Roasting coffee at home: a DIY coffee bean cooler

Coffee Cooler - 03   Coffee Cooler - 01Coffee Cooler - 18   Coffee Cooler - 09

I never really set out with the goal of roasting my own coffee beans, it just kind of happened.

It started a month ago when we got a coffee grinder. Naturally we started getting whole bean coffee, which we used at a rate of about one pound per week. While I’m not (by any standards) a coffee connoisseur, I found myself noticing that the first pot of coffee out of the new can really was just betterthan the last pot of coffee out of the old can– meaning that the coffee quality does actually decline noticeably after just a week.

Now, that’s a minor annoyance, and hardly cause for action. But, two weekends ago I happened to be browsing in a home brewing store (needed champagne yeast– that’s another story) where there were sealed bags of green coffee beans just sitting there on the shelf. Fair trade, organic, and in a number of varieites. Only 5 bucks a pound. So what the heck, right?

It turns out that there’s a common and cheap method of roasting coffee at home: using a regular air popcorn maker. You put the beans in the popper as though they were popcorn kernels, heat them for a few minutes until they’re properly roasted, and then cool them. (You can read the details of this process here, here, here, and here, amongst other places.) This is kind of neat because it doesn’t take much in the way of equipment and it roasts just enough for a big pot of coffee.

The weak point in the popper method is the cooling. The beans keep roasting as long as they are still hot, so many of the sites suggest pouring the beans back and forth between a couple of metal colanders until they cool down. We tried it, and while it did cool them faster than a cookie sheet, it was more tedious than fun. It also seemed a bit silly to use this nice semi-automatic roaster and then turn it over to a manual process for the next few minutes. So, here is our better (if somewhat obvious) solution: a dedicated coffee cooling tower, built from a second modified air popper. Continue reading

Marmalade is way easier than it looks

Marmalade 01

 

While trying to figure out what to do with about 75 pounds of fruit that our citrus trees bestowed upon us in January, we came across an interesting fact: marmalade is really easy to make. People of older generations may know this already, but so far as we knew, marmalade was one of those mysterious things that strictly comes from a jar. It turns out that all you need is citrus fruit, water, sugar and some time on the stovetop.

 
Continue reading

Everyday science: Litmus candy

Kitchen Science 01   Kitchen Science 34

We picked up some of these blueberry/yogurt candies at Trader Joe’s, which didn’t really merit a mention until we looked at the ingredients list:

Ingredients

Well, now, that is interesting. The last ingredient in the list is red cabbage extract, “for color.” But… red cabbage is one of those pH-indicating substances (Link 1, Link 2), that happens to make a pretty good DIY version of litmus paper.

So… if these candies have red cabbage extract for color, do we really have litmus candy?
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Precision in packaging

Szechuan peppercorns


Sichuan peppercorns, oh yeah! Raven of Made with Molecules after eating them wrote, “There’s a war in my mouth.” They create a riot of numbing and tingling sensations, particularly if you can get relatively fresh ones (i.e. not stale from sitting around in a Whole Foods bulk bin). Raven links to an abstract about the particular anesthetic-sensitive potassium channels inhibited by hydroxy-alpha-sanshool, one of the components of sichuan peppercorns that make them so exciting.


Science aside, we recently found some in a local asian grocery store, and were particularly struck by the packaging. American packaging often has annoying disclaimers about how contents are packed by weight and may have settled. These peppercorns were not only weighed, but the precision of the scale is indicated! If only all packaging was so straightforward. I was going to complain that the package doesn’t say what kind of peppercorns were inside (sichuan peppercorns are not related to other peppercorns) but then realized that the Chinese characters are specific to these “flower peppers” even if the English words are more general. In any case, the reddish husks are recognizable through the bag.

Evil Mad Scientist Laboratories: Year 3

Evil Meggies

Happy birthday to us! Evil Mad Scientist Laboratories is now three years old.

To celebrate, we’re rounding up our most interesting projects from this past year.

Quick projects and observations:

Magnet tricks
17 cool magnet tricks

moneyDensity.kopi
The monetary density of things

Cheap calendar 2
Cheap Perpetual Calendar

Parts Tray-14
Contact Lens Case Small Parts Tray

Simple LED Projects:

lanterns - 11
Quick, easy, temporary, and beautiful LED garden lights

RoboGames Awards (on)
RoboGames Awards

LED Ghostie
LED Ghosties for Halloween

Food Hacking:

Dry Ice Martini
The Hungry Scientist Handbook

Decoder 2
South Indian Restaurant Menu Decoder

 

"That's no melon!"
“That’s no melon!”

Grillin 2
Hot Dog Bun Grilling Jig

LOLHearts - 34
Improved Custom Message Hearts

Apple Pie
Now that’s an Apple Pie!

Caprese - 16
Eyeball Caprese

Fractal Snowflake Cupcakes - 24
Fractal Snowflake Cupcakes

 

CandyFab

CF6k
The CandyFab 6000

Papercraft

Harley Sleeps
Cardboard Cat Chaise

EdgeLitCard - 49
Edge-Lit Holiday Cards

Hex Boxes5
Hexagonal Stacking Boxes

frabjous - 01
Making a Frabjous

Electronics Projects

Interactive LED Dining table
Interactive LED Dining Table Circuit

 

Color distortion
Giant seven segment displays

DarkPumpkin - 11
Dark detecting jack-o’-lantern

SolarCircuits - 06
Simple Solar Circuits

Soft Circuit Merit Badge14
Soft Circuit Merit Badge

Kit Projects

Meggy Rainbow
Meggy Jr RGB

VideoPeggy - 09
Video Peggy in action

Peggy 2 RGB
Peggy 2 RGB

2313Card - 1
ATtiny2313 breakout boards

Card1.1Top
Revised ATmegaXX8 boards

Crafty Projects

d12 Bag
DIY d12 Handbag (of Holding)

Meggy Jr RGB Cozy-21
Meggy Cozy

no-sew iPhone cozy14
No-sew iPhone Cozy

fabric klein bottle
Fabric Klein Bottle

Seat recovery
Reupholstery with Used Denim

Missile Command Skirt 24
Missile Command Circle Skirt

Fishbowl cat quilt29
Fishbowl Cat Quilt

Maulie-25
Turning Mollie into Maulie

Bicycle lunch bag
Bicycle Frame Lunch Bag

Acrylic Nesting Bracelets-1
Sinusoidal Bracelet Design

Microcontroller Projects

Time exposure
Tennis for Two, a video game from 1958

stockpumpkin - 11
Scariest Jack-o’-Lantern of 2008

mignonette - 09
70 bits of gaming goodness

Serial Port Added
AVR Serial Communication

lissajous-dark - 07
POV Lissajous figures

Mobius Circuit - 21
Single sided circuit board

bulbdial_1
A Bulbdial Clock

Geek Design

Snowflake generator
Vector Snowflake Application

Kindling
The Amazon Kindling

Pi (squared) trivet - 9
Pi Pie Trivet

lego - 2
Lego Kitchen Crafts

Binary Birthday
Binary Birthday

(Whew!)

Stickers for the Organic Gardener

Organic Gardening Stickers


The influence of the Slow Food movement is increasing, and gardening is getting ever more popular. Even the tech bloggers are posting about local pollinators and getting beehives. In this environment, it is fitting that a new use has been found for our Now Slower and with More Bugs stickers, which were first seen in the wild back in December 2007. If you find a good use for them, we’d love to see pictures in the flickr auxiliary!


(Thanks, Lorien!)





Organic Gardening Stickers


Photos by Lorien Tersey