Zhengzhou Dongfang Naomu Food Machinery Co., Ltd. has been specialized in the production of flour products machinery for 50 years. The basic processing steps for machine-made noodles involve mixing raw materials, resting the crumbly dough, sheeting the dough into two dough sheets, compounding the two sheets into one, gradually sheeting the dough sheet into a specified thickness and slitting into noodle strands. Noodle strands are further processed according to noodle types.

Mixing Ingredients

Mixing formula ingredients is often carried out in a horizontal or vertical mixer for 10-15 minutes. Since the horizontal mixer seems to have better mixing results, it is more commonly used than the vertical one in commercial noodle production. Mixing results in the formation of a crumbly dough with small and uniform particle sizes. Since the water addition level is relatively low (vs. bread doughs), gluten development in noodle dough during mixing is minimized. This improves the dough sheetability, sheeted dough smoothness and uniformity. Limited water absorption also slows down noodle discoloration and reduces the amount of water to be taken out during the final drying or frying processes.

Flour proteins, pentosans and starch (especially damaged starch) determine the flour water absorption level. Even so, the water absorption level in noodle dough is not so sensitive to processing as is that in bread dough. Variations in noodle dough water absorption among different flours is generally within 2-3%, and this is usually determined by dough handling properties. Flour particle sizes and their distribution affect the time water penetrates into the flour. Large particle flours require a longer time for water to incorporate and tend to form larger dough lumps. It is desirable to have relatively fine and evenly distributed particle size flours to achieve optimum dough mixing.

Dough Resting

After mixing, the dough pieces are rested for 20-40 minutes before compounding. Dough resting helps water penetrate into dough particles evenly, resulting in a smoother and less streaky dough after sheeting. In commercial production, the dough is rested in a receiving container while being stirred slowly.

Sheeting and Compounding

The rested, crumbly dough pieces are divided into two portions, each passing through a pair of sheeting rolls to form a noodle dough sheet. The two sheets are then combined (compounded) and passed through a second set of sheeting rolls to form a single sheet. The roll gap is adjusted so that the dough thickness reduction is between 20-40%. The combined dough sheet is often carried on a multi-layer conveyor belt located in a temperature and relative humidity controlled cabinet. This step is to relax the dough for easy reduction in the subsequent sheeting operation. The resting time takes about 30-40 minutes.

Sheeting, Slitting and Waving

Further dough sheeting is done on a series of 4-6 pairs of rolls with decreasing roll gaps. At this stage, roll diameter, sheeting speed and reduction ratio should be considered to obtain an optimum dough reduction. Noodle slitting is done by a cutting machine, which is equipped with a pair of calibration rolls, a slitter, and a cutter or a waver. The final dough sheet thickness is set on the calibration rolls according to noodle type and measured using a thickness dial gauge. Noodle width determines the size of noodle slitter to be used (noodle width, mm = 30/slitter number). The sheet is cut into noodle strands of desired width with a slitter. Noodles can be either square or round in shape by using various slitters. Noodle strands are cut into a desirable length by a cutter. At this stage, Chinese raw noodle, Japanese udon noodle, chuka-men and Thailand bamee noodle making is complete. For making instant noodles, noodle strands are waved before steaming and cutting.