*2.4. Statistical Analysis*

Minitab17 (Minitab Inc., State College, PA, USA) was used for the statistical analysis of all results, reported as mean ± standard deviation (SD) of two replications. To evaluate

the differences between samples, one-way ANOVA was applied. The Fisher LSD test was employed for the post-hoc comparisons of the means. Correlation between variables was determined by Pearson's correlation coefficient test. Statistical significance was set at *p* < 0.05 level.

### **3. Results and Discussion**

### *3.1. Evaluation of the Pre-Treatments*

3.1.1. Total Phenolic and Antioxidant Activity

Table 2 reports the mean values, standard deviation, and results of the statistical analysis of the total phenolic contents and the antioxidant activity measured in the vine shoot extracts subjected to the different investigated treatments. Several studies have shown that vine shoots are rich in phenolic compounds [45–49]. Concerning the vine shoots of the Primitivo variety, the results showed that the extracts, irrespective of the pre-treatments, contained similar amounts of TPC, except for vine shoots treated at 50 ◦C for 24 h, in which a significant reduction was observed (18.4 ± 0.1 mg g<sup>−</sup><sup>1</sup> DW). Instead, in regards the vine shoot extracts of the Negroamaro variety, except for the treatment at 80 ◦C for 10 min, the other two applied heat treatments reduced the TPC. In particular, the treatment at 70 ◦C for 15 min reduced TPC by 11.3% with respect to the untreated vine shoots, which had the highest content (21.2 ± 0.1 vs. 23.9 ± 0.1 mg g<sup>−</sup><sup>1</sup> DW, respectively).

**Table 2.** The TPC (total phenolic content), DPPH (antioxidant activity determined by the DPPH assay), and ABTS (antioxidant activity determined by the ABTS assay) of the vine shoot extracts from the Primitivo and Negroamaro varieties. Results are expressed as mean ± standard deviation (*n* = 2); different letters for each variety in the same column indicate a significant difference according to the Fisher test (*p* < 0.05).

