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UNLABELLED Quality indices, antioxidant compounds, and antioxidant activities of extra-virgin oils from Coratina olives were evaluated during a 12-mo storage. Whole and stoned olives, picked at 2 different maturation index (MI), were submitted to malaxation for 45 min and extracted by a 3-phase continuous system. A 90-min malaxation trial was also performed for the stoned olives. The following parameters were monitored: free acidity, peroxide value, K(232) and K(270) indices, sensory profile, total phenolic content (TPC), phenolic profiles, tocopherol compounds, and antioxidant activity (AA). The highest TPC, AA, and sensory score were found for the oils obtained by olives picked at low MI and by stoned olives. After 12 mo, all the oils were still included into the "extra-virgin" category, and those deriving from whole olives picked at the lowest MI showed the best sensory characteristics due to high fruity and well-balanced pungent and bitter tastes. PRACTICAL APPLICATION This study could represent a helpful tool for oil-makers to improve the marketing of extra-virgin olive oils produced from cultivars with very high phenolic contents, such as Coratina, generally not adequately appreciated by consumers because of their excessive bitterness and pungent taste. These oils, when extracted from whole olives, are generally consumed after a certain period of time (at least 6 mo) during which a decrease in the phenolic content occurs. The results of the present work demonstrate that oils extracted from olives picked at low maturation index can be marketed immediately after production if subjected to stoning and malaxed for a short time. This procedure allows to adjust the phenolic content and to obtain a high flavor and a well-balanced taste.

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.

A study on the influence of the type of container and storage temperature on ascorbic acid degradation and browning in a model system simulating a citrus juice is presented. The model system was packaged in glass jars, polyethylene terephthalate (PET) bottles, bottles of PET containing different percentages of oxygen scavengers, and bottles of PET blended with 6% nylon. Samples were stored at 5 °C to simulate the usual storage condition and at 35 °C to simulate a temperature abuse. The slowest ascorbic acid degradation and browning were obtained with PET + 3% oxygen scavengers. Glass and PET gave the worst results: the 1st due to the presence of pro-oxidants and the latter due to the oxygen permeability. In particular, concerning ascorbic acid degradation in glass containers at 35 °C, it was hypothesized that there are 2 simultaneously occurring reactions: the 1st directly related to aerobic oxidation and the 2nd primarily due to the anaerobic consumption of ascorbic acid, which becomes predominant when oxygen is totally exhausted. Results also demonstrated the possible replacement of the glass containers with polymeric ones in the beverage industry.

Semi-preserved tomato sauces packaged in polymeric containers have gained in popularity and market share, as opposed to traditional fully preserved tomato sauces. As a consequence of the different technologies applied, microbiological, enzymatic, and chemical problems are considered and compared with those related to traditional processing. This research represents a comparative study of the influence of different packaging (glass, polyethylene terephtalate [PET], PET added with an oxygen scavenger, and polypropylene [PP]) on the quality decay kinetics of a semi-preserved sauce. Results suggest that the packages chosen for our experiments can be used interchangeably because of the scant influence of the packaging materials on most of the quality indices. Two exceptions are represented by lycopene content (whose decrease was faster in PET and PP than in glass and PET containing the oxygen scavenger) and the peroxide data (which reached the highest values for PET containers).

Carotenoid compounds in wine grapes (Chardonnay, Merlot, Primitivo, Negroamaro) grown in Apulian region were investigated by chromatographic and spectrometric analyses. Cis-isomers of lutein and beta-carotene (9Z, 9'Z-lutein and 9Z-beta-carotene) and 5,6-epoxyxanthophylls were detected: 9'Z-neoxanthin, violaxanthin, and 5,6-epoxylutein. Moreover, zeaxanthin was efficiently resolved from lutein by a selective factor > 1 (alpha= 1.06) and was found in high amounts (50 to 300 microg/kg) in the grape extracts analyzed in 3 y of study (2006 to 2008). At grape maturity, beta-carotene had concentration approximately 2-to 4-fold higher than (all-E)-lutein in all varieties. Because carotenoids are potential precursors of aroma compounds, it was determined carotenoids change DeltaC (microg/kg), from the difference of total carotenoids concentration between veraison and maturity. Chardonnay and Merlot had the highest DeltaC values and principal component analysis showed that they were characterized by 5,6-epoxyxanthophylls derivatives and zeaxanthin, lutein, and beta-carotene derivatives, respectively. An important effect of vintage on DeltaC values in the analyzed grapes was also observed. A strong positive correlation was determined between DeltaC and temperature data that seem to be responsible for the difference of DeltaC in the Chardonnay and Merlot compared to the Primitivo and Negroamaro varieties.

The aim of this study was to assess the influence of 9 winemaking technologies (traditional, delestage, saignee, 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, saignee, 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.