**4. Conclusions**

Vine shoots are a rich source of bioactive compounds, with Rsv and Vf stilbenes characterised as the most important. The amounts of these stilbenes in the vine shoots could be strongly affected by both extrinsic and intrinsic factors. Our results showed that the heat pre-treatment of the plant material had a negligible effect on the concentration of TPC, Rsv, and Vf. On the other hand, the genotype had a strong influence on Rsv and Vf accumulation. The results of this work confirmed the possibility of obtaining extracts particularly rich in Rsv from Italian vine shoots, assigning an important economic value to a waste product with zero cost.

Thanks to its many applications, resveratrol has grea<sup>t</sup> potential in the future market. A recent report shows that the global resveratrol market will reach USD 99.4 million by the end of 2026 [56]. However, its price also depends on the costs of the raw materials and the entire extraction process. Considering this last point, the outcomes of this work impart useful insights proving that there is no need to consume energy for vine shoot pretreatment, decreasing the general costs. However, more studies are needed to confirm these observations and to investigate the concentration of Rsv and other stilbene compounds in the same vine shoot varieties from different geographical areas or in other Italian varieties.

**Supplementary Materials:** The following supporting information can be downloaded at: https:// www.mdpi.com/article/10.3390/foods11040553/s1, Figure S1: Stilbenes HPLC-DAD chromatogram of cultivar Palieri vine-shoots extract detected at 306 nm (a) and 324 nm (b); Table S1: Stilbene concentrations (mg kg−<sup>1</sup> DW) in vine-shoots from 23 different Italian varieties. Means and standard deviation (*n* = 2) are represented in the same column and data followed by different letters indicate statistically significant differences according to Fisher's LSD test (*p* < 0.05). For sample codes see Table 1 of the main text.

**Author Contributions:** Conceptualization, M.N., A.F.C. and F.C.; methodology, M.N. and A.F.C.; software, V.M.P.; formal analysis, M.N. and A.F.C.; writing—original draft preparation, M.N., A.F.C. and F.C.; writing—review and editing, M.N., A.F.C., G.S., V.M.P., G.G. and F.C.; supervision, F.C.; funding acquisition, F.C. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was funded by the Ministero dell'Istruzione, dell'Università e della Ricercaprogrammi di ricerca 2017 (2017JTNK78) and "GOOD-BY-WASTE. Obtain GOOD products—exploit BY-products—reduce WASTE" (CUP H98D19000940006).

**Data Availability Statement:** Not applicable.

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