2.9. Texture profile analysis (TPA)
The cooked noodles were kept in a covered Petri dish
and texture analysis was carried out within 15 min using
Texture analyzer (TA-XT2, Texture technologies Corp,
USA).
Texture profile analysis (TPA) was conducted as
described by Bhattacharya et al. (1999). A strand of
cooked noodle with 1.0mm thickness was compressed by a
cylinder probe (35.0mm diameter) until the deformation
reached 75% at a speed of 1.0 mm/s. The pause between
the first and second compressions was 0.5 s. From the
force–time curve of the texture profile, textural parameters
including hardness, adhesiveness and chewiness were
obtained. Ten measurements were made for each sample.
For testing tensile strength, a strand of cooked noodle
was wound two or three times around parallel rollers of
texture analyzer. The upper arm was set to travel apart
from the lower arm at a speed of 3.0 mm/s. The maximum
force (g) required to break the noodle strand gave an
indication of the sample resistance to the breakdown and
the distance (mm) in which the strand started to break
indicated the extensibility. The measurements were
repeated 10 times for each sample.