**4. Conclusions**

In this work, CS-TPP encapsulated CBLO nanoparticles (CS@CBLO NPs) were successfully fabricated using a two-step method via emulsification and ionic gelation. The particle size and its structure were revealed to be 347 nm and 174–456 nm, respectively, by scanning electron microscopy (SEM) and dynamic light scattering (DLS). The loading capacity (LC) and encapsulation efficiency (EE) of CBLO in CS@CBLO NPs were determined according to the TGA/DTG result at the degradation temperature of 368 ◦C. The LC and EE values were shown to be about 17.77~33.43% and 25.93~50.27%, respectively, when the ratio of CBLO to chitosan was in the range of 0.25–1.25. The oxidative stability of CS@CBLO NPs evaluated by FTIR showed that the CS@CBLO NPs could effectively prevent CBLO oxidation. The results demonstrated that the strategy of encapsulation using chitosan can effectively protect high-sensitivity materials from metamorphism. The CS@CBLO NPs combined two healthy ingredients, chitosan and fish oil, a kind of nano powdered fish oil; it can be conveniently used in various foods as a fortification of DHA and EPA to enhance their usage in the food and pharmaceutical industries.

**Author Contributions:** Conceptualization, C.-H.K.; methodology, P.-K.C.; formal analysis, P.-K.C., C.-Y.H. and C.-L.L.; investigation, P.-K.C. and M.-F.T.; resources, C.-Y.H., C.-L.L., C.L. and C.-J.S.; data curation, M.-F.T.; writing—original draft preparation, M.-F.T. and C.-H.K.; writing—review and editing, C.-H.K.; supervision, C.-H.K. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was funded by the Ministry of Science and Technology of Taiwan, grant number MOST 110-2221-E-992-009-.

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

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Data is contained within the article.

**Acknowledgments:** We are grateful to Center for Aquatic Products Inspection Service, NKUST, for providing analysis of fatty acid composition of CBLO.

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

### **References**

