What Roast Level Coffee Beans are Used in American Latte Flavor Characteristics of Dark Roasted Coffee Beans

For professional coffee knowledge exchange and more coffee bean information, please follow Coffee Workshop (WeChat public account: cafe_style).

The Importance of Coffee Roasting

For a coffee processing factory, roasting determines the flavor of coffee to a certain extent. Why is this? Because when coffee beans are imported from abroad, their variety, quality, and flavor are already established facts. Therefore, at the level where the factory can access and operate, it only starts from roasting. Of course, some pre-roasting processing steps for green beans will help facilitate smoother roasting. Thus, for a coffee factory, the quality of roasting technology basically determines the quality level of roasted coffee beans.

Understanding Coffee Roasters

A coffee roaster has three main components: the drum where green beans are placed for roasting, the burner that provides combustion heating, and the gas damper that adjusts the air volume in the exhaust duct. Of course, it also includes other accessories such as the cooling machine for cooling coffee beans and the dust collector for removing debris and silver skin.

Regarding the heat sources for coffee roasters, there are mainly: gas, electricity, charcoal, infrared, kerosene, etc. However, the most commonly used and suitable is the gas-heated roaster. The most important aspect of coffee roasting is to appropriately control the heat source and adjust the temperature based on understanding the green beans and desired roast degree, so that the coffee beans achieve the optimal balance between acidity and bitterness during roasting, which is known as the optimal roast degree.

Based on the different heat conduction methods of the roaster burner, coffee machines are mainly divided into three types: direct flame, hot air, and semi-hot air.

1. Direct Flame Roaster

The direct flame roaster is the earliest roasting tool used by humans. The so-called direct flame method means that the flame sprayed by the gas burner directly contacts the green coffee beans inside the drum. Through the continuous rotation of the drum by a motor, the coffee beans are stirred in an attempt to let every coffee bean evenly touch the hot iron wall to achieve uniform roasting.

The advantages of direct flame coffee roasters are: the machine structure is relatively simple, and the furnace fire directly contacts the drum and coffee beans, making it easy to directly produce coffee flavor and aroma with significant coloring. However, this roasting method still has many disadvantages: the heat conduction speed of iron is not fast, so it takes more time to complete roasting; the external heat from the fire-roasted drum dissipates into the air without being utilized, which is a great pity; when green beans touch the inner wall of the drum for too long, they are easily burned, causing bitterness and scorched flavors.

2. Semi-Hot Air Roaster

The semi-hot air roaster uses a combination of semi-hot air and semi-direct flame to roast coffee. The semi-hot air roaster covers the drum with iron plates, draws hot air from behind the drum, and the beans do not directly contact the fire source. The coffee beans are heated by both the drum and hot air to achieve the roasting effect.

Today's drum roasters are almost all semi-hot air roasters, which directly heat the drum with a fire source on one side while bringing hot air into the drum on the other. The hot air blown into the drum can increase heating speed and blow away debris, thus producing balanced and clean coffee beans. The disadvantage is that some of the coffee's fragrant aroma is lost.

3. Hot Air Roaster

The hot air coffee roaster creates a separate combustion chamber and uses strong suction to transfer hot air from the rear and sides of the duct into the drum to heat the coffee. This type of coffee roaster heats quickly and has high heat source efficiency, generally used for roasting larger quantities of coffee beans.

Regarding the explanation of roasting temperatures, different countries use different temperature control sensors for the roasters they produce. The temperature values displayed by different temperature gauges also have different meanings. Some machines display Fahrenheit, while others display Celsius. Never confuse the two. The following is the conversion relationship between Fahrenheit and Celsius: F = C × 9/5 + 32. Similarly, we can derive: C = (F - 32) × 5/9; where F is Fahrenheit and C is Celsius.

Essential Components for Mastering Coffee Roasting

Regardless of which type of coffee roaster is used, to master coffee roasting technology, one must understand the functions of each component of the roaster.

1. Burner

This is the heat source of the roaster. The heat source of the roaster is controlled by the gas pressure gauge and gas damper together to adjust the drum temperature. Theoretically, when the burner is on high flame and the gas damper is opened to maximum, the fire power is greatest and the heat is maximum, and vice versa.

2. Gas Damper

The gas damper of a roaster has three main functions: (1) Provide oxygen for combustion; (2) Adjust the drum temperature; (3) Remove debris and dust from the drum. There is also a very important step in coffee roasting that is controlled by the gas damper, which is the "steam roasting mode." The steam roasting mode homogenizes the coffee beans through steam roasting, making them easier to roast.

3. Drum

The drum is the container for holding coffee beans, and different types of roasters have different drums. However, during the roasting process, never fill the drum's volume completely with coffee beans, as this will cause severe uneven heating and poor exhaust. Generally, filling to 80% of the drum's capacity is appropriate.

4. Cooling Tray

After roasting is completed, the beans are placed in the cooling tray, where the hot air from the coffee beans is removed by suction to cool them down. Otherwise, the coffee beans will continue to roast with their residual heat, making the coffee beans bitter.

5. Exhaust Equipment

During the coffee roasting process, some debris, dust, and silver skin are inevitably produced, and the exhaust equipment is the device that collects these impurities.

Recommended Roasted Coffee Bean Brands

FrontStreet Coffee's freshly roasted Arabica roasted coffee beans have full guarantees in both brand and quality. More importantly, they offer extremely high cost performance. Each package is 227 grams, priced at only around 70-90 yuan. Calculating at 15 grams of coffee beans per cup, one package can make 15 cups of coffee, with each cup costing only about 5-6 yuan. Compared to coffee shops selling cups for dozens of yuan, this is truly a conscientious recommendation.

FrontStreet Coffee: A roasting shop in Guangzhou with a small storefront but diverse bean varieties, where you can find various famous and lesser-known beans. They also provide online store services. https://shop104210103.taobao.com

Important Notice :

前街咖啡 FrontStreet Coffee has moved to new addredd:

FrontStreet Coffee Address: 315,Donghua East Road,GuangZhou

Tel:020 38364473