**4. Conclusions**

The results of the present study showed that the same trends and similar particle size values were obtained by microscopy-assisted digital image analysis and laser diffraction particle size analysis for the determination of particle size in emulsions. Considering the installation costs of devices for measuring laser diffraction, microscopy-assisted digital image analysis seems to be a very useful and effective alternative. On the other hand, if sample characterization is to be performed, it should be noted that there are certain differences in the measured values, and slightly larger droplet sizes are calculated with

the microscopy-assisted digital image analysis technique. In addition, while the results can be obtained in about 5 min when taking measurements with laser diffraction devices (total time for analysis), the analysis and calculation process may take one or several days per sample with the procedure developed in the present study, unless working with highcapacity workstations. It was observed that comparable results were obtained for D(90), D[3,2], and D[4,3], which were correlated with the physical properties of the emulsions.

In summary, the microscopy-assisted digital image analysis procedure developed in this study can provide very reasonable results when it is impossible to obtain/use laser diffraction particle size analyzers. However, it should be noted that performing this method is labor- and time-intensive.

**Author Contributions:** P.S.: formal analysis, validation, investigation, data curation, and writing original draft. O.G.: conceptualization, methodology, and data curation. L.Y.A.: writing—review and editing and supervision. Z.E.: conceptualization, methodology, writing—original draft, and project administration. All authors have read and agreed to the published version of the manuscript.

**Funding:** This work was supported by the Scientific and Technological Research Council of Turkey (TUBITAK) (Grant No. 120O763). The authors are also grateful to Croda for providing the emulsifiers.

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

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Not applicable.

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