Mcr 301

The rheological properties of FIB-OPEs and SPH-OPEs were performed by an MCR301 rheometer (Anton Paar Co., Ltd., Graz, Austria) in the rotational rheological test mode. The appropriate amount of emulsion samples was added onto the platform using a plastic tip dropper, and the interval between the rotor (PP50) and the platform was set to 1.00 mm. The apparent viscosity of the emulsion samples was measured at 25 ± 0.1 °C with the change of shear rate (0.1–10 s⁻¹), and the measurement interval was 2 s. The linear viscoelastic regions of the emulsion samples were obtained using the dynamic strain sweep test at a fixed frequency of 1 Hz at 25 ± 0.1 °C. The frequency sweeps were performed from 1 to 20 Hz, and the storage modulus (G′) and loss modulus (G″) of FIB-OPEs and SPH-OPEs were, respectively, measured at a fixed strain of 0.1%.

Temperature sweeps were performed to explore the melting process of the studied ice cream samples by increasing the temperature from -20 to 10 °C. Measurements were performed using a rheometer (MCR 301, Anton Paar, Germany) at a constant strain of 0.005% and a frequency of 1.6 Hz with a plate-plate geometry (PP50/P2). A moveable hood covering the plate-plate geometry was connected to the cooling system to control the temperature. An air pump was also connected to the hood to prevent heat exchange with the environment. Prior to the measurement, the initial temperature of the plate was reduced to -20 °C using a Peltier element, and then the temperature was increased to 10 °C with a heating rate of 0.5 °C/min. Sixty measuring points were recorded and the total measuring time was 60 min. Storage modulus (G') and loss modulus (G") were measured. Three zones could be identified during the whole process (Wildmoser et al., 2004 ) and two parameters were extracted after the measurements: (1) the mean value of G' in the frozen state (zone I, G'ZI), and (2) the slope of G' during the melting stage (zone II, SZII), which is an indicator for the speed of melting (Eisner et al., 2005 ). Ice cream samples were measured at least twice to obtain average values.

We used the Anton Paar rotary rheometer (MCR301, Graz, Austria), equipped with a flat plate geometry system (Model CP50), with a plate spacing of 0.5 mm. An appropriate amount of emulsion sample was placed in the center of the rheometer plate and excess samples around the plate were removed to avoid the effect of edge-effect. In order to avoid sample water loss during the test, the conical plate was sealed using silicone oil.
First, the emulsion was scanned at the rate of 0.01–100 s⁻¹, and the viscosity and shear stress of the sample were recorded. Secondly, the elastic modulus (G′) and viscous modulus (G″) were measured while conducting a strain sweep between 0.01% and 100% strain, at 1 Hz and 25 °C, to determine the linear viscoelastic region. Then, in the linear viscoelastic region, 0.5% strain was selected and a frequency sweep of 1–100 Hz was performed to record the elastic modulus (G′) and viscoelastic modulus (G″) of the emulsion. The last experimental content was a temperature scan. In the linear viscoelastic region, 0.5% strain and 1 Hz were selected, the scan temperature range was 4~80 °C, the heating rate was 4 °C·min⁻¹, and the compound viscosity of the emulsion during the heating and holding process was recorded.

Monitoring the rheological behavior of samples using an oscillatory rheometer (MCR 301, Anton Paar, Graz, Austria) with a parallel plate (PP50, diameter = 50 mm) and 1.0 mm gap. Low-density silicone oil was used to the edge of the parallel plate to prevent the evaporation of the liquid.

The dynamic-mechanical properties of cured samples with dimensions of 10 mm × 4 mm × 50 mm were investigated by DMTA measurements in torsion mode using an Anton Paar MCR 301 apparatus (Anton Paar GmbH, Buchs, Switzerland) operating at frequency f = 1 Hz over a temperature range between 25 °C and 300 °C at a heating rate of 2 °C/min. The position of tan δ at its maximum was taken as the glass transition temperature.

The rheological properties of the scaffolds were determined using an Anton-Paar MCR301 constant stress rheometer with a 15 mm parallel-plate geometry (lower glass plate) and a gap of 240 mm. An evaporation blocker stage was used along the experiments to avoid sample dehydration. Firstly, oscillatory strain sweep measurements were performed to obtain the linear viscoelastic region (LVR) using a deformation range from 0.1 to 100% at a frequency (ω) of 6.28 rad/s (1 Hz) and 37°C. The LVR region is defined as the deformation range where the elastic modulus (G′) is independent of the applied deformation (%γ). Once the LVR was determined, changes in the mechanical properties as a function of time were monitored for a set of scaffolds by means of amplitude (0.1–100% at 10 rad/s) and frequency sweep experiments (0.1–100 rad/s at a constant strain of 0.1%) within the LVR at 37°C.