**4. Conclusions**

This study investigated a process that uses the SLE method on Pinot noir pomace, which was optimized to extract as many of the three flavonoids (**1**, **2** and **3**) as possible and a method that derivatizes the polyphenolics in the extract, converting them into fatty acyl derivatives. It was hoped that this process would result in products that could display some improved health-promoting properties. Unfortunately, this process did not achieve the expected outcome; however, the findings from these investigations remained interesting. In the small-scale extraction study, the trial of 28 selected solvent systems, led to identification of the most effective solvent system for each individual flavonoid and the identification of 6 systems that were ideal for extracting all three flavonoids. Implementing one of these solvent systems for the SLE of large-scale mass of pomace, interestingly, led to significantly reduced quantities of the flavonoids compared to those observed in the small-scale study. Despite that, this extract was taken into the next derivatization step. The IR spectra of these products was used to indicate the success of this derivatization. The subjection of these products to antiproliferative testing did not display improved results. The exploration of the limitations to these methods and suggested improvements may serve as foundations for future work with possibilities to increase success.

**Supplementary Materials:** The following are available online at https://www.mdpi.com/article/10 .3390/foods11141999/s1. Table S1: the HPLC method, Table S2: flavonoid quantities extracted using different solvent systems, Figure S1: IR spectra of the non-derivatized and derivatized products.

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

**Funding:** This work was financially supported by Marlborough Research Centre for the purpose of "extracting value from grape marc".

**Institutional Review Board Statement:** Not Applicable. **Informed Consent Statement:** Not Applicable.

**Data Availability Statement:** Not applicable.

**Acknowledgments:** The authors wish to thank the University of Auckland for providing the Doctoral Scholarship and Euphemia Leung for conducting the antiproliferative studies on the derivatized products.

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