In the era of material scarcity, sweet potato rice, sweet potato Congee, and boiled sweet potato were once one of the staple foods, enabling the villagers to tide over the difficulties of life. Now the economy has developed and become richer than before. Sweet potato no longer plays a major role in people's diet, but people still have indelible feelings for it. In addition, sweet potato belongs to coarse grain, which is more green and healthy than other agricultural products, Dim sum mainly made of sweet potatoes, such as sweet potato cakes, sweet potato meal bags, and inverted steamed sweet potato jerky, are still loved by people. This article shares how to skillfully use a sweet potato dryer to make green food sweet potato jerky The traditional drying system for preserving fruits, vegetables, grains, fish, meat, wood, and other agricultural products is sun drying, which is a free and renewable energy source. However, for large-scale production, there are many known limitations of sun drying, as animals, birds, and rodents can cause damage to crops due to direct exposure to solar radiation, dew or rainwater, as well as dust, dust, or debris. And this system is labor-intensive and time intensive, as crops must be covered at night and in harsh weather, and must be attacked by livestock. Due to uneven drying, it is also possible for insects to infect and grow microorganisms. Solar drying system is the promotion of solar drying, in which products are dried in Closed system with high internal temperature [1]. The main advantages include preventing flies, pests, rain or dust. In recent years, several major attempts have been made to utilize solar energy for drying, mainly to protect agricultural products and benefit from the energy provided by the sun. Crop sunshine is the most common Food preservation method in India and most parts of the world, because the Irradiance of the sun is very high most of the year. Due to the fact that this technology does not require energy during the day, it is more advantageous for small-scale farmers who cannot withstand the drying of electricity or other fuels. If it is necessary to dry the product at night or in harsh weather, additional biofuel heaters can be used for heating
High temperature dryers used in developing countries are economically feasible only in large agricultural sectors. If they are manufactured from locally available materials such as wood and glass, farmers can afford them economically
Sweet potatoes, also known as sweet potatoes, sweet potatoes, sweet potatoes, etc., are harvested in October every year. After excavation, they must be left in a ventilated and cool place for at least 30 days to reduce their internal moisture and increase their sweetness, resulting in a clearer and sweeter taste of the dried sweet potatoes. Generally speaking, the sweetness of red sweet potatoes is higher than that of yellow sweet potatoes, followed by purple sweet potatoes. White sweet potatoes have the highest starch content and rank at the bottom in sweetness. Therefore, it is best to choose varieties with high sweetness when making sweet potato jerky
After selecting a variety, it is necessary to conduct a big PK against the sweet potato itself. Do not want those with wormholes, rotten and moldy, or deformed and unhealthy sweet potatoes! Only select sweet potatoes with intact heads, smooth skin, and excellent appearance, and thoroughly clean them
Pour the washed sweet potato into the steaming pot. It is better to use a high heat first and then a low heat. After the initial steaming, the process of growing the sweet potato in the steaming pot to ripening the sweet potato is the process of its Amylase decomposing into glucose in large quantities at high temperature. No wonder that the obviously raw sweet potato is sweet, glutinous, and this process is also the initial steaming
After heat dissipation, sweet potatoes should be immediately peeled and cut into slices or strips. If cut into slices, the drying or drying time is relatively fast; Cut into strips and blocks to give it a better appearance and texture after drying. Regardless of the cutting method, remember to keep each piece of sweet potato evenly sized and thick. This way, not only will the appearance of the dried sweet potato be consistent, but also the taste will be more stable
The steamed sweet potato chunks are soft in texture, easy to handle, and neatly laid on a tray. If they are dried in the sun, it will take 5-6 days in good weather. Use a sweet potato drying machine and choose a medium to high temperature drying and dehumidification mode. Dry in a drying room at 70-85 ℃ for about 12-15 hours until the moisture content of the potato block is within 20%. This process is the initial drying
After the previous drying, the color, aroma, and taste of sweet potatoes have already improved, but the taste will slightly harden. Then, steam them again, which is also known as steaming sweet potatoes dry. By steaming again, the sugar content and sweet potato aroma are more condensed, resulting in a more fragrant and sweet taste. (When re steaming, white granulated sugar can also be added according to taste)
After the sweet potato is dried and steamed, it is pushed into the sweet potato drying room again. When the water and air are dry, it can be discharged from the furnace. Truly non pigmented, non preservatives added, and free from fly, insect, and mouse contamination in the drying room. After reverse steaming and re baking, the dried sweet potatoes are naturally colored, green and healthy, with a chewy and sweet taste. After steaming and drying 10 pounds of fresh sweet potatoes, 1 pound of dried sweet potatoes can be obtained, and the production process should not be careless. Further steaming and drying can be carried out according to the above steps of initial cooking, initial baking, secondary cooking, and secondary baking, resulting in a better taste
Drying is typically described as the operation of removing moisture by heat to produce solid products. Water is kept in loose chemical combination, exists in the product matrix, and even trapped in the microstructure of solid. Its evaporation pressure is lower than the Vapor pressure of pure liquid, which is called combined water. Moisture that exceeds the bound moisture is called unbound moisture
When a solid is heated and dried, two processes occur simultaneously:
A. Transfer energy (mainly heat) from the surrounding environment to evaporate surface moisture B. Transfer internal moisture to the solid surface and subsequently evaporate due to the application of energy
The drying speed can be controlled by the speed of two processes. As a result of convection, conduction or radiation, in some cases due to the combination of these effects, energy transfer from the surrounding environment to wet solids can occur. The types and designs of various dryers vary depending on the main heat transfer method used. In most cases, heat is transferred to the surface of a wet solid and then to the interior. However, in dielectric heating, radio frequency (RF), or microwave drying, energy is supplied to generate heat inside the solid and flow outward to the surface
Process A removes water vapor from the material surface, depending on external conditions such as temperature, air humidity, and flow rate, exposed surface area, and pressure. Process B, the movement of water within a solid, is a function of the physical properties, diffusion rate, and water content of the solid
Except for weather conditions, The drying behavior of crops during the drying process depends on:
• Product
• Size and shape
• Initial moisture content
• Final moisture content
• Layer thickness
• Opening interval
• Temperature of grain
• Temperature of air in contact with grain, Humidity
• Mechanical or chemical pretreatment
• Air velocity in contact with grain
During drying operations, any of these processes may be a limiting factor in regulating the drying rate, although they all persist simultaneously throughout the entire drying cycle
The sweet potato dry dryer is based on air energy technology, which has a very high energy efficiency ratio and is very energy-saving. The core components of the dryer system include heat pump dryer, drying room, drying fan, control system, etc. Sweet potato drying machine (sweet potato drying machine) is a very mild drying system. The dried products are good in appearance and color. In addition, they are green and environmentally friendly, and do not need to burn coal. There is no pollution. Nowadays, many processing plants and Agricultural cooperative use this heat pump dryer to dry various agricultural and sideline products, such as potato chips, dried radishes, peppers, mushrooms, wild vegetables, ginger slices, honeysuckle, chrysanthemums, roses, Chinese herbal medicine Ginseng, Dendrobium, agaric, mulberry, lotus seed, kudzu root slice, yam, Rice noodles, sausage, etc
