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exponentiation ezine: issue [7.0:self-sufficiency]

[self-sufficiency | food]

Roasting Coffee at Home

Coffee is the world's second most traded commodity; only oil surpasses it. Despite its popularity, quality coffee is uncommon, and relatively expensive where available. As good drugs are preferable to mediocre, coffee addicts will seek the best they can get. However, purchasing pre-packaged beans in a grocery store or coffee shop means that you're paying for packaging, labor, and overhead in addition to the coffee itself. Green beans can be purchased directly from local roasters for 15%-50% less than the retail cost of roasted beans. By roasting your own coffee at home, you'll drink fresher, cheaper, and better tasting coffee (if you learn to roast well, that is). The benefits are many, and the process is dead-simple, but mastery takes patience, practice, and dedication. The only downside is that you'll never be able to drink Nescafe again. Before we can discuss the roasting process, some common coffee terminology needs to be covered.

Coffea Arabica: Usually abbreviated Arabica. One of two economically significant coffee species, Arabica crops provide about 75% of the world's coffee. This species requires a great deal of attention and care, but from it comes all premium/specialty coffees.

Coffea Canephora: Commonly known as Robusta. The other major cultivated species, Robusta is hardier, more disease resistant, and yields more cherries per plant than Arabica. However, the taste of Robusta is often likened to burnt rubber. Robusta beans contain 2-3 times the caffeine of Arabica beans.

Origin Character/Profile: The sensory characteristics represented in a region's coffee. This is affected by climate, soil, altitude, genetics, processing methods, drying methods, etc.

Cherry: The fruit of the coffee plant, wherein the seeds grow.

Green beans: These are the unroasted seeds of the coffee plant. Two grow inside each cherry, with the exception of peaberries.

Peaberry: A mutant seed which grows only one per cherry, instead of the usual two. Peaberries are smaller, denser, and more spherical, which means they roast more evenly than regular beans. A peaberry receives all the nutrients usually allotted to two beans, which means they amplify the coffee's origin character. Peaberries are a great choice for skillet roasting.

Dry or Natural Processing: The oldest method of processing coffee. Ripe cherries are spread out in the sun to dry, before further milling which removes the pulp from the seeds. Traditionally used in regions where sunlight is more abundant than water.

Wet Processing: Ripe cherries are added to sorting tanks and run through a de-pulping mill before soaking for 12-48 hours in fermentation tanks which make further pulp removal easier. Beans are then dried, usually by the sun as with Dry Process. Wet processing requires an immense amount of water, and is more labor-intensive due to the many sorting steps which increase quality. Wet Process coffees tend to be "cleaner," fruitier, and have a more pronounced acidity than Dry Process coffees.

Pop or Crack: Refers to a popping noise which takes place at certain times in the roasting process. At first pop, the bean browns and its sugars begin to caramelize. At second pop, the cell walls are beginning to break down and oil migrates to the surface of the bean.

Chaff: A thin outer skin that separates from the green bean while roasting.

Acidity: In coffee terms, this refers not to PH, but to a brightness, or sparkling clear sensation near the tip of the tongue. Pronounced acidity is an indication of high quality coffee, but not its sole determinant. Acidity increases with the elevation at which the coffee is grown.

Body: The weight, or mouthfeel of the coffee. How thick/heavy is the coffee on your tongue?

Flavor: Both the overall impression, and specific notes/tones that emerge at different points. Flavor can change dramatically as coffee cools. Another indication of quality coffee is its taste at room temperature. If it's still delicious, that's a good sign.

Drop (the roast): To add a pre-weighed charge of green beans to the roaster.

Pull (the roast): To remove roasted beans from the roaster to the cooling tray/device.

Storing Green Beans and Roasted Coffee:

The green bean selection at your local roaster could be overwhelming at first, especially if you are not familiar with origin characteristics of common

coffees. If you're totally lost or just don't know what you like, start with a few choices which represent the archetype of a region.

Guatemalan or Costa Rican coffees will introduce you to the bright, clean, and smooth Central American profile. Expect pronounced acidity, a medium body, complex sugars, and a smooth finish.

South Pacific coffees are the inverse of Central America. Try Sumatra, Papua New Guinea, or Sulawesi (Celebes). These coffees are heavy, dense, and earthy, with a thick body and low acidity. They're great with milk and sugar, dense cakes, and fine tobacco.

Africa offers us a little of everything. Kenya AA has a great dry acidity, deep wine tones and berry flavors, and a medium body. Ethiopian Harar is wine-y and incredibly fruity with a distinct blueberry aroma and flavor and medium-heavy body. Harar is dry-processed, which gives it a more complex, but "dirtier" flavor. Contrast it in this regard with a wet-processed Central American, which is cleaner but simpler. Ethiopian Yirgacheffe is often wet-processed, and has a lemony-citrus acidity, medium body, and delicate floral notes.

Once you've located a local coffee roaster, you can begin stocking green beans. One advantage of home roasting is the ability to keep several types of coffee on hand, as green beans are good for about a year, as opposed to a week or two for roasted coffee. Green coffee needs to breathe; it should be stored in a container that allows moisture to exchange with the air. Green coffee can mold in a sealed jar or plastic bag. Find a storage place whose temperature doesn't fluctuate frequently or rapidly, and don't worry about insects because very few find green coffee palatable. Also, at your roasting shop you can usually get free jute coffee sacks, which are extremely useful and durable. These bags are ideal for storing green beans, and can be taken apart and re-sewn with their own thread, allowing you to make storage sacks in any size.

Roasted coffee does not need to breathe as such, but will release carbon dioxide gas, especially in the first 24 hours after roasting. This gas should be preserved if possible, because it protects the coffee from oxygen, which degrades the oils and volatile organic compounds that are crucial to fresh, delicious coffee. Ideal storage containers include: glass "Mason" jars with sealable lids, vacuum-seal bags with one-way valves, or plastic ware with lids. Glass is easy to clean and won't react with coffee oils, but probably shouldn't be sealed too tightly or it could shatter. Keep roasted beans cool and dry, just like green beans. The flavor of your beans will peak around 2-3 days after roasting; they'll be good before then, but may taste grassy, green, or unpleasantly acidic. A few days of resting will mellow the initial sharpness, especially in very dense, high-grown coffees. Any coffee that will not be consumed within 10-14 days should be sealed and frozen. Roasted coffee will greedily absorb ambient aromas, so keep it out of the refrigerator or it'll taste like mayonnaise and plastic. Stale, but otherwise sound coffee often tastes dull, muted, flat, and distinctly of cardboard. Coffee is great fertilizer and has a carbon-nitrogen ratio of 20-1, so save spent grounds or stale beans for your compost.

Roasting overview:

The roasting process is the same regardless of the method employed to that end. The beans must be heated, kept in motion so as not to burn, and rapidly cooled when the desired roast level is attained. During this process, complex and only partially-understood chemical changes take place, which are responsible for transforming bitter, grassy, green beans into delicate, balanced, and addictive roasted coffee.

Coffee roasting is a highly sensory experience, and you'll rely heavily on your sense of sight, smell, and intuition about the roast. Take in as much sensory information as you can. This can be overwhelming and confusing at first, but the more you taste, touch, smell, and listen, the faster everything will "click" in your head. Every type of bean has a different personality and will behave a little differently in the roaster; when you learn what each bean "likes," your roasts will manifest more favorable origin characteristics and overall roast quality will improve.

The initial stage of roasting is endothermic, up until 1st pop. As the green beans are heated, they will gradually yellow as their internal temperature rises and water evaporates. The coffee may smell "grassy" at this point. The beans will slowly brown and smell "toasty" as they approach first pop. The roast will also begin to smoke and chaff will separate around 1st pop time, which usually happens when the bean's internal temperature reaches 400 degrees F (204 degrees C). The coffee's sugars begin to caramelize around 370-400F, and continue to caramelize as long as internal bean temperature rises.

First pop is usually obvious, and it sounds a great deal like popcorn popping. Some beans pop quietly, others are almost violent. Water and Carbon Dioxide escape as the bean's cells break down. The roasting process now becomes exothermic, as the beans are releasing energy stored up from the initial heating. The beans will pop for 1-2 minutes on average, and then the roast will return to its previous endothermic state. If the temperature is allowed to stall at this point, the coffee will probably taste "baked" due to interruption of sugar caramelization. One can end the roast at any time after first pop. A roast that finishes between first and second pop is called a "City" roast if it's lighter or a "Full City" roast if it's darker. The origin character of a coffee is highlighted at this roast level, along with any defects in the bean. This is where the highest quality coffees can display their delicate traits without interference from flavors acquired during the roasting process.

If you choose to take your roast darker, you must apply more heat. The beans will continue to expand and smooth after first pop, until they begin second pop, which sounds like crackling cellophane. This is the sound of the bean's woody matrix (cellulose) breaking down under the heat. The coffee is literally beginning to burn. Most of the bean's sugars have caramelized now, lending dark-roasted coffees their pronounced bittersweetness. If the roast continues, oils will migrate to the surface of the beans. If the roast is stopped before or just after oils appear, it's called a "Vienna" or "Continental" roast, which is a balance between Full City complexity and French intensity. If roasting continues and the oils come out on the surface of the bean, this is a "French" roast. A French roast will be smoky, sweet, and have a more intense, but narrower flavor profile than a Full City roast. At this level, flavor defects are hidden by the roast, but origin character and subtle flavors are obscured as well.

Experiment with different roast profiles until you find what's best for a particular type of coffee. Every coffee has a roast "curve" or profile that brings out favorable qualities. If you plot a graph of time vs. temperature during your roast, you'll see exactly what this means. By moving the 1st pop time (as 1st pop temperature remains relatively stable) earlier or later, you can bring out different taste characteristics. Heating the coffee to 1st pop earlier emphasizes the coffee's acidity. By delaying the 1st pop, acidity will be diminished but other flavors may emerge. Work with large differences (1 minute increments) in pop times to begin, and then use smaller margins to zero in on your ideal profile.

The key to improving your coffee roasting skills is consistency. When troubleshooting a roast or experimenting with new profiles, only change ONE variable at a time and observe the result. Changing multiple variables makes it nearly impossible to know which changes caused which results, and even if you do achieve the desired results in one area, other attributes are likely to be undesirable. The same principle holds true for brewing coffee or pulling espresso shots.

Roasting Methods: Skillet Roasting Tools

One needs only a few tools to roast at home. The method which requires the least investment is simply to roast the beans in a heavy skillet or wok over a heat source. This requires no electricity, only sufficient heat, and can be done over a campfire or backpacking stove. Skillet roasting can be aerobic exercise, as the beans must be kept moving to prevent scorching. The major drawback of skillet roasting is its inconsistency of end product compared to other methods. It's still a good method to know, as it's low-tech and portable.

To roast your coffee in a skillet you will need:

1. A well ventilated place - outdoors or a stove with a smoke hood and exhaust fan
2. An iron or copper skillet (or wok, etc.) with a lid
3. Insulated gloves/hot pads, for holding the skillet
4. A thermometer for recording drop (initial) temperature/pop temperature
5. A metal colander for cooling the beans
6. A stopwatch to record elapsed time
7. A notebook if you want to keep a roast log. In the roast log you record data like pre-roast weight, pop time(s) and temperature(s), and tasting notes. This can be tedious, but it's easier to repeat great roasts if you know what you did last time.

Skillet Roasting Process:

1. Begin with a pre-heated skillet, clean and free of oil. Put the lid on the skillet, start your timer, and begin heating over a medium-high heat. The pan should be evenly hot, so take a good 10 minutes or more to pre-heat the pan. When the thermometer reaches your target temperature, turn down/off the heat and let the pan cool for a minute before heating back up to your target temperature. Ideally you'll heat up the skillet around 370F-400F before you add the green beans. However, cast iron retains heat very well, so you may find drop temperatures as low as 350F yield excellent results, especially after multiple consecutive roasts.

2. Weigh or measure your green beans. Volume is fine, but weight is better. You'll want 9-12 ounces (255-340 grams) of coffee for an average roast. More coffee will take longer to roast and consistency will decrease, but if you have a very large skillet it's more efficient to drop larger roasts.

3. Turn down the heat to low-medium, add your beans, and start the timer, then proceed to stir or shake the beans. Gently move the beans back-and-forth so they don't sit in one place and burn. Continue to shake the skillet until you pull the roast!

4. It should take about 5 minutes for the beans to reach first pop. Adjust the heat to change pop times. You can occasionally lift the lid to check the development, but keep those beans moving or they'll scorch and taste ashy. It's a good idea to back off the heat when the beans begin to pop, as it allows them more time to develop before hitting second pop and helps keep them from scorching.

5. Generally the beans should be pulled no more than 4 minutes after first pop (for a Full City) or they'll begin to taste "baked." You can fudge this a little if the beans need more time/heat to develop, or try pulling early and see how your coffee tastes.

5a. For a Vienna or French roast, leave the coffee in the skillet and add a little heat if the beans don't keep developing. You'll have to get the beans internal temperature up to 450F to begin 2nd pop. Generally one can turn off the heat once 2nd pop begins, because further heat will cause the beans to oil too quickly. A Vienna roast should be pulled when the first spots of oil begin to show at the ends of the beans. This is usually 30-45 seconds after 2nd pop begins. A good French roast should be dark but not too oily.

6. When beans are ready, dump them into your metal colander and agitate to cool. You'll need to plan ahead and dump the coffee a little before it's done because it'll continue roasting until it cools enough.

7. Make the proper notations in your roast log, store the coffee, and continue roasting or clean up. Simple.

Roasting Methods: Popper Roasting Tools

A step up from the skillet is a hot air popcorn popper. These can be found for pocket change in thrift stores, and will dramatically increase the consistency of your roasts. Be sure to get one with air vents around the sides of the drum, because models with mesh screens on the bottom could ignite the chaff as it separates from the bean.

To roast coffee in a popcorn popper you will need:

1. A well ventilated place - outdoors or a stove with a smoke hood and exhaust fan
2. A suitable model of popcorn popper
3. Insulated gloves/hot pads
4. A thermometer for recording drop (initial) temperature/pop temperature
5. A metal colander for cooling the beans
6. A bowl to catch the chaff as it leaves the popper
7. A stopwatch to record elapsed time
8. A notebook for roast logging.

Popper Roasting Process:

The popcorn popper usually roasts 4oz of coffee in 5-8 minutes. It's a smaller batch size than a skillet, but very quick and far more consistent. There's no built-in way to adjust temperature, so the machine is on and heating for the entire roasting process.

1. Pre-heat the popper for 30 seconds to 1 minute, but there's no need to "surf" the temperature as with the skillet. Anywhere from 370F to 450F is probably fine. Experiment and find what works best.

2. Weigh or measure an amount of green beans equal to the amount of popcorn kernels indicated by the manufacturer. The maximum is usually 4oz (113 grams).

3. Drop the beans, start the stopwatch, place the chaff bowl under the popper opening (where popcorn would come out) and sit back.

4. The beans will develop quicker than in the skillet, and should begin 1st pop around 3-4 minutes.

5. Watch closely after 1st pop, and be sure to pull the roast a little before you think it's ready to compensate for cooling time.

5a. Keep roasting if you want a darker roast.

6. Unplug the popper and dump the beans into your colander, and shake or stir until cool.

7. Store, and keep roasting or clean up. Make sure to take good notes along the way!

Commercial home roasting machines are available, and what you're paying for is consistency and repeatability, but unfortunately commercial roasters still fall short of professional roasting machines. The popcorn popper is an unbeatable price/performance ratio for the home roaster. One can roast several years on a popper before a commercial roaster will improve the consistency of one's roasts.


Try some new coffee cooking with all those beans you've got now.

Cthulhu's Revenge

A chaotic espresso drink fit to summon eldritch horrors from the cyclopean depths of one's psyche or call down unnamable madness from the outer spheres.

The secret to this drink is to intuit the measurements. You'll probably need to make it a few times to get it right, but what's great is that it'll always be a little different every time. Cthulhu's Revenge is properly made with Robusta or a Robusta/Arabica blend to insure a psychosis-inducing caffeine content.

1. If you have access to an espresso machine, make a double shot or two. If not, make a small amount of double-strength coffee in a French press. Make more coffee if you like but always err on the side of making the coffee strong!

2. Add honey, dark chocolate or cocoa, and optionally nutmeg, clove, cinnamon, powdered chilies, or any spices which seem appropriate.

3. Drink, and repeat if necessary. Not for those who fear a caffeine overdose or have a need to sleep in the next few hours.

Kaldi cakes

Hippie style energy bars after an ancient Ethiopian war bread. Think of it as time-release caffeine with fiber.

This is basically a quick-bread with added green beans. Coffee was originally consumed raw, as a whole cherry. Roasting didn't develop until around 1400AD, so until then green coffee was boiled to produce a bitter drink or ground and eaten with animal fat. Eating the green beans allows the caffeine to be absorbed slowly, meaning you get a longer, but less intense energy lift. These are great for hiking or camping. This recipe is modular, so add or change ingredients to suit your needs or taste. The blade-type coffee grinders are good for pulverizing green beans. Avoid putting green beans in a burr grinder as they could damage the grinder.

Skeleton Ingredients:

2 cups whole wheat flour
2 cups unprocessed bran (wheat, oat, whatever)
1 cup green beans, ground
2 tsp baking powder
1 tsp salt
1/2 cup honey

Suggested Modular Ingredients:

1 cup date, chopped
1 cup walnuts/pecans/almonds, chopped
1/2 cup chocolate (chips or chunks)
1 tsp cinnamon, ground
1/2 tsp cardamom, ground

Combine dry ingredients in a mixing bowl. Add 1/2 cup warm water to the honey, and mix, then add to dry ingredients. Knead the dough and continue to add warm water until the dough is moist, but not sticky. Bake approx. 40 minutes at 325F (163 C). These work well in muffin tins or other small baking tins, as they cook more evenly and make better snacks. It's a work-in-progress, so play with the recipe, adding a fat or using raisins instead of dates...you get the idea. - Tychoseven

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