Crisp noodles are the obvious or not obvious cracks and broken strips on the surface of dried noodles, which are mainly shown as follows: it looks self colored and rough, has a crisp texture and is easy to break, the section is very irregular when breaking, the breaking sound is low or silent, there is no elasticity, the Flexural strength is poor, and it breaks into small segments when boiling with water. The serious consequences mainly include a decrease in the edible quality of dried noodles, a decrease in the rate of authentic products, which mainly leads to unqualified bending and irregularity of the products, resulting in a large number of broken bars. A large number of broken bars return to the machine, which in turn affects the quality of the next batch of noodles, easily leading to cognitive cycle, increased energy consumption, and increased costs.
1、 The Reasons for the Production of Crispy Noodles
1. Improper control of drying process
The main purpose of the stick noodles production line in the drying room is to remove excess water from the wet noodles, fix the structure and shape of the noodles, maintain the cooking performance of the noodles themselves, and facilitate storage, sales, and consumption.
The drying process of dried noodles is a process of mass and heat transfer. The surface of wet noodles receives heat from the surrounding air, causing its surface moisture to evaporate and be carried away by the hot air, which is called "surface evaporation". The phenomenon of heat transfer from the outside to the inside and water molecules diffusion from the inside to the outside also occurs inside the noodles, which is called "internal diffusion". If the speed of "surface spreading" and "internal diffusion" is equal, noodles are less prone to quality problems.
Mixed noodles are made by rolling through multiple rollers, with a high density and resistance to diffusion of water molecules from inside to outside. Additionally, wet noodles have a low thermal conductivity, poor thermal conductivity, and slow heat transfer. The kinetic energy of water molecules inside the noodles is small, resulting in a slower "internal diffusion" speed. The surface of wet noodles has a large contact area with dry media, absorbs more heat, and has a higher molecular kinetic energy, resulting in a faster "surface evaporation" speed. Therefore, wet noodles have the characteristic of faster surface drying than internal diffusion, and are prone to the phenomenon of faster surface drying and slower internal drying during the drying process.
If the temperature is raised and moisture is removed too early in the early stage of drying, it will cause the surface of the dried noodles to contract and form a film, sealing the internal diffusion channels of water molecules. In this case, if heating continues, the water inside the dried noodles will vaporize, expand many times in volume, and generate steam pressure. At the same time, due to the fact that surface evaporation is faster than internal diffusion, surface shrinkage is greater than internal shrinkage, and the shrinkage varies in various directions of inner and outer length and width. Under the action of different shrinkage forces, a stress of varying magnitude and direction is generated inside the noodles, thereby weakening the strength of the noodles themselves. In this way, under the combined effect of contraction force and steam pressure, the noodles will crack in areas with poor mechanical strength, forming a crispy surface.
2. Excessive or insufficient dehydration of wet noodles
If there is too little water loss during the drying process, the moisture content of the dried noodles will be higher than the equilibrium moisture in the atmosphere. During the storage process, the drying of the dried noodles will continue, which can easily cause an imbalance of moisture inside and outside the noodles, resulting in crispy noodles. Practice has proven that high concentration water noodles do not have any problems before entering the finished product warehouse, but are only exposed during storage or in the hands of users. On the contrary, if the noodle loses too much water, it will damage the adhesive state of the noodle tissue, leading to an increase in the brittleness of the noodle and a loss of elasticity. This type of noodle is not resistant to handling and heavy pressure,
3. Seasonal factors
In winter, when the temperature is low, there are often more cases of producing crispy noodles. The temperature is low and the wind speed is high. When the noodles first leave the micro room, it is obviously much higher than the temperature, forming a large temperature humidity difference. The noodles suddenly come into contact with dry and cold air, which is prone to severe shrinkage, bending and deformation, often causing a large number of crispy noodles. Many manufacturers have had this experience.
4. Quality of wheat flour
Wheat flour is the main raw material for the production of dried noodles. Factors such as poor quality, low gluten, long or short storage time can all cause quality problems in dried noodles. Some manufacturers pay attention to the content and quality of wet gluten in wheat flour, but neglect the content of cellulose. Due to the high water absorption rate of cellulose, high content will prioritize water absorption. It affects the uniform water absorption of starch and egg itself, causing the formation of gluten network to be not good enough, resulting in crispy noodles. In addition, cellulose has no plasticity and elongation, and its high content can easily cause crispy noodles to appear.
5. The impact of previous processes such as dough blending, ripening, and tablet pressing
Due to factors such as improper water addition rate during dough mixing, shortage of additives, especially salt, short ripening time, sparse or dense tablet pressing, wet noodles with poor natural conditions before entering the drying room have poor mechanical properties during the drying process, making it easier to produce crispy noodles.
6. Impact of production equipment
The type and rotation speed of the dough mixing machine, the number and finish of the pressure rollers of the Tablet press, and the precision of the surface knife of the slicer are all important conditions to ensure the tenacity, strength, smoothness, and tidiness of the noodles. Otherwise, the production of noodles with many bumps, burrs, etc. are hidden dangers of crisp noodles.
7. Improper storage
Hangmian has strong moisture absorption. Especially during the rainy season and cloudy weather. Exposed to the air, dried noodles can easily break due to moisture absorption and moisture regain. Therefore, negligence in the packaging, packaging, and transportation of dried noodles is also the cause of the pastry.
8. Other factors
The size of the wind force in the drying room, the stability of temperature and humidity control, the spacing between the fixed rods of dried noodles and the running speed of dried noodles in the drying tunnel all have an impact on the drying quality of dried noodles. The technical operation level and strain capacity of workers will also affect the quality of noodles.