4.2.2. Accelerated Evaluations

#### Cycling Test

The cycling test was performed according to the method reported by Almeida and Bahia [43] with slight modifications. Hydrogels samples, obtained immediately after HPP treatments (day 0), were stored in a climatic chamber (TCN-50 plus, ARGO Lab, China) and the temperature was changed between 4 and 40 ◦C every 24 h for 7 days. Before undergoing TPA, all samples were stored at 20 ◦C for 24 h.

## Rheological Analysis

The rheological analysis of samples was carried out in a controlled stress rheometer (AR2000-TA instruments, New Castle, DE, USA) in a plate–cone geometry configuration (40 mm diameter, 2◦ ) with a gap of 52 µm. The viscoelastic responses of hydrogel samples were recorded (immediately obtained after HPP treatments), namely the elastic (G0 ) and viscous (G00) moduli under different stress (0.01 to 1000 Pa at 25 ◦C) and temperature (25 ◦C to 80 ◦C at 1◦C/min) conditions. Additionally, for the sake of comparison, the same measurements were also carried out on commercial hydrogel samples (Diclac®, Eurofarma, Chile) and thermal gels. The latter were produced according to the method and processing conditions described by Larrea-Wachtendorff et al. [13].

#### *4.3. Statistical Analysis*

The results were analyzed using statistical descriptive analysis (mean ± SD), one-way ANOVA, and post-hoc comparison using the Fisher least significant difference (LSD) test to determine significant differences among experiments (*p*-value was <0.05). All analyses were performed using Statgraphic Centurion XVI Statistical Software (Statistical Graphics Corp., Herdon, VA, USA).

**Author Contributions:** Conceptualization, D.L.-W. and G.F.; methodology, D.L.-W.; software, D.L.-W.; validation, D.L.-W., V.D.G. and G.F.; formal analysis, D.L.-W. and G.F.; investigation, D.L.-W. and V.D.G.; resources, G.F.; data curation, D.L.-W.; writing—original draft preparation, D.L-W.; writing review and editing, D.L.-W., V.D.G. and G.F.; visualization, D.L.-W. and G.F.; supervision, G.F.; project administration, G.F.; funding acquisition, G.F. All authors have read and agreed to the published version of the manuscript.

**Funding:** This work was financially supported by ProdAl Scarl and the University of Salerno, Italy.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** The data presented in this study are available in the article.

**Conflicts of Interest:** The authors declare no conflict of interest.

#### **References**

