The raw and cooked noodles were cut transversally into cubes, immediately
frozen at −80 °C and lyophilized. Freeze-dried samples
were mounted on a silver specimen holder and coated with gold for
60 s. Microstructure of cross-section was observed by a Scanning
Electron Microscope (HITACHI, Japan) at a voltage of 15.0 kV with micrographs
taken at magnification of 600×.