Aeropressin'

Today, I brewed up some of Thursday's Costa Rican with the Aeropress. My technique involves mixing 14g of coffee with 240g of water in the Aeropress, and brewing for a minute and half. Then I turn it over and press into a glass. I checked the result on my refractometer.

I had the grinder set at 25, and ground directly into the Aeropress:

I boil 240g of filtered water, allow it to cool to about 208, and begin pouring into the inverted Aeropress:

 

I stir the slurry vigorously when it's about half full, then pour in the rest:

This can be difficult with freshly roasted coffee, as the bloom is larger. Sometimes I need to add in stages to get all the water to fit. Regardless, I start the 1.5 minute countdown as soon as the water meets the coffee.  As this is a full immersion brew, there is no need for a prewet.

The resulting brew had 1.56% total dissolved solids (24% extraction). WAY too strong and bitter, so I dialed down the grinder.  I decided to try 30, which is a bit finer than I had been using for drip. This resulted in 1.31% TDS and a 20% extraction. Pretty darn good.

It's amazing what a seemingly minor adjustment to the grind size can do.

Roast Disaster

Today I ruined a batch of coffee in the roaster. I tried a different program, and it ended prematurely. I couldn't start it up again, because the roaster has a safety feature which will not allow it to start a new roast while it's still hot. It ended up going just to the verge of first crack. I cancelled the cooling cycle to see if the residual heat might carry it a bit further. I could hear a few of the beans getting to first crack, but not many. 

This was the result:

What a mess. It was supposed to be a nice, wet-processed El Salvadorian Bourbon. Notice that some of the beans still have the silverskin attached.

Since there seemed to be quite a variety in roast level, I decided to try tasting some.  I chose 8 grams of the lighter beans:

and 8 grams of the darker ones:

I roasted up a batch of Costa Rican of similar grade to the El Salvador, to about a City+ level:

And for comparison grabbed some old Starbuck's crappy coffee I had laying around. Being Starbucks, it's a Full City+ / Vienna roast:

The poorly roasted beans are quite different from the beans that have completed first crack. They are small, dense and hard. Like green coffee. It is during the first crack stage that the beans expand to their full size.

I decided to do a cupping with 8g of each and 150ml water. I know that's a small amount, but it was a real pain to separate the first 2 samples, so I just went for 8:

 

Here's what the lightest sample looked like in the cup:

Not very appetizing.  It didn't taste any better. Kinda grassy and doughy. My third sample, even though it was only an hour out of the roaster was the best of the bunch:

Can't wait to taste it tomorrow!