Coffee roaster three heating methods

1. Air flow

To put it simply, an air-flow bean dryer is like a hair dryer, sucking in the air with a fan, then raising its temperature through a heating coil, and using hot air as a heating source to bake coffee beans. the hot air can not only provide the temperature needed for baking, but also use the power of the air to stir the coffee beans, killing two birds with one stone.

The advantage of air flow is its high heating efficiency, so the baking time is short, which can be completed in about five to eight minutes. This is the advantage that large bakeries like to use. But the disadvantage is that the heating efficiency is too high, which makes the heating too fast, so it is easy to cause the roasting degree of the outer layer of coffee beans to meet our requirements, but the center is not enough! In addition, because the baking time is too short, caramelization may not be complete, which is where special attention should be paid to air-flow baking. If the technique is properly controlled, the aroma performance of air-flow roasted coffee beans will be excellent, which is the main reason why many people support air flow.

2. Direct fire type

The direct fire is to heat the coffee beans directly with a flame. Up to now, the "fire" of direct fire not only includes general flame (including gas furnace fire and charcoal fire), but also includes infrared and electric heating pipe. Because of the lack of air flow to stir the coffee beans, direct-fire baking usually requires external stirring of the coffee beans. A batch of coffee beans takes more than ten minutes to bake, and because the temperature is slow, the caramelization of coffee beans will be very complete, and the flavor will be more complex and compact than the air flow. And this is the greatest advantage of direct fire.

When baking with a gas stove or charcoal fire, you should carefully control the distance between the fire and the coffee beans, and try not to let the flame directly touch the coffee beans, otherwise not only the coffee beans are easy to have Jiaoliang, but also have a feeling of anxiety when drinking.

3. Semi-direct fire type

The baking method which combines the advantages of direct fire and air flow is the mainstream of commercial baking machines at present. Semi-direct-fire baking is actually similar to direct-fire baking, but because there are no holes in the outer wall of the baking container, the flame will not directly touch the coffee beans. In addition, the ventilation equipment is added to introduce the hot air from the outside of the baking container into the baking room to improve the baking efficiency. Another function of this ventilation device is to suck out the exfoliated silver skin (the film attached to the outer layer of coffee seeds). To prevent the silver skin from burning because of high temperature in the baking room, thus affecting the taste of coffee beans (some so-called charcoal-roasted coffee is to help prevent the discharge of silver skin. Make the coffee beans smell of smoke.