| A、Processing technology of dried noodle food
Fine dried noodles are named after the wet noodles are hung on the noodle rod and dried. They are also called rolled noodles and cheese noodles. There are many varieties of vermicelli, generally named according to the width of the noodles or the grade of flour used or the added accessories.
（1）Raw materials and excipients
1. Flour: The wet gluten content of the flour used for vermicelli production should not be lower than 26%. It is best to use special flour for noodles, which should be processed by "Fu Warehouse" (referring to the storage of freshly ground wheat flour in the bunker for a period of time). The main physical and chemical indicators in my country's current industry standards for special flour for noodles are as follows:
|Farinoid curve stabilization time (minutes)≧
|Falling Number (sec) ≧
2.Water: my country has not made uniform regulations on the water quality of noodle making. Generally, drinking water with a hardness of less than 10 degrees should be used.
3.Flour improver: Flour improver mainly includes salt, thickener (such as sodium carboxymethyl cellulose, gul gum, konjac powder, modified starch), oxidizing agent (such as azoformamide, vitamin C) ), emulsifiers (such as monoglycerides, sucrose esters, sodium stearyl lactate) and gluten, etc., should be added as needed. To produce freshly sold wet cut noodles, food can be added.
Pretreatment of raw and auxiliary materials → dough kneading → aging → tableting → cutting into strips → wet cutting → drying → cutting →
Measurement → Packaging → Inspection → Finished Noodles
1.Kneading: The noodle mixing operation requires "four determinations", that is, flour, salt, return machine and other auxiliary materials should be added quantitatively in proportion; the amount of water added should be determined according to the wet gluten content of the flour, generally 25% to 32%. The water content is not less than 31%; the temperature of adding water should be controlled at about 30°C; the dough mixing time is 15 minutes. Winter should be long. Summer is shorter. At the end of kneading, the dough is loose and small particles, which can be formed into a ball by hand, and can be loosened and recovered by light kneading, and the cross-section has a layered feeling. The horizontal linear mixer and the horizontal curve mixer are better for the dough mixing equipment. In recent years, advanced vacuum dough mixers have appeared abroad, but they are expensive.
2.Ripening: Use disc type curing machine or horizontal single-shaft curing machine to ripen, store and divide the dough. The time is generally 10 to 15 minutes. It is required that the temperature and moisture of the dough should not be too different from that after the dough is kneaded. Production practice has proved that the effect of the second curing after the dough is compounded is more obvious, and it has been adopted by domestic and foreign manufacturers;
3.Tablet pressing: It is generally carried out by composite calendering and different diameter rolling. The technical parameters are as follows:
||Calendering multiple：The thickness of the initial pressing dough is usually not less than 4-5 mm, the added thickness before compounding is 8-10 mm, and the final dough is less than 1 mm to ensure that the rolling multiple is 8-10 times, so that the dough is Firm and smooth.
||Roller line speed：In order to ensure the quality and output of noodles, the line speed of the final roll is 30-35m/min.
||Number of rolling passes and rolling ratio：the number of rolling passes is preferably 6-7, and the ideal rolling ratio of each roll is 50%, 40%, 30%, 25%, 15% and 10%.
||Roll diameter： The reasonable method of sheet pressing is reducing rolling, and the roll diameter is arranged in the compound stage, φ240mm, φ420mm, φ300mm; in the rolling stage, φ240mm, φ+180mm, φ150mm, φ120mm, φ90mm.
4. 4.Slicing：Slicing is completed by the noodle knife. The machining accuracy and installation and use of the noodle knife are often related to the defects such as burrs, lumps, twists, drawing, and inconsistent width and thickness. There are integral type and combined type, and the shape is mostly square. The basic specifications are divided into five types: 1.0, 1.5, 2.0, 3.0, and 6.0 mm. At present, round or oval noodle knives have been developed in China, which solves the problem of single strip shape. There is a cutting knife below the noodle knife, which is used to cut the wet noodles horizontally, and the rotation speed can be adjusted according to the length of each wet noodles.
5. Drying：Drying of dried noodles is the most invested and most technical process in the entire production line, and has an extremely important relationship with product quality and production cost. Crispy noodles, wet noodles, sour noodles and other phenomena in production are caused by unreasonable drying equipment and technology, so they must be paid great attention.
The current dry noodle drying process is generally divided into three categories：
||High temperature rapid drying method：This method is a traditional process in my country. The maximum drying temperature is about 50 ° C, the distance is 25 to 30 meters, and the time is about 2 to 2.5 hours. It has the advantages of small investment and fast drying. The disadvantage is that the temperature and humidity are difficult to control. The product quality is unstable, and it is easy to produce crispy noodles, etc., and has been gradually replaced by other methods.
||Low temperature and slow drying method：It is a drying method for dried noodles introduced from Japan in the 1980s. The maximum drying temperature does not exceed 35°C, the distance is about 400 meters, and the time is as long as 7 to 8 hours. This method is characterized by imitating natural drying, stable production and reliable product quality. The disadvantage is that the investment is large, the drying cost is high, and the maintenance is troublesome. It is only suitable for some large and medium-sized factories.
Medium-temperature and medium-speed drying method：In view of the advantages and disadvantages of the high-temperature fast method and the low-temperature slow-speed method, my country successfully researched the medium-temperature and medium-speed drying method in the 1980s and 1990s. This method has the characteristics of less investment, low energy consumption, high production efficiency and good product quality, and has been popularized in China.
Technical parameters of medium temperature and medium speed method:：
Pre-drying—temperature 25-35°C, humidity 80-85%, wind speed 1.0-1.2 m/s, accounting for 15-20% of drying time； main drying—temperature 35-45°C, humidity 75-80%, wind speed 1.5- 1.8m/s, accounting for 40-60% of drying time；complete drying—temperature 20-25℃, humidity 55-65%, wind speed 0.8-0.1m/s, accounting for 20-25% of drying time; medium temperature and medium speed The method is suitable for multi-row straight-run and single-row straight-run drying rooms. The running length of the former should be 40-50 meters, and the length of the latter is about 200 meters. The drying time is about 4 hours.
6. Cutting：The traditional cylindrical paper packaging still widely uses manual labor, which is difficult to achieve mechanization. The new type of plastic sealing packaging has realized automatic measurement and packaging, which is mainly used in the manufacturers of imported equipment, which is the direction of future development.
7. Measurement and packaging：The traditional cylindrical paper packaging still widely uses manual labor, which is difficult to achieve mechanization. The new type of plastic sealing packaging has realized automatic measurement and packaging, which is mainly used in the manufacturers of imported equipment, which is the direction of future development.
8. Noodle processing：Wet noodles should be immediately returned to the dough mixer or cooking machine. Dried noodles can be processed by soaking or crushing, and then returned to the dough mixer. The semi-dry noodles are generally soaked, or crushed together with the dry noodles after drying. The soaking method has good effect and is widely used, but it is prone to acid deterioration. The pulverization method requires that the thickness of the face is the same as that of the flour, and the return amount does not exceed 15%. A small number of manufacturers use a beater to make the dry noodles subject to the double action of crushing and soaking, which has a good effect and is more hygienic.
| 二、Processing Technology of Instant Noodles
Instant noodles are an international convenience food second only to bread. The types of instant noodles are mainly divided into three categories: fried instant noodles, non-fried instant noodles and instant wet noodles. At present, fried instant noodles account for about 90% of the total output, and will remain the leading product of instant noodles for a period of time in the future.
- Raw materials and excipients：
1. Flour：my country has not yet formulated the quality standards for special flour for instant noodles, but considering the chewiness and rehydration of instant noodles, it is recommended to choose flour that meets the following indicators: wet gluten 30% to 32%, and the stable time of the farinoid curve ≧4 minutes, falling number ≧200 seconds, ash ≦0.5%.。
2. Water：The water quality requirements are as follows: hardness ≤ 10 degrees, pH 7.5∼8.5, alkalinity ≤ 50 mg/kg, iron ≤ 0.1 mg/kg, manganese ≤ 0.1 mg/kg。
3. Oil：Palm tung oil is often used as the frying oil for frying instant noodles, and it can also be matched with an appropriate proportion of pork suet to increase the flavor of the product. When selecting oil for frying, the stability of the oil should be considered first, followed by flavor, color, melting point, etc.。
4. Antioxidants：In order to prevent the oxidative deterioration of oil, BHA, BHT, TBHQ or natural antioxidants should be appropriately added to the frying oil.。
5. Surface quality improver：mainly include compound phosphate, table salt, potassium carbonate and soda ash, emulsifier, thickener, gluten, gluten enhancer, eggs, etc. When the quality of wheat flour is defective or high-quality instant noodles are produced, a variety of flour modifiers are often added.。
6. Pigment：Natural pigments such as Xianzi Huang can be used to make the noodles have a nice yellow color.。
（2）Process flow （N/A）
1. Kneading, curing, tableting, and cutting：the process requirements of these processes are the same as those of vermicelli production.。
2. Corrugated forming：The dough pieces are cut into strips by the dough knife and then fall vertically into the corrugated forming guide box, and the corrugation is formed by the slow conveying of the short mesh belt under the guide box. The speed ratio of the line speed of the noodles falling to the line speed of the short mesh belt is usually 7:1 to 10:1, and the density of the ripples is affected by this speed ratio. In addition, the weight of the pressure hammer on the guide box is another factor that affects the corrugation forming. After the short mesh belt is transported forward for a certain distance, the corrugated noodles are unloaded onto the long mesh belt of the continuous noodle steamer, and the speed ratio of the two is about 1:4 to 1:5. In this way, the initially formed tightly corrugated dough strips are drawn relatively sparse and flat, in order to facilitate steaming.。
3. Noodle steaming：Generally, an inclined continuous noodle steaming machine is used, the steam pressure is 0.15-0.2 MPa, the temperature in the machine is 95-98 ℃, the steaming time is 90-120 seconds, and the degree of a-ization of the noodles can reach 85 %above. In order to save land, the multi-layer sand-turning continuous noodle steamer has been put into production.。
4. Flavoring：Some of this process is set between steaming and cutting, and some are set between moulding and drying. It is used to produce seasoned instant noodles by spraying seasoning liquid or dipping.。
5. Cutting, folding and moulding：the cooked noodle strips from the continuous noodle steamer are cut to a certain length by the rotary cutter and idler roller, that is, the quantitative operation of the noodle block is completed. Next, fold the cut noodle block in half at the waist level with the folding guide (it is not necessary to fold in half for the production of bowl-mounted noodles), and enter it into the mold box of the fryer or hot air dryer from the mold-in device. There are two types of die inserting device: six-line parallel die inserting machine and three-line separate die inserting machine. The former is suitable for large factories, and the latter is suitable for small and medium-sized factories.
。 6. Drying：There are mainly two ways of frying drying and hot air drying. It is rare to use high-tech such as microwave drying, quick freeze drying or vacuum drying.。
||Frying and drying：The frying equipment is an automatic fryer, and the main frying technical parameters are: front temperature 130-135°C, middle temperature 140-145°C, rear temperature 150-155°C, frying time 70-80 seconds, The turnover rate of frying oil is less than 16 hours, the oil level is 15-20 mm higher than the mold box, and the moisture of the block after frying is less than 8%. In order to control the deterioration of the frying oil, the acid value, peroxide value, iodine value, etc. Variety. In order to reduce the oil content of the noodle pieces, attention should be paid to the setting of the temperature zone in the oil pan, the water content of the noodle pieces before frying, the frying time, the use of additives, and the noodle piece oil draining device.。
||Hot air drying：The reciprocating chain box dryer is widely used, the hot air humidity is 70-80 ℃, the relative humidity is less than or equal to 70%, the drying time is about 45 minutes, and the moisture content of the block after drying is less than or equal to 12%.。
7. Cooling and packaging：Forced cooling to room temperature or slightly higher than room temperature by blowing air in the cooling machine, then add seasoning soup into the automatic packaging machine, and use composite plastic film (bag noodles) or polystyrene that meets hygienic requirements. Styrofoam (bowl of noodles) completes the packaging, which will be gradually replaced by degradable materials.。
8. Soup preparation：Soup is the key to determine the nutritional value and taste of the product, and it is also related to the grade and grade of the product. The competition of instant noodle brands has actually evolved into the competition of soups. The types of soup can be divided into powder packets, sauce packets and so on according to their contents. The raw materials used are mainly salty seasonings, umami seasonings, natural seasonings, spices, essences, sweeteners, sour seasonings, oils and fats, dehydrated meat dishes, colorants, thickeners, etc. The proportion of various raw materials should be determined according to certain rules and combined with rich seasoning experience. The reference production process of the two soup ingredients in instant noodles is as follows:：
|Powder package：raw material pretreatment → mixing → sieving → packaging → finished product
Meat sauce package：
raw material pretreatment → boiling → mincing → seasoning → heating → packaging → sterilization → cooling → dehydration → finished product
【From Wang Lirong、He Dongping《Technical Guidelines for Storage, Processing and Packaging of Grain, Oil, Livestock and Poultry Products》】