Changes in the rheological characteristics of the gelatin
solutions were measured using a Carri-Med CSL2500 controlled
stress rheometer ~TA Instruments, New Castle, DE!
having a fixed bottom plate, with a Peltier plate for temperature
control and a 6-cm-diam flat-plate acrylic plate fixture.
The Peltier plate of the rheometer was heated to 35 °C and
0.4 mL of gelatin solution, at 60 °C, was loaded onto the
plate. The gap between the Peltier plate and the fixture was
closed to 60 mm, and 0.1 mL of light mineral oil was applied
to the circumference of the sample to prevent evaporation of
water and the formation of gelatin bridges between the
plates. The temperature was then quenched to the desired
gelation temperature. Frequency sweeps were conducted at a
torque of 70 mNm.