1. Basic principle of hot air drying of non-fried instant noodles production line equipment
Hot air drying is the drying method for producing non-fried instant noodles. Since instant noodles have been steamed at a high temperature of 95~100℃, most of the starch contained in them has been gelatinized, the gluten composed of protein has been denatured and solidified, and the organizational structure has been basically fixed. Different from the internal structure of noodles without steaming, the noodles can be dried in a relatively short time at a higher temperature and lower humidity.The water in the steamed back strip mainly exists in the form of chemical bound water, physical and chemical bound water and mechanical bound water. The latter two kinds of water are easy to remove under general heating conditions, while the chemical bound water is difficult to remove under general conditions. Hot air with low relative humidity is used to circulate through the surface block repeatedly. Because the partial pressure of water vapor on the surface of the surface block is greater than that of water vapor in the hot air, the amount of water evaporation on the surface block is greater than the adsorption amount, so the water inside the surface block escapes. The moisture evaporating from the surface block is taken away by the drying medium and finally reaches the specified moisture.
2. Process requirements for hot air drying of non-fried instant noodles production line equipment
The product shall be less than the moisture specified in the product quality standard, so as to facilitate the preservation, packaging, transportation and sales. The shape of the surface block shall be consistent as far as possible, the drying speed shall be increased as far as possible, and the αization state shall be fixed quickly. In order to prevent instant noodles in the preservation, transportation of a starch back to β starch, to ensure that the noodles have a good degree of rehydration. To achieve these, the temperature of the drying medium should be as high as possible, and the drying time should be as short as possible. The moisture content of the dried instant noodles should be below 12. 0%.