0000000000044408
AUTHOR
M Squadrito
Evoluzione degli aromi varietali durante l’appassimento dell’uva Moscato d’Alessandria
Caratterizzazione del contenuto aromatico e dei profili trascrizionali di geni coinvolti nella biosintesi degli aromi durante lo sviluppo dell’acino di un vitigno aromatico
Variazione territoriale della temperatura alla toposcala e qualità dell'uva della cv Nero d'Avola
Composizione polifenolica e maturazione di vin “Nero d’Avola” prodotti nell’ambiente della Sicilia occidentale
Beneficial effects of Candida zemplinina in wine fermentation: lower alcohol level and higher glycerol content
Aromatic varietal polyphenols of sicilian autochthouns cultivars
FACTORS AFFECTING THE SPECTROPHOTOMETRIC QUANTIFICATION OF FLAVONOIDS IN WINE
The quantification of flavonoids in wine and grape skin extract by spectrophotometric evaluation at 280 nm wavelength provides essential information to oenologist concerning wine composition and evolution, and it is commonly applied in wine labs. The measurement of the absorption peak height at 280 nm reported by DI STEFANO and GUIDONI (1989) allows to selectively quantify flavonoids with minor interferences. However, it has proved to be susceptible to SO2 at low pH or acetone in unpurified grape skin extracts. Moreover, the effect of pH on flavonoids quantification in wine, either containing SO2 or not, has not been assessed. The effect of SO2, purification, pH and dilution solvent on spec…
Over-evaluation of total flavonoids in grape skin extracts containing sulphur dioxide
Abstract Sulphur dioxide (SO 2 ) proved to increase absorbance at 280 nm of grape skin and seed extracts containing it, diluted with ethanol–HCl to assess total flavonoids and anthocyanins in the same analysis. Additional absorbance at 280 nm was also observed in acetone:H 2 O extracts, if the acetone had not completely evaporated before the extracts were diluted with a solvent. Flavonoids were correctly quantified in the extracts when SO 2 or acetone were removed by solid-phase extraction with a C 18 RP as sorbent and methanol as eluting solvent.
Tecnica dell’acidificazione dei vini per diminuire il pH o incrementare l’acidità totale
Produzione di vini rosati con affinamento sur lies
Evoluzione degli antociani e dei flavonoidi durante la maturazione di uve autoctone e internazionali nell’ambiente della Sicilia Occidentale.
In the 2006 vintage was followed the evolution of total anthocyanis and total flavonoids of skins as well as of monomer catechins, dimer procyanidins and total flavonoids of seeds of Nero d’Avola, Syrah, Merlot and Cabernet sauvignon berries, in environments of average hill of western Sicily, warm - arid during the maturation period (from 18 to 21 August the temperatures overcome 40 °C). The situation of stress, caused by the high temperatures registered in the above period, even if negatively influenced the synthesis of the anthocyanis, did not induce important variations in the profiles of these molecules that remained quite invariant especially in Nero d’Avola and Syrah. The consequences…
Candida zemplinina for Production of Wines with Less Alcohol and More Glycerol
We developed a new protocol for winery mixed fermentations, using the selected Candida zemplinina yeast strain Cz3. The results of a two-year study, in which red musts (Merlot in 2010; Merlot, Nero d’Avola and Frappato in 2011) were inoculated with Cz3, is discussed. These wines were compared with wines obtained by inoculation with commercial Saccharomyces cerevisiae yeast strains (NDA21 and AR06 in 2010; NDA21 in 2011), or with those obtained by spontaneous fermentation (only in 2011). The inoculation of Cz3 always resulted in a two-phase fermentation: the first phase was driven by the C. zemplinina strain, while the second was dominated by the indigenous S. cerevisiae yeasts coming from t…
Flavonoid profiles of Sicilian grape skin cells might diverge from a commonly accepted paradigm.
Maturazione dei vini rosati "sur lies"
Un vino rosato prodotto con uve Nero d’Avola nella Sicilia nord occidentale è stato sottoposto a maturazione per circa otto mesi in vasche di acciaio e in barriques, senza “lies”, “sur lies totales” di fermentazione e “sur lies” di Chardonnay. Le prove maturate “sur lies” di Chardonnay e quelle maturate “sur lies total” di fermentazione avevano un contenuto in pigmenti più elevato del “controllo” (probabilmente per l’effetto protettore esercitato dai polisaccaridi derivati dalla lisi delle cellule del lievito sui pigmenti). Le prime erano le meno dotate in antociani a causa della diluizione provocata dall’aggiunta delle lies sospese nel vino Chardonnay e del parziale assorbimento da parte d…
Orientamento dei filari e sfogliatura: effetti sulla qualità dell’uva nella cv Cabernet Sauvignon
La prova è stata svolta, nelle stagioni vegeto-produttive 2006 e 2007. Un trattamento di defogliazione precoce (DP) è stato, eseguito nel periodo compreso tra l’allegagione e la fase acino pisello (ø = 5 mm), mentre un trattamento tardivo (DT) è stato effettuato all’invaiatura (ø = 10,5 mm). Nel 2006, gli acini provenienti dalle piante defogliate precocemente hanno raggiunto il massimo contenuto di antociani per acino con circa 15 giorni di anticipo e con un valore superiore rispetto a quelli della tesi controllo, mentre nel 2007 l’ondata di calore verificatasi in agosto ha annullato gli effetti del trattamento. Il trattamento DT, esponendo gli acini a intensi flussi radiativi, ha causato, …
Influence of different dehydration levels on volatile profiles, phenolic contents and skin hardness of alkaline pre-treated grapes cv Muscat of Alexandria (Vitis vinifera L.)
A dehydration experiment was carried out on Vitis vinifera L. cv Muscat of Alexandria (synonym Zibibbo) following the process for the production of renowned special dessert wines produced on Pantelleria island (Sicily, Italy). Harvested berries were pre-treated in a sodium hydroxide dipping solution (45 g/L, dipped for 185 s, 25 °
Use of fortified pied de cuve as an innovative method to start spontaneous alcoholic fermentation for red winemaking
Background and Aims: Some wineries, in order to promote the growth of yeasts able to ferment grape musts, traditionally produce wines using the ‘pied de cuve’ method. The aim of the present work was to study the performance of fortified pied de cuve (FPdC) prepared by addition of wine. Method and Results: Two FPdCs were prepared with the addition of wine at 1.5 and 3% (v/v) of ethanol to the musts and allowed to spontaneously ferment. The FPdCs were then added to fresh bulk musts in order to accelerate the spontaneous alcoholic fermentation (AF). Interestingly, several Saccharomyces cerevisiae strains isolated during the pied de cuve preparation were detected at the highest concentration th…
Use of Kluyveromyces marxianus to Increase Free Monoterpenes and Aliphatic Esters in White Wines
An increasing interest in novel wine productions is focused on non-Saccharomyces yeasts due to their potential in improving sensory profiles. Although Kluyveromyces marxianus has been originally isolated from grapes and its enzymatic activities are used in oenology, rarely it has been used as co-starter. The K. marxianus Km L2009 strain has been characterized here and selected as a co-starter both at laboratory- and winery-scale fermentation. The Km L2009 strain showed growth of up to 40 (mg/L) of sulfites and 6% (v/v) of ethanol. Gas chromatographic analysis demonstrates that wines produced by mixed fermentation contain remarkably higher quantities of free monoterpenes and aliphatic esters…
Caratterizzazione del contenuto aromatico e dei profili trascrizionali di geni coinvolti nella biosintesi degli aromi durante lo sviluppo dell’acino di un vitigno aromatico
Fermentazioni miste Candida – Saccharomyces per la produzione di vini rossi con maggiore contenuto di glicerolo
Evolution of anthocyanin profile from grape to wine
<p style="text-align: justify;"><strong>Aims</strong>: This study aimed at acquiring knowledge of the evolution of anthocyanins from grape to wine and the possibility of deducing the varietal origin of a wine from its anthocyanin profile.</p><p style="text-align: justify;"><strong>Methods and results</strong>: The anthocyanin « fingerprint », or profile, of a series of autochthonous Sicilian accessions and their respective young wines was determined by HPLC-DAD in 2008. Data were evaluated by taking into account the evolution of the percentages of side-ring dioxygenated and tri-oxygenated anthocyanins, the ratio between acetylated and p-coumaroylate…
Esperienze di vinificazione di uve Grillo con protezione del mosto dalle ossidazioni
Affinamento dei vini rossi sur lies
Effetto dell'epoca di sfogliatura sul comportamento vegeto produttivo della cv Cabernet Sauvignon in Sicilia
Assessment of Postharvest Dehydration Kinetics and Skin Mechanical Properties of “Muscat of Alexandria” Grapes by Response Surface Methodology
The dipping of berries in a dilute solution of sodium hydroxide during a short time was evaluated as pretreatment undertaken prior to convective dehydration of wine grapes. The impact of the sodium hydroxide content and dipping time on weight loss (WL) at different dehydration times was thoroughly assessed using central composite design (CCD) and response surface methodology (RSM). Furthermore, the effects of these two variables were also investigated on the skin mechanical properties of dehydrated grapes. The effect of these two pretreatment factors on the dehydration kinetics and skin hardness was satisfactorily fitted to regression models. The berry pretreatment with low sodium hydroxide…
Use of fortified pied de cuve as an innovative method to start spontaneous alcoholic fermentation for red winemaking
Background and Aims Some wineries, in order to promote the growth of yeasts able to ferment grape musts, traditionally produce wines using the ‘pied de cuve’ method. The aim of the present work was to study the performance of fortified pied de cuve (FPdC) prepared by addition of wine. Method and Results Two FPdCs were prepared with the addition of wine at 1.5 and 3% (v/v) of ethanol to the musts and allowed to spontaneously ferment. The FPdCs were then added to fresh bulk musts in order to accelerate the spontaneous alcoholic fermentation (AF). Interestingly, several Saccharomyces cerevisiae strains isolated during the pied de cuve preparation were detected at the highest concentration thro…