Professional coffee roasting hand net baking bean practical experience sharing introduction to the preparation of hand net baking equipment

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Baked beans with hand net

Enter the field of baking beans, by the least investment, equipment to obtain the most convenient, but the baking skills are relatively high, the failure rate is also relatively high hand network baking hands.

Before we begin, use a mental map to understand the relevance of the whole baked beans.

Equipment preparation:

Gas stove: kitchen gas stove or cassette stove

Timer: either a special timer or a mobile phone

Scale: scale for cooking, for weighing raw beans and cooked beans

Hand screen: special hand net for baking beans or simple stainless steel filter for household hardware

Digital thermometer and probe: optional, some can assist in monitoring the stability of baking

Upper cover: optional, you can use another hand net as the cover, or you can use steaming plate, pot cover or hand net to wrap aluminum foil, etc., the purpose of adding the cover is to maintain the stability of the temperature in the hand net.

Cooling net and cooling fan: quickly cool beans after drying, you can go to the family hardware store to buy your own materials and make them easily.

The two hand nets are 69 yuan each, one uses chopsticks at the bottom to press three lines to increase the bean rolling, the other folds the net as the top cover to prevent the beans from flying out, and the tail end is hooked with stainless steel wire and then clamped with two clamps. Then bake in a cassette stove in order to clean up the kitchen.

Self-made cooling fan and cooling net with high negative pressure cooling efficiency

Another hand net is used as a cover and covered with aluminum foil in order to maintain the stability of the temperature in the hand net and improve the success rate.

What is a flame?

Before we start baking, let's have a little exchange of ideas, which is helpful for further study. What exactly do we think flame is? According to Wikipedia's definition:

A flame, flame, or flame is the glowing and heating [gas region] generated by the combustion of a combustible substance. The flame can generally be divided into three layers: the inner layer is called inner flame, with blue, because of insufficient oxygen supply, incomplete combustion, with reduction effect, so it is also called "reduction flame"; the middle layer is bright, the temperature is higher than the inner layer; the outer layer is called colorless flame, because the oxygen supply is sufficient, the combustion is complete, the temperature is the highest, with oxidation, so it is also called "oxidation flame".

Of course, flames also emit radiant heat, but because the receiving and emission of radiant heat is affected by the color and surface conditions of the object, for example, the reflection of polished copper to radiant heat is up to 97%, which is too complex, and the air is the radiant heat, and only greenhouse gases such as CO2 can absorb part of the radiant heat, so the heat transfer in the bean baking process is ignored.

The problem is, the gas flame heating the stainless steel hand net, no matter whether the flame touches the hand net or not, what is the main way of heat transfer? Conduction? Convection? Radiation?

Yes, it is convective heat, and it is natural thermal convection (if the fire burns to the net and thinks of it as a flame gas, it can be transmitted directly to the net). Therefore, the priority difficulty for beginners in hand-net baking is how to bake evenly and not to coke in the face of high-temperature heat of fire, to solve the problem of firepower and hand-net techniques, or simply hand-net-wrapped aluminum foil to enhance the environmental stability faced by beans.

Baking implementation

We know that there are three ways of heat transfer: conduction, convection and radiation, simply baking beans with a hand net, and facing these three modes of heat transfer at the same time, that is, the heat source is too complex, it is easy to get out of control, resulting in bean charring or uneven baking.

When learning the hand net, in order to simplify the operation, it is recommended to fix the firepower, and then use the distance between the net and the fire source to control the heating degree of the beans.

The heat of the gas fire source can reach 700C or even more than 700C. If the net is directly burned by the external flame, it is usually difficult for the beans not to be scorched. A distance from the fire source is a reasonable method, but as soon as it leaves the scope of the flame, it becomes the natural convection of radiation and air. The intensity of radiation is inversely proportional to the square of the distance, while convection is more difficult to estimate its convection coefficient. In addition, there are various genres of hand-shaking methods, such as left and right, front and back, circle, throw, and tambourine, which will cause the baking environment of beans in the net to be unstable, and the beans will not be easy to bake, or lack of homogenization.

In view of the above situation, the improved method is to cover the hand net and cover the outer layer with aluminum foil, that is, the beans must face three complex heat sources and become semi-direct fire, and the aluminum foil first absorbs the heat energy. then transfer the heat energy to the net and the air in the net, as long as the beans in the net face the conduction heat of the net. And rolling in the hot air formed in the covered hand net to absorb part of the convective heat, even if the bean baker has a slight error, the environment faced by the bean will not vary too much, thus improving the success rate of baking and the quality of the baked bean. If beginners want to reduce the frustration of hand net baking, they can try to cover and cover the net with aluminum foil.

But compared with baking beans with instruments such as snow pans, what is the difference between this way and the fact that the net is lighter than the pot? The bottom of the net can press a groove to promote the rolling of beans, but a thinner pot can have the same effect with a knock. If you really want to say, the surface baked by the net will be more beautiful, because the pot does not have a mesh to help grind the skin. but both sacrifice the radiant heat of the fire source and most of the convective heat at the same time, and there must be a choice in flavor. A long time ago, some people advocated the baking method of only covering but not covering. The ambient temperature of this method will be much more stable than that of uncovered, and radiant heat and convective heat can also be fully used, but the bean baker's technique must be skillful and stable, otherwise the ambient temperature will still change dramatically.

In order to understand what kind of action will cause a big change in the temperature of the environment, is it up and down? Or is it too much to shake back and forth? According to the results of my measurement, the heat of such a setting directly above the fire source will be very strong, but as long as it deviates from the range of the fire nozzle, the temperature will fall very fast, and if the difference between the upper and lower height is about 5 cm, it will also be nearly 20 degrees. So when shaking the hand net, do not deviate greatly from the range of the flame plane. The smaller the amplitude of the upper and lower shock, the better. Under these two preceding questions, the beans roll more fully. The greater the magnitude of the flavor that can be created.

Put an appropriate amount of raw beans (for example, 120g, not too much is recommended, and it is more difficult to bake if the hand load is too heavy) into the hand net without preheating; if the kitchen gas firepower is adjusted to a small fire, if the cassette stove is available for medium fire, hold the hand net at a height of about 10 cm from the fire, and the palm can feel the heat of the fire source from above the hand net, but it will not be so hot as the reference fire power and fire height; press the timer and start shaking the hand net. The method of shaking is to move left and right, shake or translate the circle, the range should not leave the range of the fire source, and try to maintain the stability of the bean baking environment. If you use the pan or tambourine, the temperature difference between the top and bottom of the beans will be too large, unless it is an old hand to change, it is not recommended to operate the hand net in that way.

The most important thing is the control of the baking rhythm, the drying of the 4Rd 30mm 5Rd 30, the browning of the 3Rd 30mm 4Rd 30 into an explosion, and the end of the explosion of the 1RV 30mm 2Rd 00 to cool the beans to the cooling plate. In principle, the flavor of the finished product should not be too bad as long as the starting time of the first explosion is controlled within 8, 00 and 12, which is considered to be up to standard. In order to achieve this goal, the firepower and the height of the hand net from the fire must be appropriate. It is recommended to fix the size of the fire first, and only adjust the height of the fire to control the heating speed during the baking process, which will be relatively simple, otherwise it is easy to be in a hurry to adjust the fire while baking.

Hand net baking because the equipment is simple, to control stability is not easy, more practice to confirm shaking, firepower, distance from the fire is the only way, skilled can bake out the finished product baked by a professional bean baking machine.

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