A typical ageing note. Can ascorbic acid help?
Schneider,-V
Deutsche-Weinmagazin. 2004; (2): 16-19 ; 18 ref.
Possible use of ascorbic acid to prevent the atypical ageing note taint in wines (due to 2-aminoacetophenone, AAP) is discussed with reference to: formation of AAP by yeasts, especially wild yeasts; chemical formation of AAP in the presence of SO2; the protective effect of ascorbic acid against AAP formation; lack of effect of ascorbic acid on AAP already present in wines; interference of ascorbic acid in testing for SO2 concn.; increased tendency to formation of sulfide taint in ascorbic acid treated wines; reduction of solubility of Cu in wines with added ascorbic acid; and reduction of oxidative shelf life of white wines.
Working with lees: key elements to wine maturing.
Delteil, D
Inst. Cooperatif du Vin, La Jasse de Maurin, 34 970 Lattes, Montpellier, France. Tel. +33 4 6707 0489. Fax +33 4 6707 0495. E-mail ddelteil@icv.fr
Australian-&-New-Zealand-Grapegrower-&-Winemaker. 2002; (461a): 104-107 ; 5 ref.
Utilization of lees in maturation of wines is discussed, with special reference to Mediterranean and Rhone Valley wines. Topics considered include: definition of heavy lees; heavy lees in red, rose and white wines; definition of light lees; potential problems associated with heavy and light lees, and their avoidance; the lack of any advantage of use of heavy lees in winemaking; and advantages of use of light lees in winemaking, as a source of polysaccharides, amino acids, nucleic acids and esters of importance for sensory quality of the wines.
Technological implications of the pH value in ageing and storage of red wines.
Vivas,-N; Vivas-de-Gaulejac,-N; Nonier,-M-F
CESAMO (Cent. d'Etude Structurale et d'Analyse des Molecules Organiques), Univ. Bordeaux I, Talence, France
Revue-des-Oenologues-et-des-Techniques-Vitivinicoles-et-Oenologiques. 2004; (110): 12-16
The importance of pH in ageing and storage of red wines is discussed with reference to: methods for measurement of pH; the trend towards increasing wine pH; effects of pH on properties of wines; effects on free SO2 concn.; effects on anthocyanins and colour of wines; effects on sensory impact of tannins; action in relation to oxidation/reduction status in wines; and effects on microbiological stability of wines.
Colloidal phenomena and the role of the lees in ageing of red wines: a new technological and methodological approach. II. Methods for ageing of wines in high capacity tanks.
Vivas,-N; Vivas-de-Gaulejac,-N; Nonier,-M-F; Nedjma,-M
Tonnellerie Demptos, Detache au CESAMO (Cent. d'Etude Structurale et d'Analyse des Molecules Organiques), Univ. Bordeaux I, 33405 Talence, France
Revue-Francaise-d'Oenologie. 2001; (190): 32-35 ; 2 ref.
Investigations were conducted on ageing of red wines on the lees in high capacity tanks. Potential problems with application of traditional style ageing under these conditions are considered. Investigations were conducted on use of yeast autolysates and yeast cell walls. Release of proteins and polysaccharides from the yeast preparations was assessed, and effects of these on the oxidative stability, phenols composition, colour and sensory quality of wines were determined. Results suggest that, even in large tanks, ageing in the presence of yeast components can improve oxidative stability, colour and sensory properties of wines. The role of added winemaking tannins is also considered.
Colloidal phenomena and the role of the lees in ageing of red wines: a new technological and methodological approach. I. Traditional methods of ageing of wines on the lees in barrels.
Vivas,-N; Vivas-de-Gaulejac,-N; Nonier,-M-F; Nedjma,-M
Tonnellerie Demptos, Detache au CESAMO (Cent. d'Etude Structurale et d'Analyse des Molecules Organiques), Univ. Bordeaux I, 33405 Talence, France
Revue-Francaise-d'Oenologie. 2001; (189): 33-38 ; 26 ref.
Studies were conducted on the role of the lees in traditional ageing of red wines in barrels or other small containers. Topics considered included; the relation between wine colour and development of oxidation aromas in the wine; the role of compounds released during yeast autolysis (especially proteins, polypeptides and amino acids) for oxidative stability of wines; the relation between contact with a source of soluble macromolecules and sensory properties of wines; improvement of 'rounded' sensory properties and decreased astringency of wines with increased concn. of yeast-derived polysaccharides; and technological implications (including the desirability of applying either malolactic fermentation or ageing on lees, but not both).
Estimation and quantification of wine phenolic compounds.
Vivas,-N; Vivas-de-Gaulejac,-N; Nonier,-M-F
Cent. d'Etude Structurale et d'Analyse des Molecules Organiques, Univ. Bordeaux I, 33405 Talence, France. E-mail n.vivas@cesamo.u-bordeaux.fr
Bulletin-de-l'O.I.V.. 2003; 76(865-866): 281-303 ; 20 ref.
Analysis of phenols in wines is discussed with reference to: structure of phenols present in grapes and wines (phenolic acids, stilbenes and flavonoids); methods for determination of total phenols in wines; methods for determination of proanthocyanidins; and methods for determination of anthocyanins.
Determination of age of Sherry wines by regression techniques using routine parameters and phenolic and volatile compounds.
Guillén D.; Palma M.; Natera R.; Romero R. García Barroso C
Dpto. Química Analítica. Fac. Ciencias. Univ. Cádiz. 11510 Puerto Real. email: dominico.guillen@uca.es
Journal of Agricultural and Food Chemistry, 2005, 53, 2412-2417
This paper describes a study of the possibility of obtaining regression models by means of partial least squares (PLS) and multiple linear regression (MLR) that would enable us to correlate a series of parameters, such as the concentration of short-chain organic acids, higher alcohols, and phenolic compounds with the age of vintage Sherry wines or “añadas”. The aim of this study is to characterize how these parameters evolve with aging. If this could be done, it would the be possible to guarantee the age of such wines using objective variables. A PLS regression modes was established that allows the age to be predicted with a mean deviation of 1.6 years with respect to the age of the wines. In the case of the MLR, a model with 6 variables was obtained that gives a mean deviation of 3.3 years in the predictions.
Extraction of volatile compounds in model wine from different oak woods: effect of SO2.
Ancin,-C; Garde,-T; Torrea,-D; Jimenez,-N
Dep. of Applied Chem., Univ. Publica de Navarra, Pamplona 31006, Spain. Tel. +34-948-168909. Fax +34-948-169606. E-mail ancin@unavarra.es
Food-Research-International. 2004; 37(4): 375-383 ; 24 ref.
Extraction of volatile compounds (uronic compounds, lactone compounds, phenolic aldehydes, phenolic alcohols) from different oak woods was investigated in synthetic wine with 2 different concn. of SO2 (50 and 30 mg/l). American oak (Quercus alba), from the Mississippi region, and French oak (Q. sessilis), from the Allier and Nevers regions, were macerated in the synthetic wine, and samples were taken for analysis on days 7, 17, 21, 28, 35, 49, 77, 91 and 105. SO2 was found to combine with vanillin and syringaldehyde, although its effect on these compounds was not detected at 30 mg/l. 5-Hydroxymethylfurfural and coniferaldehyde were detected, following several days maceration, in medium containing both 50 and 30 mg/l SO2. SO2 concn. had no influence on the extraction other compounds investigated. A larger difference in the quantity of extracted compounds was observed between the French oak from different regions rather than between French and American oak. It is therefore suggested that cooperage oak selection should be based on both oak species and geographical origin.
Is your wine really protected? Using molecular sulfur dioxide levels as the yardstick.
Howell,-G; Vallesi,-M
Vintessential Laboratories, Australia. Tel. 1300 30 2242. E-mail info@vintessential.com
Australian-&-New-Zealand-Grapegrower-&-Winemaker. 2004; (481): 54-56 ; 5 ref.
Monitoring molecular SO2 levels, rather than free SO2 levels, in wines is discussed. Topics considered include: aims of use of SO2 in wines; chemistry of SO2; dissociation of part of the free SO2 into sulfite and bisulfite ions; effects of pH on the proportion of free SO2 present as molecular SO2; levels of molecular SO2 needed for protection of wines; estimation of molecular SO2 concn. in wines; problems with errors in measurement of pH and SO2 in wines; and recommended levels for free SO2 in various wine types.
Alternatives to sulfur dioxide in enology. Part II. Red wines technology.
Comuzzo,-P; Tat,-L
Dipartimento di Sci. degli Alimenti, Univ. di Udine, 33100 Udine, Italy. E-mail comuzzo.piergiorgio.@spes.uniud.it
Industrie-delle-Bevande. 2003; 32(187): 457-462, 466 ; 12 ref.
As in the case of white wines (see FSTA 2004-04-Hj0989 for part I), there is currently no complete substitute for SO2 during red wine production, but the sulphites content can be reduced, particularly at the phenolic compound extraction stage, by use of tannins and other adjuvants. Techniques permitting the amount of SO2 used, primarily during maceration, to be reduced are reviewed.
Alternatives to sulfur dioxide in enology. Part I. White wines technology.
Comuzzo,-P; Tat,-L
Dipartimento di Sci. degli Alimenti, Univ. di Udine, 33100 Udine, Italy. E-mail comuzzo.piergiorgio@spes.uniud.it
Industrie-delle-Bevande. 2003; 32(187): 450-456 ; 11 ref.
Although SO2 has long been a basic component of the winemaking process, the recent trend has been towards reducing the amounts used in view of the compound's known toxicity. However, to date no substitute capable of fulfilling all the roles played by SO2, particularly its preservative, antioxidative and antioxidase activities, has been developed. Common oenological techniques designed to reduce the levels of SO2 required during white wine production are reviewed.
Protection of white winemaking grapes against oxidation by use of ascorbic acid. Experimental results.
Charrier,-F; Cottereau,-P
Unite de Nantes, ITV France, Chateau de la Fremoire, 44120 Vertau, France
Revue-Francaise-d'Oenologie. 2003; (201): 12-15
Comparative trials were conducted on use of SO2 alone (at 5 g/100 kg) or SO2 (5 g/100 kg) in combination with ascorbic acid (10 g/100 kg) for control of oxidation of white winemaking grapes or musts before fermentation. Trials were conducted on batches of Sauvignon Blanc, Muscat, Riesling, Melon Blanc and Grenache Blanc grapes. Results showed that the combined SO2/ascorbic acid treatment decreased browning of the grapes and musts, but adversely affected colour stability of the resulting wines. The SO2/ascorbic acid treatment gave higher total SO2 concn. than SO2 alone. However, the former had higher bound SO2 concn. It is concluded that use of ascorbic acid does not permit reduction of SO2 use level in wines. Other analytical parameters of the wines differed little between the 2 treatments. Use of SO2 increased aroma intensity (especially citrus fruit and tropical fruit notes) of wines made from aromatic cultivars such as Sauvignon Blanc and Riesling.
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