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The evolution of low molecular weight phenolic compounds in red wines aged in cherry ( Prunus avium ) or oak ( Quercus petrae ) wood has been investigated. In addition, the phenolic composition of hydroalcoholic extracts of cherry heartwood has been characterized and quantified by means of HPLC-DAD/MS analysis. More than 20 phenolic compounds, constitutive of cherry wood, were identified, including flavanols, flavanones, flavanonols, flavonols and flavones. During ageing, some of these compounds (eryodictiol, sakuranetin, pinocembrin and chrysin) were transferred to the wines and may represent putative phenolic markers of the usage of this wood specie. The phenolic composition of wines was significantly affected by the different woods, the cherry barriques promoting the fastest evolution of (+)-catechin, procyanidins and flavonols if compared to oak. Our findings confirmed that cherry wood is highly oxidative towards wine phenolics but, at the same time, suggested that a portion of those phenols are involved in condensation phenomena able to stabilize both the tannins and the pigments of the aged red wines.

BACKGROUND Thirty-six high-quality vinegars with geographical indication belonging to Sherry and Modena areas (vinegars of Jerez, balsamic vinegars of Modena and traditional balsamic vinegars of Modena) with all possible aging periods were analyzed to determine the content of volatile aldehydes. A solid-phase extraction method with in-cartridge derivatization using O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine followed by gas chromatography–mass spectrometry was employed. RESULTS Twenty-two volatile aldehydes were identified and determined in the samples. Analysis of variance provided significant differences among the samples as a function of the type of vinegar, aging time and raw material. Principal component analysis and linear discriminant analysis demonstrated the possibility of discriminating the samples in terms of aging time and raw material. Linear aldehydes and compounds such as furfural, methional, nonenal, hexenal, 2-methylbutanal and i-butyraldehyde were the most significant variables able to discriminate the samples. CONCLUSION Aldehyde content of premium quality vinegars is a function of both ageing time and raw material. Their evaluation could be a useful tool with a view to ascertaining vinegar origin and genuineness. © 2014 Society of Chemical Industry

The effects of some antioxidant (sulfur dioxide, ascorbic acid and gallotannins) and their mixtures, on the oxidative evolution of model wines containing (+)-catechin, have been compared by monitoring O2 consumption, browning development and (+)-catechin decay. The contextual generation of xanthylium pigments has been further evaluated with the aim of deepening our understanding of the kinetics and the mechanisms underlying the oxidative spoilage of flavanols in wine-like conditions. Novel data on the efficacy of gallotannins in controlling the (+)-catechin oxidative decay in model wine solutions are furnished, together with its comparison with the ones offered by SO2 and ascorbic acid. Ascorbic acid was found to promptly reduce the amount of dissolved oxygen in samples, while the presence of SO2 or tannins resulted in a significantly lower consumption. Under our experimental conditions and at least for 30 days, browning rate was best controlled by sulfite and ascorbic acid (even if to a different extent) while gallotannins failed in such a task. However, a longer storage (120 days) under oxidative conditions revealed a large augmentation of browning rate in samples with aa and/or SO2, added which became yellower than untreated samples. The amounts of (+)-catechin declined the fastest in all the solutions with aa added Chemical reactions underlying the obtained results, have been discussed.

Thirty-six high-quality vinegars with geographical indication belonging to Sherry and Modena areas (vinegars of Jerez, balsamic vinegars of Modena and traditional balsamic vinegars of Modena) with all possible aging periods were analyzed to determine the content of volatile aldehydes. A solid-phase extraction method with in-cartridge derivatization using O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine followed by gas chromatography-mass spectrometry was employed.Twenty-two volatile aldehydes were identified and determined in the samples. Analysis of variance provided significant differences among the samples as a function of the type of vinegar, aging time and raw material. Principal component analysis and linear discriminant analysis demonstrated the possibility of discriminating the samples in terms of aging time and raw material. Linear aldehydes and compounds such as furfural, methional, nonenal, hexenal, 2-methylbutanal and i-butyraldehyde were the most significant variables able to discriminate the samples.Aldehyde content of premium quality vinegars is a function of both ageing time and raw material. Their evaluation could be a useful tool with a view to ascertaining vinegar origin and genuineness.

The color features and the evolution of both the monomeric and the derived pigments of red wines aged in oak and cherry 225 L barriques have been investigated during a four months period. For cherry wood, the utilization of 1000 L casks was tested as well. The use of cherry casks resulted in a faster evolution of pigments with a rapid decline of monomeric anthocyanins and a quick augmentation formation of derived and polymeric compounds. At the end of the aging, wines stored in oak and cherry barriques lost, respectively, about 20% and 80% of the initial pigment amount, while in the 1000 L cherry casks, the same compounds diminished by about 60%. Ethyl-bridged adducts and vitisins were the main class of derivatives formed, representing up to 25% of the total pigment amount in the cherry aged samples. Color density augmented in both the oak and cherry wood aged samples, but the latter had the highest values of this parameter. Because of the highly oxidative behavior of the cherry barriques, the use of larger casks (e.g., 1000 L) is proposed in the case of prolonged aging times.

The efficacy of chitosan and sulfites in inhibiting the oxidation of (+)-catechin in aerated model white wines has been compared by monitoring the browning development and the generation of oxidized phenolic compounds. In addition, the protecting effects of these two additives toward the oxidative decay of varietal thiols were investigated. Chitosan effectively contrasted the browning onset in model solutions all along the entire duration of the experimentation. Color development was limited and comparable in both the sulfite and chitosan added samples. Thanks to its polyelectrolyte behavior, chitosan adsorbed up to 80% of the more hydrophilic oxidized phenolic species and chelated 70 and 30% of Fe and Cu added to the solutions, respectively. Thiol oxidation was significantly lowered by chitosan, suggesting that this additive could contribute to maintain the varietal character of wines coming from aromatic grapes and vinified with reduced sulfite amounts.

Samples of 15 commercially available batches of wood chips, used in alcoholic beverage industry, were extracted and analyzed for their content in polycyclic aromatic hydrocarbons (PAHs). Total amounts of PAHs varying between 0.96 and 15.1 ng/g of wood were found, with medium to low MW compounds being mainly present. Carcinogenic benzo[a]pyrene was found in such a value, however, not alarming if maximum mandatory levels in food are considered. PAHs content in chips was unaffected by wood origin, size or toasting level while further investigations dealing with phenomena occurring during the wood seasoning could be necessary.

This study determined the influence of the kind of wood (Allier vs Limousin and Allier vs chestnut), the age (new vs 1 year old Allier oak barriques) and the volume (1000 L vs 225 L ) of Allier oak containers on sensorial profile and volatile composition of a red Sangiovese wine during 360 days of ageing. The greatest sensory differences were found between Allier oak wood and chestnut wood barriques. In chestnut barriques, wines were more fruited and tannic than in Allier where wines were less astringent, more vanilla flavoured and well-balanced. Some differences in chemical composition and sensorial profile were observed in wines aged in used containers with different capacities. The use of containers showed that migration phenomena from wood to wine were more intense in new barriques than in used ones. Therefore, wines aged in new barriques were richer in volatile wood compounds than wines aged in old barriques.

Volatile and semi-volatile compounds of French and American oak wood used in wine and spirits ageing were extracted by an Accelerated Solvent Extractor (ASE) and analysed by gas chromatography–mass spectrometry. More than 90 compounds were isolated, characterised and quantified after being separated on two chromatographic columns with distinct polarity. The main oak wood components were quantitatively determined by using standard reference compounds. In addition, a number of compounds, mainly guaiacol and syringol derivatives, were detected and characterised. In particular, 10 compounds were tentatively identified as lignin dimers derivatives, whose presence in oak wood chips or barrels for wine and spirits ageing had not been previously described. Several of the characterised compounds enabled a distinction to be drawn between medium and high toasted wood chips, independently of their geographical origin.

Vernaccia di Oristano, a sherry-like wine produced in Sardinia, Italy, was subjected to biological aging after inoculation with Saccharomyces cerevisiae var. bayanus (strain 1043) and S. cerevisiae var. prostoserdovii (strain 1739) and to aging under sterile conditions. Samples were withdrawn at three different stages of maturation of the sherry-like wine, and the volatiles were analyzed by gas chromatography and gas chromatography/mass spectrometry. Forty compounds were identified comprising alcohols, acids, esters, and dioxolanes. Analysis of variance showed significant effects of both aging conditions and duration on most of the volatiles, with differences maximized at the final sampling time, i.e., 20 days after film formation. Keywords: Vernaccia di Oristano; sherry; flavor; gas chromatography/mass spectrometry; Saccharomyces cerevisiae var. bayanus; Saccharomyces cerevisiae var. prostoserdovii; yeasts

In this work, the effects on the volatile profile of the pre-fermentative substitution of SO 2 with lysozyme and oenological tannins were studied in white wines. At the same time, in order to understand the changes of volatile compounds in SO 2 -free wines, the evolution of volatiles was evaluated over 1 year of storage in bottles. For this purpose, a number of laboratory scale fermentations of Sauvignon Blanc musts were carried out and the effects of three variables (SO 2 , lysozyme and oenological tannins) were investigated by means of GC–MS analysis. Results showed that the replacement of SO 2 with lysozyme and oenological tannins influenced the volatile composition of wines at the end of the alcoholic fermentation. Wines fermented with SO 2 showed higher total alcohol amounts, while the presence of oenological tannins augmented the level of esters. The presence of SO 2 influenced also the alcohols and esters profiles of wines during bottle storage. Moreover, the presence of oenological tannins displayed a positive role in maintaining the amounts of esters over certain levels in wine stored for 1 year, likely due to their oxygen scavenging ability. By contrast, acids were less affected by the investigated adjuvants both at the end of the alcoholic fermentation and during the storage time.

The volatile composition of 26 premium quality vinegars belonging to three different protected geographical indications (traditional balsamic vinegar of Modena, balsamic vinegar of Modena, and sherry vinegar) has been characterized by means of a solid-phase extraction (SPE) gas chromatography-mass spectrometry GC-MS method. Among the about 90 quantified compounds, short-chain fatty acids, furanic compounds, enolic derivatives, and some esters were found to discriminate the samples as a consequence of differences in the extent of Maillard reactions, presence of alcoholic fermentation, or duration of wood aging.

Thirty commercially available Italian carbonic macerated young red wines, have been analysed by HPLC–DAD–MS with the aim to characterise their pigment composition and find possible correlations with the colour features evaluated by means of spectrophotometric measurements. The composition in anthocyanin monoglucosides, acetates, p-coumarates as well as that in pyranoanthocyanins and direct and ethyl-bridged adducts with flavanols, was studied. Because of the peculiar maceration process, carbonic macerated wines demonstrated to be qualitatively rich in pyranoanthocyanins and pigment adducts. A number of ethyl-bridged anthocyanin isomers was found, together with significant contents of vitisin A and vitisin B (up to 15.5 mg/L as a sum). Malvidin-3-glc-4-vinylphenol was the main pyranoanthocyanin-vinylphenol adduct (up to 1.10 mg/L). The colour features of the wines were broadly distributed as a consequence of the percentage of carbonic macerated wine present in the marketed product. The statistical treatment of the entire data set revealed that pyranoanthocyanins are positively correlated with colour density (while no correlation was found for monoglucosides) and that direct adducts and/or ethyl-bridged compounds can play a role for what concerns the hue of carbonic macerated wines.

BACKGROUND: In recent years the use of sulfur dioxide, a commonly used additive in winemaking, has been questioned because of its toxic effects on human health. Studies have been conducted to find alternatives that can effectively substitute for this additive in all its various technological functions. In previous work, lysozyme and oenological tannins were found as possible substitutes in controlling bacterial undesirable fermentations and phenolic oxidation. However, data on the volatile composition of wines obtained by that protocol are lacking. In this work, the effects on volatile composition of white wines by the substitution of SO2 during fermentation with lysozyme and tannin were studied. At the same time, the technological performance of two strains of yeast that produce low amounts of SO2 were evaluated. RESULTS: The results showed that both SO2 and lysozyme prevented the development of undesirable bacterial fermentations. The study of volatile compounds shows differences in the alcohol, acid and ester contents among the final products: wines fermented with strain 1042 and lysozyme had higher total alcohol concentration, while the addition of SO2 promoted higher production of 3-methyl-1-butanol, 3-methylthio-1-propanol, phenylethyl alcohol and 4-hydroxy-benzenethanol. Esters, as a total, were influenced by the different strain and tannins addition, while amounts of medium-chain fatty acid ethyl esters and their corresponding fatty acids were found in higher amounts in wines coming from fermentations with lysozyme. The sensory analysis revealed a preference for wines to which lysozyme and tannins had been added. CONCLUSION: The data suggest that the addition of lysozyme and oenological tannins during alcoholic fermentation could represent a promising alternative to the use of SO2 and for the production of wines with reduced content of SO2. The composition of the volatiles in the final wines was affected by the different vinification protocols (mainly with regards to alcohols and ethyl esters). Copyright © 2009 Society of Chemical Industry

A solid-phase extraction method for the determination of volatile compounds in traditional balsamic vinegar (TBV) has been developed. The optimisation has been carried out using a two-level factorial design expanded further to a central composite design. LiChrolut-EN SPE cartridges were used and the optimised analytical conditions were: 7 g of TBV diluted 1:4, 5 mL of washing water, and elution with 10 mL of dichloromethane. The linear ranges and detection and quantitation limits were adequate for the analysis of the studied compounds in TBV. The accuracy of the method was also studied: recoveries up to 80% and repeatability values lower than 15% were obtained for the majority of the studied compounds. Two TBVs of different age were analysed by the optimised method.

Sixteen commercially available oak chips, differing in origin (French or American) and toasting level, were extracted by an accelerated solvent extraction method and characterized by their volatile composition. About 80 compounds were identified and quantified, a great part of them from the thermodegradation of lignin and cellulose. One furanone (solerone) and two C-13 norisoprenoids (3-oxo-α-ionol and a 3-oxoretro-α-ionol isomer) were also tentatively identified and reported for the first time in toasted wood. Quantitative data demonstrated the oak chips to be not so different from the composition of light- or medium-toasted wood barrels, which was reported by other authors. The same data suggest that toasting level had the strongest influence on the volatile composition of chip samples. Phenyl ketones, volatile phenols, and some furanic compounds were the most influenced. On the other hand, the influence of wood origin was found to be weaker. Keywords: Oak chips; GC-MS; ASE; wine; wood aging; volatile c...

A rapid HPLC-DAD determination of phenols in apple using an RP monolithic column is reported. Because of the hydrodynamic advantages offered by this kind of column and the use of acidified acetonitrile as eluent, assays of apple extracts can be performed in

A pilot plant system for dealcoholizing wine using solid carbon dioxide snow was evaluated. Wines were stripped of alcohol content by spraying them over solid phase CO2. Gas leaving the solid-liquid contact zone carried ethanol which was recovered by condensation. White wine lost alcohol easier than red wine and some higher alcohols were removed at levels which paralleled ethanol removal. Other solutes remained at about the same levels as in the untreated wine.

Ad eccezione delle occasioni in cui la presenza di ossigeno sia una pratica enologica desiderata (ad esempio, ossigenazione controllata dei vini rossi), nella grande maggioranza dei casi il contatto (involontario) dei vini con l’ossigeno si traduce in un peggioramento della qualità complessiva del prodotto. L’insieme dei fenomeni che presiedono all’evoluzione ossidativa dei vini è assai complesso. Questa complessità è dovuta, in primo luogo, alla presenza di un consistente numero di sostanze (endogene o aggiunte nel corso del processo produttivo) in grado di partecipare al processo di ossidazione, rendendone talvolta imprevedibili le fasi e l’entità complessiva. Sebbene utilizzata da oltre un secolo, ad esempio, solo negli ultimi 15 anni si sono definite con maggior esattezza le interazioni ed i meccanismi chimici coinvolti nell’attività antiossidante della SO2. Questa molecola, principale additivo utilizzato nella filiera enologica per il controllo delle ossidazioni, è in grado di esplicare la propria azione attraverso una serie di reazioni che coinvolgono, tra l’altro, a seconda della loro presenza nel mezzo, le sostanze fenoliche (gli o-difenoli), i metalli (soprattutto Cu+ e Fe++), l’acido ascorbico o il glutatione. D’altro canto, le caratteristiche allergeniche dell’anidride solforosa hanno stimolato i produttori verso la riduzione del suo uso in vinificazione e alimentato la ricerca di possibili alternative tecnologiche. In questa ottica, l’utilizzo dell’acido ascorbico ha fornito risultati contrastanti, spesso legati alla necessità della contemporanea presenza di adeguate quantità di anidride solforosa ad evitare fenomeni pro-ossidativi. L’uso di tannini idrolizzabili è una ulteriore opzione a disposizione degli enologi che vogliano limitare i problemi legati all’ossidazione dei vini. Il tannino di galla, in particolare, ha dimostrato di possedere una rilevante capacità antiradicalica, sebbene pochi siano gli studi riguardanti un suo utilizzo in condizioni assimilabili a quelle del vino. Questo lavoro si è proposto di indagare gli effetti della presenza di SO2, acido ascorbico e tannino di galla, da soli od in combinazione, sulla ossidazione di una soluzione modello contenente (+)-catechina. Per ciascuna tesi predisposta è stato valutato il consumo di ossigeno disciolto, l’imbrunimento e la cinetica del consumo di (+)-catechina. Allo stesso tempo, è stata valutata la progressiva formazione degli ioni xantilio, pigmenti responsabili dello sviluppo delle nuances gialle tipiche delle soluzioni sottoposte ad ossidazione. I possibili meccanismi ossidativi sono stati discussi alla luce dei risultati ottenuti.

L’affinamento in legno è una tecnica idonea alla produzione di vini di qualità. Il contatto con il legno, infatti, oltre a favorire la migrazione nel vino di sostanze aromatiche, permette la dissoluzione di quantità di ossigeno in grado di promuovere la stabilizzazione della sostanza colorante e l’evoluzione della componente tannica del prodotto. Per questi fenomeni, un ruolo rilevante è ricoperto dalle catechine, dalle procianidine oligomere e, più in generale, da tutti quei composti fenolici in grado di interagire con l’ossigeno. La presenza e l’evoluzione di questi polifenoli nei vini in fase di affinamento è funzione della dotazione iniziale del prodotto, dell’entità dei fenomeni ossidativi e della cessione da parte dell’essenza legnosa impiegata. Tradizionalmente, le specie legnose utilizzate per l’affinamento di vini e distillati appartengono al genere Quercus spp. Negli ultimi anni, però, altre specie di uso locale hanno suscitato l’interesse dei produttori, grazie ai minori costi o al positivo contributo sensoriale. In questo lavoro, dopo aver caratterizzato la frazione fenolica estraibile da legno di ciliegio (Prunus avium), si è valutata l’evoluzione dei composti fenolici non antocianici in vini rossi affinati per 4 mesi in barriques o fusti ottenuti con lo stesso tipo di legno. I risultati sono stati posti a confronto con quelli ottenuti con l’utilizzo di barriques di rovere. L’uso di legno di ciliegio è stato contraddistinto dalla presenza, nel vino, di alcuni flavoni che potrebbero considerarsi markers del trattamento.

Sedici partite di chips di quercia, reperibili dal commercio e diverse per livello di tostatura (non tostato, media od alta tostatura) e per origine (Quercia francese od americana), sono state estratte mediante tecnica ASE (Accelerated Solvent extraction) e caratterizzate relativamente alla loro componente volatile. L’analisi della frazione volatile, condotta in GC/MS, ha permesso di identificare e quantificare circa 80 molecole, 3 delle quali (solerone, 3-oxo-ionolo ed un isomero del 3-oxoretro--ionolo) individuate per la prima volta in legni tostati ad uso enologico. I dati quantitativi hanno dimostrato che i chips legnosi posseggono un patrimonio aromatico paragonabile a quello di barriques e fusti di quercia a leggero o medio livello di tostatura e che l’aumento delle temperature di tostatura influisce in maniera significativa sulla presenza di fenilchetoni, fenoli volatili ed alcuni composti furanici. Assai limitata è risultata l’influenza dovuta all’origine della materia prima, probabilmente anche a causa dell’estrema variabilità esistente fra i campioni appartenenti a ciascun gruppo. Le stesse partite di frammenti legnosi, sono state sottoposte ad estrazione soxhlet ed analisi HPLC-FLD allo scopo di indagare l’eventuale presenza di idrocarburi policiclici aromatici (IPA). Sono stati quantificati bassi tenori totali di IPA (compresi fra 0,96 e 15,1 ng/g di legno), principalmente costituiti da molecole a basso o medio peso molecolare. Fra queste figura il benzo[a]pirene, la cui concentrazione massima è risultata essere pari a 0.44 ng/g di legno. Tenuto conto dei livelli di IPA attualmente ammissibili in Europa per bevande aromatizzate ed acqua, i valori riscontrati non rappresentano un ostacolo all’utilizzo dei frammenti legnosi in enologia.

E’ stato definito e validato un metodo RP-HPLC per la quantificazione di lisozima da bianco d’uovo, in vini bianchi e rossi. Grazie all’utilizzo di un detector spettrofluorimetrico, il metodo proposto ha mostrato una sensibilità dieci volte più alta rispetto alla comune rivelazione spettrofotometrica a 280 nm. I parametri in grado di influire sulle prestazioni del metodo (separazione cromatografia, interferenza della matrice, modalità di acidificazione e stabilità della risposta fluorimetrica) sono stati valutati ed ottimizzati. La procedura di validazione della metodica ha mostrato buoni valori di ripetibilità, riproducibilità e recupero, con un sensibile incremento del livello minimo di lisozima rivelabile (pari a 0.18 mg/L). Il metodo proposto può essere applicato ai vini, con fini tecnologici e l’aumento della sua sensibilità analitica può rappresentare un valido strumento per la tutela della salute di quei consumatori potenzialmente sensibili alla proteina.