The density of ground vs. unground coffee

23 02 2010

Does ground coffee take up more, less, or the same volume as whole bean coffee? If I want two scoops of ground coffee, how many scoops of whole beans should I put in the grinder?

To find out, I put two scoops* of coffee beans in my blade grinder and ground it fine. After putting it into a plastic container, I gently shook it to get the coffee to settle, as it would in a package of ground coffee.

The result: pretty darn close to the same volume.

Two scoops (16 grams) of coffee, whole and ground

* The scoop I used is from an Aeropress, and is somewhat larger than a typical coffee scoop. According to a scale, two scoops of coffee is just under 16 grams.


Eggs and air bubbles

22 02 2010

This morning I put some eggs in a pot of warm water and I noticed a faint whistling sound, as though from the worlds tiniest teakettle. When I looked in the pot, I saw tiny streams of bubbles coming from some of the eggs:

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Re-roasting coffee beans

20 02 2010

My brother recently sent me some coffee (Kenya Peaberry¬†Thika Gethumbwini) that was supposed to be really good. For what it’s worth, it had a rating of 96 on I can’t vouch for the validity of those ratings, but surely the rating must mean something. Unfortunately, it turned out to be very sour, no matter what I did with the temperature and brewing time.

I’m not an expert in coffee flavors, but it also tasted kind of “planty” or “green” to me. From what I can find on the internet, this combination of factors suggests that the berries were possibly underripe when picked, and that perhaps they should have been roasted darker. I almost threw out the coffee, but then I had the bright idea of re-roasting them.

Supposedly the beans should get up to about 450-475 degrees inside, so I heated my cast iron dutch oven up to 500 degrees on the stove (an infrared thermometer was really handy here) and tossed in some beans. Then I turned the heat way down, covered, and stirred occasionally. I kept checking the temperature to make sure it didn’t get too hot. The beans occasionally crackled and jumped a little, and a bit of smoke came out every time I opened the lid. It smelled a little like burnt popcorn. The beans were on the stove for maybe 5-7 minutes, and at the end, I poured them into a collander and shook them around to cool. Here’s a shot of some beans before and after:

Coffee before and after second roasting

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Visualizing my net worth

19 02 2010

Today I decided to see my how my net worth would look next to Bill Gates’s net worth. According to Wikipedia, he has about 50 billion dollars, and made a rough guess that I had about 25 thousand (including savings and assets). According to these numbers, he has two million times as much money as I do.

In terms of distance, if his money was 100 meters, then mine would be 1/20th of a millimeter, or 50 microns. I measured a hair from the top of my head at 65 microns. Imagine that Bill Gates’s earthly possessions are the length of a soccer field, and then put a hair across that length. The width of that hair would represent more than everything I own.

This micrometer measures in inches (.05mm is just under .002"), and can open to a maximum of 1". The barely-visible gap represents my life savings.

This hair measures about .0025", which is about .065 mm (65 microns).