I. Overview Throughout the production of instant noodles in China, almost frying technology is used. The palm oil needed depends on imports and consumes high fuel, which directly affects economic benefits. Since the three low foods (low fat, low sugar, low salt) have become an inevitable trend in the development of today's food, the market of oil-free instant noodles is quietly emerging, and it will form a spring situation with fried instant noodles. The production of oil-free instant noodles is what kind of process is used.
If the traditional hot air drying process is adopted, it heats the surface of the noodles, heats the surface of the noodles, and gradually transmits and infiltrates inward, so that the internal moisture temperature of the noodles rises and migrates to the surface. Here, the temperature direction is opposite to the direction of water migration. Therefore, the hot air drying time is long, the surface block is severely shrunk, the rehydration is poor, the gelatinization degree in the surface is inconsistent, the turbidity is easy, and the outer color is dark, which affects appetite. The use of high-tech - microwave drying, it uses ultra-high frequency electromagnetic energy to directly interact with the material, so that it is heated at the same time, thus solving the drawbacks of hot air drying, the quality of instant noodles has been greatly improved, and the surface has been increased. The elasticity and toughness, even if it is steamed in the water, and the foaming time is long, it is continuous, not turbid, and the noodles are smooth and delicious. The technology was approved by the national ministry in 1994.
Second, the principle and structure of microwave energy equipment: 1, microwave heating principle. The microwave is an electromagnetic wave having a frequency of 300 kHz to 300 MHz. The water molecules in the material of the heated medium are polar molecules. Under the action of the rapidly changing high-frequency electromagnetic field, the polar orientation will change with the change of the external electric field, causing the movement of the molecules and the mutual friction effect. At this time, the field energy of the microwave field is converted into thermal energy in the medium, so that the temperature of the material is increased, and a series of physicochemical processes of heating and expansion are generated to achieve the purpose of microwave heating and drying. 2, microwave instant noodle drying equipment from the microwave heating principle, due to the microwave action to change the arrangement of starch molecules, remove water, ripening and puffing and other physicochemical processes to achieve instant noodle processing purposes. The oil-free instant noodle drying technology is based on the production line of the fried instant noodles production line, and the frying pan section is removed and replaced by a microwave drying device. It would be better if you blow some hot air.
Process structure The microwave drying device is composed of a microwave heater, a microwave source, a microwave suppressor, a conveyor belt, a mechanical transmission system, a general console, and the like. The microwave heater is a cabinet structure with a furnace door and is easy to clean. It directly converts microwave energy into material to convert microwave energy into heat energy, causing water to evaporate. In order to prevent microwave leakage, a suppressor is installed at the inlet and outlet. (1) The microwave generator is composed of a multi-tube magnetron with a frequency of 2450±50MHz and a microwave output power of 60KW and its power supply circuit. It has a temperature protection, safety protection and cooling system protection circuit. The material is conveyed by a speed regulating motor, a shifting mechanism, a conveyor belt, and the like. The dehumidification system uses a centrifugal fan. (2) The microwave generator is composed of a magnetron with a frequency of 915±25MHz and a microwave output power of 20KW and its independent power supply circuit. It is composed of temperature protection, overcurrent protection, safety protection and cooling system protection circuit. The microwave generator requires 8 to 10 liters/minute of cooling water. The material is conveyed by a speed regulating motor, a shifting mechanism, a conveyor belt, and the like. The dehumidification system uses a 4-72-28A2 fan.
Therefore, the use of hot air system is mainly for products with large water content, and the cost of hot air drying is low. For instant noodle products, after noodle forming and dicing, the water content is large, and the hot air is used to cooperate, and under the premise of ensuring product quality, it is advantageous to reduce costs and improve economic benefits.
Third, the microwave instant noodle equipment features: on the basis of the original fried instant noodle production process line, remove the frying section, plus microwave instant noodle drying equipment. The operating parameters of the equipment structure, the connection interface disposal and the instant noodle production equipment in use are fully matched. The production process has the following characteristics compared with the original conventional process. 1. Heating is rapid, uniform, energy-saving and efficient: traditional hot air, steam, etc. transfer heat from the surface of the material to the inside through convection, conduction or radiation, so the heating rate is slow, the surface is heated unevenly, and the microwave is heated. Different from the traditional heating method, it is the overall heating of the medium, and has selective heating, so the heating is rapid, the heat loss is small, and the heating is uniform. It is 2-5 times higher than the general heating efficiency, and the maximum temperature difference is about 2 °C. The gelatinization degree in the flour surface is improved. The performance index of the equipment is superior to that of similar foreign equipment.
With the funding report, Japan uses microwave-hot air as the final drying of the boiled egg noodles. The system uses a 75 kW, 2450 MHz microwave generator to reduce the surface moisture from 30% at a processing rate of 600 Kg/h. To 13%, the hot air is maintained at 80 °C. According to this data, the dehydration rate is 0.7-0.8kg/kwh, and the dehydration rate of our company's equipment can reach 1.1kg/kwh or more. 2. The product quality has been greatly improved and the economic benefits have been remarkable. The instant noodles processed by microwave technology are fuller than the conventional processing method, the gluten value is improved, the noodle rehydration is good, the color is good, the taste is smooth and elastic. It not only maintains the traditional water surface flavor, but also keeps strips, boiled, and turbid when rehydrating, maintaining the original nutrients. Without the use of palm oil, it saves a lot of foreign exchange, and its economic benefits are remarkable. 3, easy to control, continuous production. Since the microwave power and the transmission speed are continuously adjustable, the manufacturer can adjust the process parameters according to different production process requirements. Because microwave heating is different from conventional heating, it has no inertia and fast reaction speed, so it can be controlled instantly, which can reduce waste, defective rate and improve economic efficiency. 4, sterilization and preservation, extend the shelf life. Due to the thermal and biological effects of microwave heating, it can sterilize and mold at a lower temperature, which not only maintains the nutrient content of the original fabric, but also greatly prolongs the shelf life of instant noodles. 5, the device is small in size and easy to install. The microwave equipment is small in size and does not require civil works, as long as the original instant noodle production line is slightly modified. The microwave equipment can also be designed according to the modified size of the original production line, creating favorable conditions for the technical transformation of instant noodle production.
Fourth, the economic benefit analysis: manufacturers of fried instant noodles, will be accurately calculated, because of the cost of using imported brown tung oil each year. Moreover, the production of oil-free instant noodles will greatly reduce surface slag loss. The class produces 30,000 bags, each batch of 65 grams of fried instant noodles, according to 20 hours of work per day, calculated by 300 days per year, only the above-mentioned expenses will save about 2.6 million yuan per year. Microwave oil-free instant noodle equipment, although one-time investment is larger, it has high efficiency, energy saving, uniform heating, easy control, convenient continuous production, small equipment, convenient installation, improved product quality, etc. Unmatched.
V. Microwave oil-free instant noodles have broad prospects for development: When people have not tasted microwave-free instant noodles, people are worried that no frying scent can be used, and no oil-free instant noodles can open the market? When people taste the microwave oil-free instant noodles, they will realize the recognition and favor of oil-free instant noodles. Microwave oil-free instant noodles change the shortcomings of the existing hot air drying process. The taste is consistent with the traditional noodle flavor, no grease, no grease oxidation, haze problem, long shelf life. If vegetable flour, egg yolk powder, soy flour, etc. are added to the flour, various health-care and functional types of instant noodle foods suitable for children and the elderly can be developed. Deep-fried instant noodles can only be boiled, soaked, and tasted in a single way; oil-free instant noodles can not only be cooked, soaked, but also can be made into fried noodles, cold noodles and other foods. It fully conforms to the development direction of natural green foods such as food variety, low oil, functional type, nutrition and health care, and the consumer's return to nature. The market prospect is very broad. For a long time, China's food industry has lagged behind the international advanced level, mainly due to backward production processes, production conditions and production equipment. In order to improve product quality and strengthen market competitiveness, we must seek ways to improve production technology. Only by adopting high-tech to transform traditional food technology can the backward food industry be out of the trapped area.