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In modern society, coffee is not only used to refresh oneself, but more of a lifestyle. The emergence of decaf coffee on the market to satisfy those who have difficulty sleeping due to caffeine intake, or those who love coffee but do not want to consume caffeine, is undoubtedly a very good choice.

After the emergence of decaf coffee, many people questioneddecaf coffeewhether it would affect health and so on. Front Street believes that questioning anything apart from the amount consumed is nonsense. Whether it is caffeinated coffee or low-caffeine coffee, if the daily intake exceeds what the human body can handle, even drinking water will cause corresponding problems. Therefore, Front Street wants to remind all coffee-loving friends that although coffee is delicious, do remember not to be greedy. Alright, back to the point, what is decaf coffee, and how is decaf coffee made? For this reason, Front Street has obtained and listed a Colombian decaf coffee bean to explore together with everyone.
 

What is decaf coffee?Decaf coffeeIs it really zero caffeine?

Generally, the caffeine content of coffee beans is measured by weight ratio. Arabica coffee beans have a caffeine content of 0.9%-1.4% (average 1.2%), while Robusta has 1.8%-4% (average 2.2%). Decaf coffee is divided into naturally low-caffeine coffee and artificially processed decaffeinated (decaf) coffee. The more common naturally low-caffeine coffee is Coffea Laurina, whose caffeine is half that of ordinary Arabica (0.6%).

Unlike other artificially processed decaf coffees, Coffea Laurina has a lower caffeine content than ordinary Arabica coffee trees due to genetic degeneration, and its flavor is even better. As for artificially decaffeinated coffee, the European Union's standard for this type of decaf coffee is that the caffeine content after processing does not exceed 0.1% of green beans, while the U.S. Food and Drug Administration FDA standard is to remove it to below 3% of the original caffeine content.
 

Does decaf coffee mean it is completely caffeine-free? Not exactly. Front Street Coffee (FrontStreet Coffee) believes that although decaf coffee has extracted a large amount of caffeine, 2% to 3% of caffeine still remains, meaning each cup of decaf espresso will still contain about 0-7 mg of caffeine. Although caffeine is still present, compared with ordinary espresso, the caffeine in decaf coffee will not have any effect on the vast majority of people.
 

How is caffeine extracted from decaf coffee?

With the development of the coffee market, there are many methods for removing caffeine, which can broadly be divided into direct/indirect solvent processing, supercritical carbon dioxide processing, the Swiss Water Process, and the mountain spring water process.

Direct solvent processing (direct contact method)

The direct solvent processing method uses chemical solutions such as dichloromethane and ethyl acetate to dissolve out caffeine. First, steam is used to open the pores of the green coffee beans, and the dichloromethane solvent is added directly to the coffee beans. After the solvent combines with the caffeine, the caffeine-filled solvent is washed away, and the coffee beans are steamed again to remove all residual solvent. Because dichloromethane is suspected of increasing cancer risk with long-term exposure, there are concerns about using it as a solvent. But in fact, the FDA limits the dichloromethane content in decaffeinated coffee to 0.001%, and in reality it is even lower than that, with very little side effect.

The process using ethyl acetate as a solvent is the same. Ethyl acetate usually comes from sugarcane, so when used, the direct solvent method is sometimes called the sugarcane decaffeination method. Usually, decaffeination processing in Colombia uses this method. However, ethyl acetate is a highly flammable substance, so it is relatively dangerous.

Swiss Water Process 

This is the most traditional method of extracting caffeine, using this commercially developed high-efficiency processing method.
 

Steps of the Swiss Water Process: Soak green coffee beans in hot water. In the Swiss Water Process, this hot water is called "Flavor-charged Water." This water contains saturated flavor factors that should be present in all green coffee beans, except caffeine. This special water is the most important medium in the subsequent decaffeination process. After the flavor-charged water is formed, the coffee beans are filtered out. The flavor-charged water is passed through an activated carbon filter to remove caffeine, and what remains is hot water full of pure flavor factors. Then the filtered coffee beans are soaked again in the hot water full of pure flavor factors, allowing the coffee beans to reabsorb the coffee flavor.

Supercritical carbon dioxide processing

This processing method first allows the coffee beans to absorb water and swell, causing the caffeine molecules in the coffee beans to become loose. Liquefied carbon dioxide is added and a pressure greater than 100 atmospheres is created in the water. Carbon dioxide is highly selective and will not "harm" the carbohydrates and proteins in the coffee beans while dissolving out caffeine, ensuring that the flavor of the coffee beans is not damaged. The liquid carbon dioxide that has carried away the caffeine can also be recycled after removing the caffeine.

Coffee made by decaffeination with carbon dioxide places a lower burden on the human body, and according to research, this method extracts more caffeine than the direct solvent method. At the same time, the cost of this method is much higher than that of the direct solvent method.

Mountain spring water process

Very similar to the Swiss Water Process, this uses another special type of water, water taken from glaciers, to extract caffeine. The company Descamex states that they use some kind of special filtration device to remove caffeine. After processing, a caffeine-free water-based solution is obtained. This solution also dissolves the solid substances of coffee and can be reused in the decaffeination process.

Does decaf coffee taste bad?
Based on the decaf coffee processing methods above, Front Street Coffee (FrontStreet Coffee) believes that decaf coffee tasting bad is not caused by the processing. This is because most decaf coffee already chooses some cheap, commercial-grade coffee beans as its raw material. Modern decaffeination technology is quite complex. In most cases, companies producing decaf coffee will naturally tend to choose coffee bean varieties with higher caffeine content when selecting raw materials (such as Robusta beans). Even before the decaf coffee beans undergo decaffeination, the coffee beans themselves were already not tasty. Like other coffee beans sold in coffee shops, if decaf coffee beans start as high-quality Arabica coffee beans from the very beginning, then even after decaffeination, the decaf coffee can still perform very well.
 

Front Street Coffee (FrontStreet Coffee) representative coffee bean — Colombia Huila Swiss Water Process Decaf Coffee
 

Country of origin: Colombia

Region: Huila

Altitude: 1,750 meters

Varieties: Typica, Caturra, Castillo

Processing method: Swiss Water Process

Grade: Supremo

Harvest season: 2020

Colombia Huila region

Colombian coffee beansare extremely well known in the world, and the high-quality washed beans they produce have always been a representative of high-quality coffee. Coffee beans exported from Colombia undergo density inspection and manual removal of defective beans, and are bagged only after strict inspections at every level. Therefore,Colombian coffeequality can be guaranteed.
 

Colombia Huila belongs to the specially selected high-mountain coffee beans of the Colombian national company, and is known as a national treasure of Colombia. Relying on superior geographical and climatic conditions, Colombian coffee has always maintained relatively high quality. Usually, Colombian coffee beans without a special market trademark name all come from the National Federation of Colombia Coffee Growers, which has always been known for strict quality control and active promotion.

Colombian decaf coffeeBean varieties
This batch of decaf coffee includes three coffee varieties: Typica, Caturra, and Castillo. As one of the oldest Arabica varieties in the world, Typica is deeply loved for its delicious and sweet flavor, but because of its low yield per unit, it has been replaced by many high-yield coffee varieties in Colombia. Caturra is a natural mutation of Bourbon, and its flavor is comparable to or slightly inferior to Bourbon beans. More importantly, it has extremely strong adaptability and does not need shade trees. It can thrive even under direct sunlight, commonly known as Sun Coffee, and can adapt to high-density planting.

Castillo is based on the Colombia variety and was crossbred with Caturra, only succeeding by the tenth generation. Although it was not favored by industry practitioners when it first appeared, in recent years there has been no shortage of batches with elegant and delicate flavor on the market.

Green bean grade
The grade of this batch of green coffee beans is Supremo. In the Colombian coffee bean system, Supremo is the highest grade, while Excelso is smaller in bean size and more ordinary. Colombian coffee beans have a balanced flavor profile, a rich mouthfeel, unique flavor characteristics, and a relatively full body. At medium roast, the flavor carries a sweet note of vanilla and dark chocolate.

How Front Street roastsColombian decaf coffee beans
Front Street's roaster used medium heat and then steadily increased it. The yellowing point was around 6 minutes 15 seconds, then the heat was lowered and the air door was opened to enter the Maillard reaction. At first crack, the air door was opened wide, the heat was maintained, and the temperature was about 183.2°C. The beans were discharged 2 minutes 30 seconds after first crack.

Preheat the roaster to 200°C and load the beans, set the air door to 3, turn on the heat after 30S, adjust the heat to 130, the turning point is 1'32'', maintain the heat, 6'15'' yellowing, the grassy smell disappears, entering the dehydration stage, raise the heat to 140, open the air door to 4, and when it reaches 151°C lower the heat again to 110.
 

After 8 minutes, dehydration is complete. The bean surface shows wrinkles and dark patches, and the toast aroma turns into coffee fragrance, which is the prelude to first crack. At this time, keep the heat unchanged, open the air door to 5, and listen carefully for the sound of first crack. At 9'57'', first crack begins, and the air door is fully opened to 5. The development time after first crack is 2 minutes 30 seconds, and the beans are discharged at 194.2°C.

Front Street cupping report
 

Front Street brewing recommendations

Dripper: Kono dripper

Water temperature: 90°C

Dose: 15g

Coffee-to-water ratio: 1:15

Grind size: medium-coarse grind (70% passing rate on China standard No. 20 sieve)

Brewing method: three-stage extraction. Use 30 grams of water for blooming for 30 seconds, pour in a small stream in circles until 125 grams for the first stage, and when the water level is about to expose the coffee bed, continue pouring until 225 grams and stop pouring. When the water level is about to expose the coffee bed, remove the dripper. The brewing time is 3 minutes.

Brewing flavor: dark chocolate, caramel, nuts, rich mouthfeel.

The above content is compiled by CoffeeHunters, a coffee news website.