About coffee roasting

Coffee roasting refers to the process of heating raw beans to convert starch into sugar and acidic substances at high temperature, cellulose and other substances will be carbonized to varying degrees, moisture and carbon dioxide will volatilize, protein will be converted into enzymes and fats, and the remaining substances will be combined together to form an oil film layer on the surface of coffee beans, and in the process, acid, bitter, sweet and other flavors of coffee will be generated to form alcohol and color, and the raw beans will be converted into dark brown raw beans. Because the taste of beans can be changed by small changes in temperature and heat during baking, different beans have different characteristics, and baking is a quick operation in a short time, so it is required to accurately budget the baking process and adjust it in time during baking.

Net spoon roasting is the most economical form of home roasting, using a net spoon in the home kitchen to roast coffee. Net spoon roasting varies according to the amount of beans being roasted, heat, bean seed, room temperature, roasting technique and preference. Take 150 grams of coffee beans as an example, the first explosion usually takes about 10 minutes: the second explosion takes about 15 minutes. If you feel that the heat is easy to control, you can use a thermometer with a probe to control the baking temperature and baking effect.

The operation method and steps of roasting coffee beans with a net spoon:

1) Place the raw beans in a strainer with handles and close the lid tightly. Adjust the fire to medium heat, hold the filter screen 20~30 cm above the fire, and repeatedly swing it evenly in a circular shape to evaporate the water;

2)When beans are heated for 3 to 5 minutes, a small part of the silver skin begins to fall off, and there will be a smelly smell floating out. The silver skin will fall out in large quantities, and the dehydration will soon be completed. There will be a sweet smell. When the sweet taste begins to take on a light burnt flavor, the color of the coffee beans also turns bright yellow;

3)Dehydrated coffee beans continue to roast, issued a "crack" sound, there is a faint white smoke, this is "a burst";

4)About 10 seconds to a few minutes after the first explosion, the coffee beans will emit smoke again, and produce a lighter "crack" sound than the first explosion, which is "two explosions." At this time, the flavor of coffee beans is all released, and the roasting process of coffee beans can be ended;

5)After the second explosion is completed, according to personal taste, you can choose to continue baking or "beans out". After pouring the coffee beans into the plate, use the cold air of a fan or fan to quickly cool them and roast them.

Hand popcorn pots cost more than net spoons, bake better than net spoons, and are much easier to operate.

1)Put the popcorn pot on the gas stove, preheat it on medium heat, and then pour the coffee beans into the pot, the amount of beans is about 200~250 grams. Do not cover the pot lid, in order to facilitate the dehydration process of water vapor emission;

2)Turn the handle at a constant speed to start roasting. When the coffee beans are dehydrated and turn bright yellow, cover the lid and continue roasting.

3)The pan began to crackle and the first explosion began, continuing to bake until the second explosion. The time is generally controlled in 10~20 minutes, usually about 15 minutes is the best;

4)When the second explosion, the lid can be opened properly, and the thermometer probe can be inserted into the pot to control the baking temperature;

5)When the desired degree of baking is reached, remove the popcorn pan from the fire, remove the beans, and cool them with an electric fan.

Electric popcorn machine roaster replaces manual, easy to operate, labor-saving and easy, the quality of coffee beans baked is also uniform and stable. Before using the popcorn maker to roast coffee beans, prepare a thermometer, a net basket for green coffee beans, a container for collecting silver skins, and insulated gloves.

1)Pour 85 grams of coffee beans into the baking chamber of the popcorn machine, start the power switch, and constantly stir the coffee beans with a shovel to avoid uneven dehydration;

2)After about 2 minutes, dehydration is complete and the popcorn maker is covered. Place the container for collecting silver skin at the air outlet and collect the blown silver skin. At this point the coffee beans turn cinnamon;

3)About four minutes later, the explosion began. The first explosion lasts for 1~1.5 minutes, and ends when the temperature of baking chamber reaches about 420℃. If light baking is needed, the baking can be ended at this time, otherwise, it can be continued;

4)Continue baking, 0.5 to 1 minute after the first explosion, the second explosion begins. At this time, the coffee bean surface appears fat, the color becomes dark brown;

5)Second explosion time is short, after the end of the second explosion, coffee beans will be quickly poured into the basket, cooling with an electric fan;

6)After the roasted coffee beans are cooled to normal temperature, the residual silver skin is sieved out and the roasting is completed.

This kind of household baking machine uses alcohol lamp or gas lamp as heat source, and larger ones use flame on gas stove as heat source directly. The advantages of this baking machine are intuitive, easy to control the baking degree, easy to clean silver skin, but the baking temperature is not easy to control.

The operating steps of the hand-operated semi-direct fire roller roaster:

1)In the roasting drum filled with coffee beans, the amount of beans depending on the size of the drum, and then closed the drum;

2) Ignite the fire source, shake the handle at a constant speed, and rotate the baking roller to make the beans in the roller evenly flip;

3)After 3~4 minutes of baking, the beans in the pot began to turn yellow, silver skin off, emitting aroma;

4)Bake to 6~7 minutes, the beans in the pot have become brown, and began to emit white smoke, to 8 minutes or so began to explode;

5)After about 10 minutes, the explosion ended. If you like light flavor, you can produce beans. On the contrary, continue baking, waiting for the second explosion;

6)At 12 minutes, the second explosion is complete, and the beans are quickly released and cooled by an electric fan, and the baking is over.

Operation steps of hot air baking machine:

1)Measure the coffee beans with the measuring cup attached to the machine, place the coffee beans in the roasting chamber and cover;

2)Turn on the power supply, select the corresponding baking time setting on the machine according to your needs, and turn on the switch to start baking;

3)After baking, there is a cooling time of 3~5 minutes. After baking, the indicator light on the power switch goes out, which is the cooling process. After cooling, pull out the socket.

4)When roasting is complete, remove the lid, remove the silver skin collection net, and pour out the coffee beans.