The chemical characteristics, phenolic content and antioxidant activity of olive oils flavored with garlic, lemon, oregano, hot pepper, and rosemary were evaluated during 9 months of storage. At the end of the storage period, the unflavored and the garlic-flavored oils maintained their chemical parameters within the limits fixed for extra-virgin olive oils. After 9 months of storage, a noticeable decrease in phenolic content was observed in all the oils. The highest (35.0 ± 3.9 mg/kg oil) and the lowest (6.3 ± 0.4 mg/kg) phenolic contents were detected in the unflavored and garlic-flavored oils, respectively. Compounds such as 3,4-DHPEA-EDA (3,4-dihydroxyphenylethyl 4-formyl-3-formylmethyl-4-hexenoate, the dialdehydic form of decarboxymethyl elenolic acid linked to hydroxytyrosol) and p-HPEA-EDA (dialdehydic form of the decarboxymethyl elenolic acid linked to tyrosol) were the most abundant in both unflavored and lemon-flavored oils up till 6 months of storage. At the end of the storage period, increases in 3,4-DHPEA (hydroxytyrosol) and p-HPEA (tyrosol) were measured in almost all the oils. During storage, the antioxidant activity coefficients of the phenolic extracts, calculated according to the b-carotene bleaching assay, significantly decreased and, after 9 months, were in a decreasing order: rosemary (51.3 ± 4.2), hot pepper, lemon, oregano, unflavored, and garlic (8.5 ± 0.7).

Seven table grape cultivars grown in Apulia region were considered: Italia, Baresana, Pizzutello, Red Globe, Michele Palieri, Crimson Seedless, and Thompson Seedless. Seeds, skins and pulps were extracted and analyzed for their phenolic profiles and antioxidant activities. The hierarchy in the phenolic contents was seeds, skins, and pulps. These results indicate that the intake of the whole berries (seeds included) must be strongly recommended. The highest phenolic contents were detected on Italia and Michele Palieri cv., respectively within the white and the red/black table grapes. Seeds gave a high contribution to the berry antioxidant activity, as they had higher phenolic content than skins and contained high quantities of proanthocyanidines, but the strongest antioxidant activity was shown by the pulp juices due to their content in hydroxycinnamyl acids. The principal component analysis applied to the phenolic composition and antioxidant activity of skins, pulps, and seeds allowed a good separation of Italia and Michele Palieri cultivars. According to the cluster analysis, cultivars were grouped into two clusters, one including Michele Palieri and the other one including Italia, Baresana, Pizzutello, and Thompson Seedless.

Phenolic composition and antioxidant activity of extra-virgin olive oils extracted from several Italian varieties were studied at production and during storage. The antioxidant activity was measured according to the following tests: in the aqueous phase, by radical scavenging of the 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical cation; and in the lipid phase, using the beta-carotene bleaching method. The phenolic content was not correlated to the oxidation indices (peroxide value and spectrophotometric constants). The phenolic contents and profiles of the various cultivars showed remarkable differences. The phenolic content was strongly correlated with the antioxidant activity measured according to the beta-carotene test and weakly correlated with the radical scavenging ability.

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The aim of this study was to assess the influence of 9 winemaking technologies (traditional, delestage, saignée, delayed punching-down, addition of grape seed tannins, addition of ellagic-skin-seed tannins, heating of must-wine, cryo-maceration, and prolonged maceration) on the phenolic content and antioxidant activity of Primitivo musts and wines. Three methods for the determination of the antioxidant activity were compared: DPPH, beta-carotene bleaching assay, and ABTS. Oenological parameters and composition of the phenolic fraction of 1-y-aged wines was also determined. The addition of tannins allowed the increase of the phenolic content of musts and wines in a greater amount than the other technologies. The results concerning the antioxidant activity depended on the method applied. Concerning musts, the DPPH assay did not highlight great differences among technologies, whereas the addition of tannins allowed the obtainment of the highest antioxidant activity according to beta-carotene and ABTS assays. The wine aging determined an increase of the antioxidant activity, independently on the method applied. Wine obtained through traditional technology, saignée, and addition of tannins showed the highest antioxidant activities according to DPPH and beta-carotene. The highest correlation coefficients (0.961 and 0.932) were calculated between phenolic content and ABTS values of musts whereas the lowest values (0.413 and 0.517) were calculated between phenolic content and ABTS values of wines. Wines produced through traditional technology were the richest in anthocyanins. The addition of tannins allowed to obtain high content in monomeric anthocyanins, flavonoids, flavans reactive to vanillin, and coumaroylated malvidin and a low content in acetylated malvidin. Practical Applications: It is well known that a moderate consumption (equivalent to 2 glasses per day) of red wine is actually recommended since it appears associated with a decreased incidence of cardiovascular diseases. The mechanisms involved in this protective effect are not completely understood although they appear related to the presence of phenolic compounds. To increase the intake of these compounds without increase of the wine consumption, it is necessary to improve their extraction during maceration. This study could represent a helpful tool for wineries aimed to know the way to increase the antioxidant content of their wines, thus changing them in functional beverages and prolonging their shelf life.