How to Roast Great Coffee at Home: Coffee roasting is an art, a favourite job of coffee enthusiasts. Now you can enjoy roasting coffee at home with how to roast delicious coffee by machine and roast by a pan that Helena Coffee shares. Let’s immediately learn this unique and new method with Helena Coffee Vietnam!
The Process Of Transforming Coffee Beans When Roasting
The beans undergo a drastic change in colour and flavour during the coffee roasting process. Because when burning, the moisture in the coffee beans will evaporate, making the coffee beans dry and expand.
Some natural sugars are converted to CO2 during the roasting process. While others are caramelized into complex flavours in coffee.
When the process is complete, green coffee beans will turn into brown coffee beans about 18-23% lighter, while the size will be 50 to 100% larger.
After the roasting process, the coffee will have a particular aroma.
The Transformation Stages Of Coffee Beans When Roasting
Green coffee beans: Even after heating, they will retain their original essence.
Turning yellow: At this point, the colour of the coffee beans will become slightly yellow and have a grassy smell.
Evaporation stage: Steam will rise from the beans because the temperature has increased inside the beans.
First Crack (Cinnamon Roast) – First crack: At this point, we begin the actual roasting process. The sugar inside the coffee beans is caramelized. You should now hear a cracking “split” sound, similar to the sound of popcorn popping.
City Roast: After the first crack, the beans have reached the City Roast stage, the minimum roast level to brew coffee.
City Plus Roast: At this point, the coffee beans swell. This is a roast level commonly used for many brewing methods.
Full City Roast: After the City Plus phase is Full City. The coffee beans will prepare to generate the second crack sound at this level.
Second Crack (Full City Plus Roast): The coffee beans will make a second crack when heated to this temperature. At this stage, the coffee flavour will reach its maximum.
Dark Roast (French Roast): At this stage, the sugar in the coffee will be burned off. However, the taste remains. This is the maximum limit of the roasting process and gives the best flavour.
Burning: At this stage, the seeds smell like they are being burned.
Coffee Roasting Levels
Light Roast – Light roast degree
Light Roast is known as Light City, Half City, and Cinnamon Roast. To achieve a light roast – Light Roast, the internal temperature during roasting must be between 356 – 401°F (equivalent to 83 – 128°C), which tends to fall around the beginning of the first crack, at the time. At this point, the surface of the coffee beans is still dry, and the beans are pretty thick and hard.
You can choose this roast if you prefer coffee with higher acidity or a brighter colour. At this roast level, your coffee will have a slightly sour taste.
Medium Roast – Medium roast level
For a medium roast – Medium Roast, including City and City plus, you can set the temperature to 410 – 428°F (equivalent to 137 – 155°C).
Coffee beans will still have a relatively dry surface but are more distinct from the original green beans. This roast occurs from the middle to the end of the first crack.
This roast is more popular than Light Roast due to its medium acidity. The cup of coffee is now less sour and begins to have a stronger coffee flavour.
Medium Dark Roast – Medium dark roast
The degree of roasting is medium dark when the temperature is between 437 – 446°F (164 – 173°C). You may notice oil patches when the coffee beans make a second crack.
This stage is known by other names: Full-City, Full-City+, Vienna Roast. The flavours begin to stand out more for the best cup of coffee.
Dark Roast – The degree of dark roast
To the highest degree, French Roast, Italian Roast and Espresso Roast are all considered dark roasts. The roasting temperature is about 464°F (equivalent to 191°C).
You must keep the temperature below 482°F (209°C) to avoid turning the beans into charcoal. At this time, the cup of coffee has a strong bitter taste.
How Long Does It Take To Roast Coffee?
Determining the exact time it takes to roast a batch is complex, although roasting takes an average of 12 to 20 minutes.
This also depends on the roaster you use and the type and quality of coffee beans being roasted, the temperature ranges from 180 to 250 degrees Celsius.
In addition, the coffee roasting depends on the finished coffee sample. For example, if we roast filter coffee, it will be different from coffee roasting for machines.
When heated, the coffee beans are light brown, changing their original colour from light green to brown. They also change their size and become dehydrated. Towards the end of that process, the essential oils release their fragrance.
How To Roast Good Coffee With A Machine
Buy unroasted green coffee beans.
However, if you are roasting coffee for the first time, you probably have no experience with the type of coffee you like. Therefore, it is necessary to buy a moderate amount for testing. Then you can buy more if you like the coffee.
Prepare coffee roasting equipment.
Currently, there are small coffee roasters on the market that are suitable for roasting coffee at home.
Depending on your needs, you can choose the right coffee roaster for your family at various prices and brands.
Start roasting coffee
When roasting coffee with manual roasters at home, it is impossible to measure the beans’ internal temperature to finish the roast. However, you can rely on the crack to prepare the end of the roast. Specifically, the roasting steps are as follows:
Preheat the roasting cage for 6-7 minutes before placing the coffee in the cage. You can check by inserting your finger into the centre of the roasting cage. If you feel burning after 3-5 seconds, then the temperature of the roasting cage is enough to put green coffee in.
Adjust the gas so that the first crack (First Crack) is about 8.5 minutes. You should experiment a few times with low-priced coffee to gain experience adjusting the amount of gas so that the noise occurs at this time.
Immediately after the first crack, you reduce the heat and prolong the roasting for about 2 – 2.5 minutes: Suitable for pouring Pour over.
Roast until 4:00 – 4:30 after the first bang: Suitable for Syphon, French Press.
Roast until 5:00 – 6:00 occurs the 2nd explosion (Second Crack).
Roast more 1:15 to 2:30 after the second bang: Suitable for mixing filter, Espresso. Depending on the taste, prolong the roasting time accordingly.
Note when roasting coffee.
- Depending on the coffee type and primary processing method, the time for the explosion may vary slightly.
- For Robusta coffee, it is difficult to notice the first explosion. In contrast, the first explosion occurs very clearly in Arabica coffee.
- You can also end the roast based on the colour scale. If you are familiar with roasting, you can clearly notice the correlation between roasting time and colour scale.
Depending on the purpose of roasting, you can finish the roast at the right time. You can study the flavour variation of coffee by roast level to decide when to finish roasting.
Cool down the coffee beans after roasting
Once satisfied with the roast level, it’s time to take out the coffee. You need to use a blower to quickly remove the silk skin and cool the coffee. Usually, the cooling time is shorter than 5 minutes to avoid salting.
Storing and using coffee after roasting
Coffee after roasting, there is a lot of CO2 released as they break down the grain structure in the first 24 hours. Therefore, as soon as roasting is complete, the coffee bag will swell if you pack it right away, causing the seam to open.
However, if you keep the coffee outside for 24 hours, it will lose its characteristic aroma. Therefore, it is best to pack packages with a one-way valve so that the inside air escapes and the outside air cannot enter.
How To Roast Coffee At Home With A Pan
Materials and tools
The first material you need to prepare is coffee beans: you should choose pure coffee beans (coffee has many types such as Arabica, Robusta, etc., and the typical coffee in Vietnam is Robusta (no sour taste)).
Next is butter (fragrant butter, butter, rite butter,…), brandy (you can roast pure coffee beans, but if you want fatter coffee, If the taste is more delicious, prepare more of these ingredients).
You use a large or small pan or saucepan depending on how much coffee you need to roast. You can also prepare a coffee grinder or a manual grinder that will be used to grind the coffee when it is finished roasting.
How to roast coffee with a pan
There are many ways to roast coffee at home. You can roast coffee with a pan or saucepan or use specialized tools like a coffee roaster.
Here is a step-by-step guide to the most straightforward home roasting of coffee beans with a pan that anyone can make.
Processing coffee beans
After buying coffee beans, you should remove the husk to clean, then dry the coffee 1-2 times in the sun to dry; this helps to reduce the roasting time.
Put the coffee beans into the hot pan, and stir constantly and evenly until the coffee is cooked evenly. After about 15 minutes, the coffee beans turn slightly yellow and dark yellow. When you hear the coffee crackling incoherently, you turn down the heat and continue to stir.
When the coffee starts to crack more and more regularly, you put on high heat to increase the temperature to 220 – 240°C to help the coffee ripen and smell. At this time, you will see more smoke; the aroma will start to rise.
Make cold coffee
After turning off the stove, quickly pour the coffee into a wide-sided tray or a well-ventilated place, and use a fan to cool the coffee. This step helps the coffee to smell for a long time, preserving the aroma of the coffee.
- Start roasting the coffee at about 120°C. The temperature to ensure the coffee is cooked without burning is about 180-240°C.
- Roasting time: Each batch does not exceed 60 minutes, usually about 40 minutes (depending on the moisture content of the coffee and the taste the user wants to enjoy).
To get a delicious cup of coffee, you can make coffee the traditional way with a filter. In addition, for quick and convenient brewing, it can be brewed with a coffee machine.