Colour and pigment composition of red wines obtained from co-maceration of Tempranillo and Graciano varieties

[EN] The Vitis vinifera L. cv Graciano is often used as an integral component of Rioja wines because it is considered to contribute significantly to the quality of Tempranillo based wines. The aim of this work was to determine the effect of the incorporation of the Graciano variety on the colour and pigment composition of Tempranillo based wine and to evaluate the possible differences between blending Tempranillo with Graciano varietal wine (W wine) in contrast to a wine obtained by mixing these two grape varieties in the prefermentative maceration step (M wine). Results indicated that pigment extraction and retention in M wine was higher than in Tempranillo (T) wine. Colour differences (DeltaE(ab)(*)) between wines at the end of the study (after 12 months in bottles) were detectable by the human eye (DeltaE(ab)(*) > or = 3) in all cases except for T and W. These wines have indistinguishable colours even when using analytical methods (DeltaE(ab)(*) < or = 1). Regarding hue h(ab), T and W presented higher values (more orange-red) than Graciano (G) and M (more blue-red). PCA allowed the colour and composition analytical data to be reduced to a small number of principal components that could separate successfully between T and G wines and between the different steps of the winemaking process

Statistical correlation between flavanolic composition, colour and sensorial parameters in grape seed during ripening

[EN] The aim of this work has been to determine the correlations between sensory analysis, colour and content of main flavanols present in seeds. For this, the flavanic composition of grape seeds with different degrees of maturity was analysed by HPLC–DAD-MS and the obtained results were correlated with CIELab colour parameters, perceived colour (C), hardness of the seed (HS), tannic intensity (TI) and astringency (A). Multiple linear regression analysis (MLR) with the variables showing significant correlations (p < 0.05) was also performed. Grape seeds undergo important decreases in the content of catechins and procyanidin oligomers during ripening. Epicatechin-(4-8)-epicatechin-3-O-gallate (B2G) and (−)-epicatechin-3-Ogallate (ECG) are the flavanolic compounds whose contents decrease most. The changes in the phenolic composition accompany changes in TI, A and HS. The total content of flavanols in the seed is not the only factor affecting these attributes, since samples containing higher contents in flavanols can exhibit less astringency and tannic intensity than others with lower ones. The qualitative profile of the seeds is, therefore, also responsible for the sensations elicited in the mouth. A and HS parameters are more affected by the presence of galloylated dimeric procyanidins in the molecule than TI. CIELab colour parameters of seeds have high correlation coefficients with many flavanolic compounds. ECG was the compound most related to these parameters

Color-copigmentation study by tristimulus colorimetry (CIELAB) in red wines obtained from Tempranillo and Graciano varieties

[EN] A study of the changes of copigmentation phenomenon in wines elaborated from different varieties has been undertaken. Colorimetric measurement of Tempranillo (T) and Graciano (G) monovarietal wines, and two 80:20 blend wines: M, (grape blending T and G, co-maceration) and W (wine blending T and G, co-vinification) was performed by spectrophotometry. Significant differences (p < 0.05) were found among the color of the wines. The Graciano cv. afforded somewhat darker and more colorful wines than the other wines. The color difference values, ΔE*ab suggested that co-vinification (W) led to wines being more similar to T than the co-maceration (M). The ΔE*ab[w − c] between untreated wines – whole wines, w – and the wines diluted to eliminate copigmentation – corrected wines, c – was 14.2 CIELAB units in the initial stages of winemaking and 6.7 in the final stages. M had a greater proportion of color due to copigmentation than the monovarietal wines. Evaluation of this parameter confirms the importance of copigmentation process into wine color during the early stages of the vinification. Also, through the full spectrum, quantitative data obtained allow a visual interpretation of the changes involved. In addition, with the aging in bottle, M wines had more stable color and more different color than W wines

Multivariate analysis of the polyphenol composition of Tempranillo and Graciano red wines

[EN] Vitis vinifera L. cv Graciano is often used as a blending partner of Tempranillo based wines because it is considered to contribute significantly to the quality. The aim of this study is to discriminate between Tempranillo and Graciano monovarietal wines, and those made by the incorporation of 20% of Graciano variety in two different stages (at the end of malolactic fermentation and mixing the two grape varieties in the pre-fermentative maceration stage) of the winemaking process of the Tempranillo variety. To achieve this, supervised and unsupervised pattern recognition tools were applied to the data obtained in the study of the detailed polyphenolic composition, colour and other oenological parameters (143 variables). Patterns related to stages in the winemaking and ageing process, different wines and vintages can be observed using principal component analyses. Furthermore, linear discriminant analysis has been applied in order to characterise the wine samples. From the 143 variables, flavan-3-ols have exerted a profound influence on wine differentiation

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Influencia de la variedad de uva y técnicas de vinificación en los procesos que intervienen en el color del vino tinto

[ES] Tesis doctoral sobre la influencia de la variedad de uva y técnicas de vinificación en los procesos que intervienen en el color del vino tinto.[EN] Doctoral thesis on the influence of grape variety and winemaking techniques in the processes involved in the color of red wine

Influence of oenological practices on the formation of biogenic amines in quality red wines

[EN]Changes in the contents of biogenic amines (histamine, putrescine, tyramine, cadaverine, agmatine, ethylamine, isobutylamine, phenyletilamine, isoamylamine, serotonine and tryptamine) were studied during the winemaking process of quality red wines, including an organic wine. The analytical method used was validated in terms of linearity, precision, coefficient of variation and recovery. The limits of detection and quantification of the amines were also calculated. The method involved pre-column automated derivatisation of the amines by treatment with o-phthalaldehyde, after which the derivatives formed were analysed by reverse-phase HPLC. Results showed that grapemust already contains biogenic amines and this content tends to increase throughout winemaking and maturation. The organic wine showed higher levels of biogenic amines than the non-organic wine. The fact that malolactic fermentation occurs spontaneously in organic wines, together with low levels of SO2 because of legal restrictions, could be responsible for the higher levels in biogenic amines found. For the non-organic wine, 2 oenological practices could increase the content in biogenic amines: the addition of press wine to the free run wine, and the treatment with yeast mannoproteins