Professional coffee roasting | understand the three key factors of the baking curve through the daily roasting process

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Among the factors that affect the taste of a cup of coffee, raw beans account for 60%, roasting accounts for 30%, and extraction accounts for 10%. Good roasting can maximize the personality of raw beans and minimize the occurrence of defective flavors. Come to Qianjie Coffee today to learn about baking:

one

Basic structure of coffee roaster

There are about three kinds of coffee roasters on the market, and there are a variety of commercial coffee bean roasters on the market. Such as PROBAT, Diedrich, San Franciscan, Toper, Garanti, Has Garanti, Joper, Proater, Loris,Fuji-Royal and Bonmac. The Sandou customers in Shanghai, China are also good.

Direct firing (Direct Fire Roaster)

Semi-hot air (Half Hot Air Roaster)

Hot air type (Hot Air Roaster)

Before we start baking, let's take a look at the basic structure of the bean roaster, using the Yang Family Pegasus 600g Bean Roaster (semi-hot air Half Hot Air Roaster).

two

The use of the throttle is to control the air flow and velocity in the boiler.

It is generally achieved by adjusting the opening of a baffle at a certain position of the smoke pipe installed in front of the exhaust fan of the roaster, or some roasters are achieved by adjusting the speed of the exhaust fan.

The size of the throttle will affect the effect of hot air in the boiler on the heating of coffee beans. Under the premise of sufficient heat, slightly increasing the throttle can enhance the effect of hot air on coffee beans, but if the heat is not enough or the throttle is too large, the boiler will lose temperature. Opening the throttle when necessary can more quickly remove the silver skins and particles that make the coffee smell. The size of the throttle will also affect the pressure of the boiler and the development of coffee beans.

three

Three key factors before coffee beans start roasting

Qianjie coffee is recommended to record the data before roasting, the water content, density, origin, treatment method, ambient temperature and humidity in the baking room, etc., and plan your baking curve.

Key one: warm pot

According to the reference, the basic input temperature of the roaster is based on 200 degrees, so the temperature of the boiler must be stabilized above 200 degrees, and the maximum throttle must be set at the throttle. The heating time is about 45 minutes, and the temperature reaches 200-210 degrees after 45 minutes.

If the temperature of the boiler is 210 degrees and we need 200 degrees, then we can close the throttle and make the temperature fall to 200 degrees, and then we can proceed to the next step. Rapid heating is not recommended because in the result of the bean dryer, too much firepower (gas) will only increase the temperature on the surface of the boiler, not the temperature of the whole boiler.

Key 2: determine the temperature of raw beans according to their properties.

Today, refer to Papua New Guinea Paradise Bird, tin card species, for low-density raw beans, so it is not very suitable for deep baking, with refreshing sour taste and fruit aroma, we will choose moderate shallow baking, will focus on the firepower adjustment after the first burst, first determine the condition basis of raw beans, and then determine the baking method, first of all, it is a washing processing method with low density. For 17-year-old beans with 10% water content, the input temperature is set according to the existing raw bean status, so the input temperature is set at 200 degrees.

Key three: firepower adjustment

The process of baking is very tricky. If the fire is too strong, it will be overcooked. If the fire is too weak, it will be overcooked. Coffee beans are roasted internally and externally, and the key point is to control the heat.

Input 550g raw beans, specific operation:

Put the furnace temperature to 200 degrees Celsius, set the throttle to stew for 1 minute, adjust the firepower to 160C, keep the throttle unchanged, adjust the firepower to 160C, drop to 115C and bake to 5oC, 152C, the bean surface turns yellow (Mena reaction begins), the smell of grass disappears completely, dehydration is completed, and the throttle is adjusted to 4 (at this time, water vapor is produced and the throttle is opened to discharge water vapor)

In the 9th minute, ugly Hu wrinkles and black markings appear on the bean surface, and the smell of toast obviously changes to the smell of coffee, which can be defined as a prelude to an explosion. At this time, listen clearly to the sound of an explosion point, and the small firepower remains the same. The throttle is fully open for 5 (when discharged at this time), and the firepower is adjusted to 40 degrees and put into the pot at 191.3 degrees. (belongs to shallow baking)

First explosion stage: open the maximum throttle

The explosion stage is one of the most careful and attentive stages in the coffee roasting process. Previously, because of the constant heating of the coffee beans, the water in the beans changed into a state of steam.

Due to the continued heating in the later stage, the water vapor in the beans and the carbon dioxide produced by the Maillard reaction put a lot of pressure on the cellular structure of the beans. In the end, the pressure was so great that the beans could not bear to break the cellular structure of the coffee beans. Water vapor, carbon dioxide and other substances will gush out from the beans, indicating that an explosion has begun. Therefore, an explosion will produce a lot of smoke, here will open the largest throttle!

Record the baking curve: