In this study, the effect of steam treatment (pre-cooking) on the drying rate of a noodle sheet during the manufacture of instant noodles was examined. The noodle sheet was dried using a forced convection dryer with an air velocity of 2.5m/s. Air temperatures ranging 80～110℃ were set as the drying conditions. Since measured values of relative humidity of air used for the drying tests were 1% or less, we described the relative humidity with 0%. The noodle sheet subjected to steam treatment dried faster than a noodle sheet not subjected to steam treatment when the drying temperature was same. The drying contraction of the noodle sheet subjected to steam treatment was less than that of the noodle sheet not subjected to steam treatment. The steam-treated noodle sheet dried faster than the untreated noodle sheet because the decrease in the evaporation area of water was small on the steam-treated noodle sheet. As a result of evaluating the relationship between quality (good quality implied a noodle sheet without foaming) and the drying rate of a noodle sheet, it was found that drying at 100℃ was suitable for steam-treated noodle sheets. Moreover, drying at 90℃ was suitable for noodle sheets that are not steam-treated.
