Measurement of viscoelasticity distribution between the surface and center of cooked noodles using the modified compression creep test

Abstract

To characterize the koshi, or physical texture of cooked noodles, the distribution of viscoelasticity between the surface andcenter of cookednood les was investigatedusing a modifiedcompression creep test. Typical creep curves were described at 4 different points between the surface and center of the cooked noodles, and individual points of sample A (shortly after cooking) andsample B (24 hours after cooking) were analyzedfor 6 or 8 viscoelastic elements. The measured η1, η2 and η3 were 1/10∼1/100 smaller than ηN; therefore, we ignored the effects of these 3 viscous elements and simplified the noodle viscoelasticity into 2 elements. The calculated relaxation time at the measured points of the cooked nood les ranged from 10 seconds to about 1 minute, which was much longer than the less than 1 second noted for chewy cooked nood les. As a result, it was proposed that the elastic elements significantly affected the chewiness of the cooked nood les. The elasticity of sample A increased gradually from the surface to the center of the noodle, which show edelevated chewiness, i.e., strong koshi. The elasticity of sample B increased shortly after chewing and then leveled out or decreased, indicating that the noodle had lost springiness. These results agreedwith those from sensory evaluation. Copyright © 2014, Japanese Society for Food Science and Technology.