## 3 Results and Discussion
### Identification and Quantification of Polyphenols in Cranberry Wine  
Qualification and quantification of the anthocyanins were carried out using HPLC according to Section 2.5. Qualification of phenolic acids, flavonoids, and proanthocyanins was undertaken on LC-MS/MS by comparing the retention times, along with MS and MS/MS data, with available standards. A list of the identified compounds is presented in Table S1. The concentration of the polyphenols in nine cranberry wines is presented in Table 2. Four compounds (\(m\)-salicylic acid, vanillic acid, trans-sinapic acid and kaempfer) were present in trace amounts in the wine samples, and their contents were not quantified (Table 2). Overall, results show that ANC, PAC, flavonol and phenolic acids were the major classes of phenolics present in the cranberry wine samples. Among the four classes identified, anthocyanins accounted for the largest proportion (28% to 47%), while the other classes made up lower proportions: proanthocyanins (11% to 30%), phenolic acids (17% to 23%), and flavonoids (20 to 34%). The results of total ANC from the HPLC analysis of the wines (Table 2A) were in agreement with the spectrophotometric measurement method, where [PERSON] had the highest levels among the three cultivars. Comparing the viinification method, thermovinification had a better advantage than the White and Red approaches, revealing that heat treatment at 70 \({}^{\circ}\)C increased the ANC extraction from pomace. The ANC content is the compositive result of extraction, thermal and enzyme degradation. From the literature, high temperatures were applied regularly to advance extraction efficiency as it improves solvent penetration, compound diffusion, and solubility [37; 38; 39]. Furthermore, heat treatment could also enhance anthocyanin extraction by inhibiting enzymatic oxidation. Nonetheless, anthocyanins have been reported as being heat-sensitive, and a high temperature could cause their degradation [39]. Thus, there is an ideal temperature expected for different plant matrices, depending on their anthocyanin composition. The previous study on blueberry anthocyanins indicated that a temperature higher than 80 \({}^{\circ}\)C could affect stability [40]. Our current study results revealed that 70 \({}^{\circ}\)C was a suitable temperature for producing cranberry wine to give high ANC, as it enhanced extraction without adversely affecting the ANC composition (compared to cranberry juice, unpublished data). Among the six anthocyanins determined, cynidin-3-arabinoside present at the highest amount (44.9% to 72.2%), while cynidin-3-glucoside occupied the smallest proportion (1.2% to 3.2%), similar to the cranberry anthocyanin composition in the literature [29]. Results of total PAC obtained from LC-MS/MS (10.3 to 37.0 mg/L) (Table 2B) were much lower than those from the DMAC method (129 to 293 mg PAC A2 equivalent/L) (Figure 1). This dissimilarity is caused by that the profiling of proanthocyanins by LC-MS/MS only included monomers and dimers owing to the available commercial standards, which consisted only a small portion of total PACs. As reported in other studies, PACs present mainly as polymers in cranberries, with an average polymerization of 15 flavonoid units [4]. Considering cultivar effects, total PAC (25.1 to 37.0 mg/L) and all factions in PAC showed the highest amount in the Bergman samples, while the Pilgrim samples contained the lowest PAC (10.3 to 13.8 mg/L), in agreement with the DMAC method (Figure 1). The highest PAC appeared in the BW sample (37.0 mg/L), 3.6 times greater than that in the PT sample (10.3 mg/L). The PAC results of wines share a similar pattern with juices among cultivars (Table 1), indicating cultivar difference as a potential reason for this diversity. In contrast, different treatments did not give significant difference in PAC (\(p>0.05\)). Of PAC monomers and dimers, epicatechin accounted for the highest amount (39.6% to 46.5%), and the proportion of epicatechin is similar among all samples.