does create a very effective filtration and creates a coffee that is full-bodied and smooth. I made a couple pots worth on the day after our class visit.

Roasting 

And now, the aforementioned roasting. 

We began with 15.9 ounces of green coffee -- right at the capacity of the Behmor and measuring about 2.5 cups by volume. 

I placed the coffee in the Behmor's basket. It could hold a lot more of course, but filling the capacity is only about 20 percent of the volume of the basket, because airflow is key to safe and even roasting.

We roasted for about 18 minutes, which is the default setting for one pound of coffee. At about that time, we got very quiet, so that we could listen for the sound of the coffee cracking as the roast completed and the beans expanded. This is a bit difficult to hear, but an important way to time a roast. One the crack was underway, we switched to the cooling cycle and the coffee continued to tumble in flowing air for another 12 minutes.

The result: 13.5 ounces of coffee (as moisture was driven off during the process) measuring almost 4 cups (as those beans had expanded). The whitish lines on many beans are sugars that are visible at this roast level.

Roasting/brewing/tasting some fine coffees left us all smiling!

BONUS: Tasting-event photos

Prior to the roasting/brewing demonstration at Casa Hayes-Boh (aka Cloverfield), our penultimate class meeting was a small but impactful variation on the end-of-course tasting event that has been the culminating event in this class since I started offering it in 2007.

I took a couple of photos from a distance. 

Jennifer MacCallum of our Honors Program took better photos up close. Thanks for sharing these, Jen!

Where does coffee come from? A lot of places, including
some that are likely to be surprising. We spent
a lot of the semester talking about differences and
similarities among coffeelands.

Coffee can be brewed in many ways, each with its own
appropriate grind level (coarseness/fineness).

A bit more detail on the grind options.

In this course, we always discuss the various ways that coffee
can be processed before it is exported. This semester's class was 
fascinated by the effect this has on flavor and made that a major
part of their research.

This was a small but motivated group who spent all semester
using geography to learn about coffee and coffee to learn about 
geography. (Not shown: one student whose contribution was
an interactive presentation on a laptop.)