1、 What is semi dry noodles

Semi dry noodles, also known as semi dry noodles, are almost in the early stages of development in China. They are a type of noodles that is close to the middle of fresh and hanging, and their moisture content is also close to the middle of fresh and hanging, usually controlled between 22-26%, so they are called semi dry noodles.

2、 The importance of moisture on semi dry noodles

The drying of noodles requires a certain amount of heat, which is usually supplied by increasing the temperature. Noodles can only vaporize and discharge their moisture content after absorbing heat, achieving the purpose of drying. Therefore, temperature is the driving force behind the exchange of cold and humidity between wet noodles and surrounding media, and plays a particularly important role in the entire drying process of semi dry noodles. However, the main component of noodles is wheat starch, which should be considered a negative phenomenon of cold and wet conductors. Its significant feature is that under natural conditions, the internal moisture content diffuses at a slower rate than the surface moisture content vaporizes. If the temperature is not selected properly, it can cause uneven distribution of moisture content inside and outside the noodles, causing closed conjunctivitis on the surface, affecting drying efficiency, and causing crispy and broken noodles. Therefore, selecting a suitable drying temperature not only affects the overall drying efficiency of the product, but also plays a particularly important role in the quality of the final product.

3、 Principle of Drying Box Method

The drying oven method is also known as the oven drying method or the pyrolysis weight loss method. The sample is dried in a 105 ± 2 ℃ oven under normal pressure until constant weight, and the lost weight is moisture. By calculating the weight difference of the sample before and after drying, the moisture content or volatile matter content at 105 ℃ can be calculated, which can be divided into two methods: atmospheric pressure drying and vacuum drying, with the same principle.

Calculation formula: (weight before drying - weight after drying) ÷ weight before drying × 100=moisture content (%)

Calculation formula: (W1-W2)/(W1-W0) × 100=moisture content (%)

In the formula: W1=weight of the sample and weighing vessel before drying at 105 ℃ (g);

W2=weight of the sample and weighing vessel after drying at 105 ℃ (g);

W0=weight of the constant weight weighing vessel (g).

Attention: The constant temperature incubator is kept within the specified temperature, and the constant weight aluminum box is called constant weight until the difference between the two weights is less than 0.005 grams. After sampling, it is dried according to the requirements until the difference between the two weights is less than 0.005 grams. However, the allowable difference between the two measurements is not more than 0.2%.