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The natural occurrence of ochratoxin A (OTA) and cis- and trans-resveratrols in red wines has been widely reported. The aim of this work was to evaluate the ochratoxin A (OTA) and both cis- and trans-resveratrol content of red wine (from must to wine) in a pilot-scale vinification process in Calabria (Italy). Eleven samples were collected at different stages of vinification and analysis was carried out by HPLC. Wine from manufacturer 3 contained the highest amount of trans-resveratrol (3.41?mg?l?1). This wine was characterized by an Aglianico–Magliocco grape variety. Interestingly, data regarding OTA showed that the value of this contaminant was low in all analyzed samples and, in each case, below the legal limit (2.0?mg?l?1 (ppb)). Overall, the results demonstrated the high quality of wines produced in Calabria.  相似文献   

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The natural occurrence of ochratoxin A (OTA) and cis- and trans-resveratrols in red wines has been widely reported. The aim of this work was to evaluate the ochratoxin A (OTA) and both cis- and trans-resveratrol content of red wine (from must to wine) in a pilot-scale vinification process in Calabria (Italy). Eleven samples were collected at different stages of vinification and analysis was carried out by HPLC. Wine from manufacturer 3 contained the highest amount of trans-resveratrol (3.41 mg l(-1)). This wine was characterized by an Aglianico-Magliocco grape variety. Interestingly, data regarding OTA showed that the value of this contaminant was low in all analyzed samples and, in each case, below the legal limit (2.0 mg l(-1) (ppb)). Overall, the results demonstrated the high quality of wines produced in Calabria.  相似文献   

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Pyruvic acid (500 mg/l) and acetaldehyde (200 mg/l) were added, either as a large single dose or as smaller weekly doses over a 10 week period, to a young red wine (Vitis vinifera L. cv Tempranillo) in order to study the formation of vitisin A and B, and p-coumaroylvitisin A and B. In a further trial, pyruvic acid and acetaldehyde were added simultaneously as a single administration to test for any synergistic effect on vitisin formation. The addition of pyruvic acid led to the production of higher concentrations of vitisin A (4.08 ± 0.86 mg/l; 2.03% of the total anthocyanin content), while additions of acetaldehyde increased the concentration of vitisin B (2.47 ± 0.09 mg/l; 1.35%). The single, large dose administrations led to greater vitisin formation than did the smaller, weekly doses. Different patterns of formation were seen for vitisin A and B: the highest vitisin A content was achieved during the latter half of the 10 week study period while the highest vitisin B concentration was achieved early. The addition of acetaldehyde produced a greater reduction in monomeric anthocyanins than did the addition of pyruvic acid (loss of total anthocyanins 81.5%). The simultaneous addition of pyruvic acid and acetaldehyde led to less vitisin formation than did the addition of the reagents separately. p-Coumaroylvitisin A reached a maximum concentration of 0.86 ± 0.15 mg/l when the single dose of pyruvic acid was added, while the maximum recorded for p-coumaroylvitisin B was 0.66 ± 0.05 mg/l when the single dose of acetaldehyde was added. All anthocyanins were identified using HPLC/DAD and HPLC/ESI–MS.  相似文献   

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The two main phenolic compounds, namely anthocyanins and tannins, and some chromatic characteristics have been determined in 437 samples of red and white wines from northwest of Spain, which were commercialised in two consecutive years (2005 and 2006). The variation range for total polyphenol index (TPI) was 4.1–16.6 and 27.8–91.9 in white and red wines, respectively. Standard parameters were also investigated. The classification successful by Denominations of Origin was near 50% for both red and white wines. Statistical correlations among standard and colour parameters were established to find a simple methodology usually used in winery that permits to provide more complete information for the oenologist. So, a significant correlation was found for TPI or chromatic intensity and volume mass in red wines (0.547–0.583, P < 0.01), while tonality can be estimated from pH (0.601, P < 0.01). No lineal relationship was found in white wines.  相似文献   

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Health benefits of red wine have been ascribed in part to the antioxidant properties of quercetin and other flavonols. Red wines, however, contain many other polyphenolic compounds with antioxidant potential. The present study has assessed the antioxidant capacity of seven red wines using electron spin resonance spectrometry to measure their ability to donate hydrogen atoms to a stable Fremy's radical. Antioxidant capacity of the wines was strongly related to the total phenol content (r = 0.872, P < 0.01) but less so to total flavonol content (r = 0.651, P < 0.10). The only flavonols detected in the wines by HPLC with post‐column derivatisation were the aglycones and conjugated forms of quercetin and myricetin. These accounted for less than 2% of total phenolic content when expressed as gallic acid equivalents. Although these flavonols showed marked ability to quench Fremy's radical, they contributed less than 1.5% to the total antioxidant capacity of the wines. Consequently, quercetin is not a major antioxidant in red wine. The antioxidant activity of other polyphenols may be of greater importance in contributing to the reputed health benefits of moderate wine consumption. © 1999 Society of Chemical Industry  相似文献   

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Studies in young animals have shown an association between vitamin deficiencies and increased risk of infectious disease; however, there is a paucity of information regarding the effect of acute infection on the vitamin status of the vitamin-replete neonate. To characterize the effects of acute infection on vitamin D and E status of the neonate, 6 vitamin-replete preruminant Holstein bull calves were experimentally infected with bovine viral diarrhea virus (BVDV; strain BVDV2-1373). Six mock-inoculated calves served as controls. Sustained pyrexia, leukopenia, and asynchronous increases in serum haptoglobin and serum amyloid A characterized the response of calves to infection with BVDV. Infection was also associated with increased serum IFN-γ, IL-2, and IL-6 concentrations. During the last 8 d of the 14-d postinoculation period, serum 25-hydroxyvitamin D and α-tocopherol concentrations in infected calves decreased by 51 and 82%, respectively. The observed inverse association between vitamin D and E status and serum amyloid A in infected calves suggests that the infection-induced acute phase response contributed to the reduced vitamin status of these animals. Additional studies are necessary to determine if the negative effect of infection on status are unique to this specific infection model or is representative of preruminant calf’s response to acute infection. Studies are also needed to characterize mechanisms underlying infection-related changes in vitamin D and E status and to determine whether additional vitamin D or E supplementation during an acute infection diminishes disease severity and duration in the young animal.  相似文献   

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Tintilia is an autochthonous grapevine of the Italian Molise region which risked to disappear. However, recently, the production of Tintilia red wines is resuming and in the year 2011 the protected designation origin ‘Tintilia del Molise’ was officially registered. In this work, an analytical characterization of representative red wines from Tintilia grape is reported. A total of 36 different physicochemical variables were determined and discussed, considering those with an estimated coefficient of variation <25 % as more characterizing. These were found to be (mean): density (0.9949); dry extract (34.4 g L?1) and ashes (3.8 g L?1); ethyl alcohol (14.2 mL 100 mL?1), glycerol (9.2 g L?1) and total higher alcohols (1.7 g L?1); pH (3.65); the titratable (5.9 g L?1), fixed (5.4 g L?1), and salified (2.5 g L?1) acidity; buffering capacity (52.6 mM/L/pH); total phenols (2,341 mg mL?1); total flavonols (223 mg mL?1) and epicathechin (75.0 mg mL?1); %Red (49.1 %) and %Yellow (43.6 %). Sensory analysis was also performed by professional wine tasters. Finally, the Tintilia results were compared with those of Montepulciano wines. Findings of this analytical study describe the Tintilia red wine as a full-bodied wine; alcoholic; with feeble, but stable acidic profile; rich of phenols, especially flavonols; and finally, with a color balanced between red and yellow pigments.  相似文献   

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As furfural (F) and 5-hydroxymethylfurfural (HMF) are essentially formed from sugar dehydration, especially in food submitted to heat, they can be found in beverages, as well as fortified sweet wines. In order to assess the impact of temperature on Madeira winemaking, three traditional varieties of Madeira wines (Malvasia, Sercial and Tinta Negra Mole) were studied to evaluate the F and HMF contents. The wines were produced by two vinification processes, following traditional and modern methodologies, heated at standard conditions (30 °C and 45 °C, for 4 months) and compared with the same wines submitted to overheating conditions (55 °C, for 4 months). The RP-HPLC-DAD methodology used for the control of F and HMF during the process showed no significant changes in the wines maintained at 30 °C (canteiro) and a noticeable but controlled increase in the wines heated at 45 °C (estufagem) where values up to about 150 mg/L of HMF could be found in sweet wines. The strong relation of this compound with the sugar content and baking temperature stood out in the wines submitted to overheating conditions where values higher than 1 g/L could be found for sweeter wines, with HMF level being in general higher than F.The results clearly suggest that the amount of HMF in these fortified wines can be easily controlled when submitted to adequate conditions of heating during estufagem and storage. Furthermore, different temperatures for the baking of sweet and dry wines may be considered.  相似文献   

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In red beet (Beta vulgaris L. var. conditiva) the main degradation product of added nitrapyrin [2-chloro-6-(trichloromethyl)-pyridine] has been shown to be 2-chloro-6-(dichloromethyl)-pyridine. The distribution of these two compounds in beet was also studied. The highest content of nitrapyrin residues (dry weight) was found in the root tips and the petioles; the peel contained more than the leaf laminae or other parts of the root. The higher the nitrapyrin content, the higher was the ratio of nitrapyrin to its dechloro form. No clear linear correlation was observed between the content of nitrapyrin and its dechloro form. The amounts of nitrapyrin residues in beet treated with Ca(NO3)2 were smaller than in the respective samples of beet fertilised with urea or NH4NO3.  相似文献   

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This paper describes the development and application of a fast and simple headspace solid phase microextraction GC–MS method for simultaneous determination of geosmin and 2,4,6-trichloroanisole (2,4,6-TCA), two main contributors to off-flavors in wine. The compounds were adsorbed onto a polydimethoxysiloxane (PDMS) fiber at 35 °C for 40 min without prior equilibration, thermally desorbed and analyzed by GC–MS in the selected ion monitoring mode. The parameters for adsorption onto and desorption from the fiber were optimized. This method was applied to analysis of 118 Austrian white and red wines, which were also characterized by sensory analysis. Geosmin was above the limit of detection (0.5 ng/L) in 110 wines (93%) and additionally quantified (>2 ng/L) in 65 wines (55%). It could be detected in wines of each off-flavor (moldy, corky, damp, musty, rotten, woody, grassy) in concentrations up to 16.7 ng/L and even in 90% of the sensorially faultless wines (up to 6.5 ng/L). On the other hand, 2,4,6-trichloroanisole was detected only in 24 wines (20% of all investigated wines) and above the limit of quantitation (2 ng/L) only in 5 wines (4%) sensorially classified as corky; corky and moldy plus other defects; or faultless in concentrations up to 14.3 ng/L. These results show that geosmin is more prevalent than 2,4,6-TCA and that chemical analysis is required especially when other wine characteristic flavors cover beginning off-flavors.  相似文献   

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Individual variation in the perception of saccharin has been related to genetic sensitivity to the bitterness of 6-n-propylthiouracil (PROP). But, data on other intense sweeteners are sparse, particularly when tasted in real foods. The objectives of this study were (1) to identify the sensory attributes of intense sweeteners that influenced perception and acceptability of citrus-flavored model soft drinks and (2) to investigate the influence of PROP taster status on these responses. The sweeteners were: 10% and 8% high-fructose corn syrup (HFCS) (controls), sucralose (SUC), aspartame (ASP), acesulfame-K (ACE), ASP/ACE and SUC/ACE. Twenty-nine PROP non-tasters (NT) and 30 PROP super-tasters (ST) rated nine attributes for intensity and liking. Data were analyzed using principal component analysis (PCA). The sweeteners were described in three dimensions. Factor 1 was a bitter-citrus contrast for which overall liking was associated with higher citrus impact and lower bitterness. Factors 2 and 3 were related to overall flavor and carbonation, respectively. The sensory profiles of ASP, ASP/ACE and SUC were most similar to 10% HFCS. SUC/ACE was more bitter and less acceptable than 10% HFCS; ACE was the most bitter and was liked the least. PCA also revealed that NT placed more emphasis on the perception of sweetness and citrus flavor (Factor 1; 37% variance), whereas ST tasters placed more emphasis on bitterness (Factor 1; 43% variance). Liking was uniquely related to lower bitterness for NT. For ST, liking was negatively related to bitterness and weakly positively related to persistence of sweetness. These data suggest that ST experience intense sweeteners differently than NT but these differences play a minor role in soft drink acceptance.  相似文献   

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Wines are the subject of increasing numbers of investigations owing to the pharmaceutical usefulness of grape phytochemicals. The aim of the present work was to hypothesize the use of lyophilised red wines for the formulation of food supplements potentially useful against both physiological and induced cardiac oxidative stress. Cardiac derived H9C2 myocytes were incubated with increasing doses (0.01–1 μg) of lyophilised Aglianico wine (lioAW). Experiments showed an appreciable direct radical scavenging activity at a maximum lioAW dose of 0.03 μg that made the caspase-3 activity decrease by about 41%. Cardiac cells were exposed to 1 μM doxorubicin and its combination with different doses of lioAW. Maximum lioAW aliquot of 0.03 μg seemed to effectively contrast the induced oxidant injury decreasing the reactive oxygen species (ROSs) levels by about 38%and depressing the caspase-3 activity by about 63%. In both assays, pro-oxidant effects at higher lioAW concentrations were detected.  相似文献   

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The microbiota of eight spontaneous fermentation of white wine from different grape varieties and different wineries from the "Txakoli de Bizkaia" region (Basque country, North Spain), in 1996 and 1997 campaigns was studied. The yeast population was higher in grapes harvested in 1997, in which late summer and early autumn was warmer and drier. Eight species belonging to five genera were identified in total. The most frequent genera in grapes were Rhodotorula in 1996 and Kloeckera in 1997. Saccharomyces bayanus was the most frequent species during vigorous and final fermentation, and it was occasionally isolated from grapes and must. Only another Saccharomyces spp., i.e., S. kluyvery, was identified in some samples from 1997.  相似文献   

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Wine quality study was carried out with 24 vintages of Cabernet-Sauvignon (CS) and 7 vintages of Merlot (M) produced by two different Bordeaux wine-growing areas. Proanthocyanidin monomers and oligomers were identified and quantified by HPLC-UV-Fluo. Percentage of galloylation (%G), of prodelphinidins (%P) as well as mean degree of polymerisation (mDP) were also determined. Total phenolic compounds, total anthocyanins, total tannins, hue, CI (colour intensity), titratable acidity, ethanol level and pH were evaluated. Sensory analysis concerning astringency and bitterness intensity was also performed. Total phenolic compounds, total anthocyanins, total tannins, tannin monomers, hue, CI, % G, % P, mDP and astringency intensity differentiate both wines (M and CS) according to vintage. Correlations between wine age and: mDP, hue, astringency and tannin monomers (C + EC) are obtained. Qualitative tannin characterisation is established by correlation between astringency and mDP (R2 = 0.509, p = 0.051, CS; R2 = 0.780, p = 0.000 M). In addition, mDP decreases significantly during ageing (R2 = 0.796, p = 0.000; CS and R2 = 0.946, p = 0.000; M). Scale patterns between wine mDP and tannin perception (astringency) are proposed.  相似文献   

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