## 4 Conclusions  
The results of this study show that HPP prior to heat treatment is an effective method for producing high-quality pangasius gels at reduced salt conditions. HPP improved gel texture, whiteness, and water-holding capacity in pangasius gels with 2% salt while maintaining these properties of gels with 1% salt comparable to heat-induced gels (HIGs) with 2% salt. SDS-PAGE results showed that increasing pressure reduced the intensity of high molecular weight proteins in both SDS-soluble and sarcoplasmic proteins, likely due to pressure-induced aggregation. Additionally, actin from sarcoplasmic proteins was undetectable in all treatments, indicating that the effect of thermal treatment is predominant over-pressure treatment on sarcoplasmic actin protein.  
HPP also facilitated the formation of a more compact gel network, as confirmed by SEM analyses. FTIR spectra showed that HPP increased \(\alpha\)-helix content, stabilizing intramolecular hydrogen bonds and reducing protein unfolding. At 1% salt, PG had lower random structure content than HIGs, suggesting reduced protein denaturation. These structural modifications contributed to enhanced gel strength and stability, even at a lower salt concentration (1%). These results indicate that HPP can be applied to develop salt-reduced pangasius gel products with improved textural and structural properties. This approach can satisfy the growing consumer demand for healthier, lower-sodium foods and may contribute to improved product quality and greater acceptability in commercial applications. However, this study has some limitations, as it was conducted using a single fish species (pangasius) under fixed HPP conditions, including temperature and holding time. Therefore, more studies are needed to examine the changes in pangasius gels under different HPP conditions. Future research should explore the long-term storage stability and sensory attributes of high-pressure-induced pangasius gels to further validate their commercial viability. In addition, the investigation of the molecular mechanisms of protein interactions, including bond formation such as disulfide, hydrophobic, and hydrogen bonds, should be conducted for a deeper understanding of the structural changes induced by HPP and their impact on gelation behavior and functional properties.  
Conceptualization, B.Q.T. and V.C.H.; methodology, B.Q.T., R.B. and T.N.A.H.; software, B.Q.T., K.N.H.N., L.T.N. and T.N.A.H. validation, B.Q.T., R.B., K.N.H.N., L.T.N., T.N.A.H. and V.C.H.; formal analysis, B.Q.T., T.N.A.H. and V.C.H.; investigation, B.Q.T., K.N.H.N., T.N.A.H. and V.C.H.; resources, B.Q.T. and R.B.; data curation, B.Q.T., K.N.H.N. and V.C.H.; writing--original draft preparation, B.Q.T. and V.C.H.; writing--review and editing, R.B. and V.C.H.; visualization, B.Q.T. and V.C.H.; supervision, R.B. and V.C.H.; project administration, B.Q.T. and V.C.H.; funding acquisition, B.Q.T. and R.B. All authors have read and agreed to the published version of the manuscript.  
**Funding:** This research was funded by the Vietnam Ministry of Education and Training under the project titled 'Research on high-pressure processing technology applied to pangasius (_Pangasianodon hypophilulans_) muscle and its application in developing value-added products', grant No. B2023-NLS-02.  
**Informed Consent Statement:** Not applicable.  
**Data Availability Statement:** The original contributions presented in the study are included in the article, further inquiries can be directed to the corresponding author.  
**Acknowledgments:** The corresponding author acknowledges support from Ho Chi Minh City University of Technology and Education (HCMUTE), Vietnam.  
**Conflicts of Interest:** The authors declare no conflicts of interest.