The influence of Cabernet Sauvignon grape maturity on the concentration and extraction of colour and phenolic compounds in wine (original) (raw)
Related papers
Journal of Agricultural and Food Chemistry, 2012
The aim of this paper was to study how maturity and maceration length affect color, phenolic compounds, polysaccharides, and sensorial quality of Cabernet Sauvignon and Tempranillo wines at three stages of grape ripening. Ripeness increased color extractability, phenolic compounds, and polysaccharide concentrations. Moreover, the proanthocyanidin mean degree of polymerization (mDP) and the percentage of prodelphinidins also increased with maturity, whereas the percentage of galloylation decreased. In general, wines from riper grapes contain higher proportions of skin proanthocyanidins. Color and anthocyanin concentration decreased when the maceration was longer, whereas polysaccharide and proanthocyanidin concentrations did the opposite. It was also detected that the mDP and the percentage of prodelphinidins decreased when the maceration was extended, whereas the percentage of galloylation increased. These data seem to indicate that proanthocyanidin extraction from seeds is clearly increased throughout the maceration time.
Relations between grape phenolic maturity and red wine phenolic composition
Italian Journal of Food Science
Phenolic maturity of red Piedmont grape varieties Nebbiolo and barbera was monitored during the grape harvest in 16 vineyards in 2000 and 2001. the study used the Glories' method which was modified to avoid some critical parts of the original protocol, mainly regarding the extraction solution used at pH 1. Experimental winemaking processes were performed on a part of the grapes from the vineyards being monitored. the analytical data revealed a correlation between the an-riAssuNto Nelle annate 2000 e 2001 è stato condotto un monitoraggio della maturità fenolica di uve rosse piemontesi Nebbiolo e barbera, che ha riguardato 16 vigneti. il lavoro ha permesso di mettere a punto modifiche al metodo per la valutazione della maturità fenolica proposto da Glories per ovviare ad alcune criticità dello stesso, segnatamente per quanto riguarda l'estrazione a pH 1. Parte delle uve dei vigneti sottoposti a monitoraggio sono state vinificate sperimentalmente. Lo studio dei dati analitici dei vini otte-366 Ital. J. Food Sci. n. 3, vol. 20 -2008 thocyanins and flavonoid indexes of grapes and color indexes of wines. the cell maturity index (EA%) is representative of how quickly anthocyanins can be extracted. Moreover, a correlation was found between the seed maturity index (Mp%) and the content of low molecular weight flavanols in the wine. in 2002-2004 this correlation was studied on Nebbiolo, barbera and Dolcetto grape varieties on an industrial scale. Winemaking carried out using different systems of maceration confirmed the experimental results.
Influence of the heterogeneity of grape phenolic maturity on wine composition and quality
Food Chemistry, 2011
Nowadays, consumers demand red wines with deep colour, soft tannins and fruit scents, but these wines can only be obtained from grapes with complete phenolic maturity. Diverse methods have been proposed for measuring phenolic maturity. However, all these methods only provide the average value and do not consider any possible heterogeneity. Throughout ripening, grapes were separated according to their density, which revealed the existence of a large heterogeneity. Grapes at harvest were also separated by density in three groups. The higher the density of the grapes the higher ethanol content, pH, colour intensity, total phenolic index and anthocyanin and proanthocyanidin concentrations, and the lower the titratable acidity and bitterness of the wines. When the grapes were denser the wines were also better balanced in flavour and mouthfeel sensation. These results suggest that grape heterogeneity may influence the final wine composition and quality and therefore it should be considered at harvest.
Journal of Agricultural and Food Chemistry, 2011
Changes in the phenolic composition, phenol extractability indices, and mechanical properties occur in grape berries during the ripening process, but the heterogeneity of the grapes harvested at different ripening stages affects the reliability of the results obtained. In this work, these changes were studied in Nebbiolo grapes harvested during five consecutive weeks and then separated according to three density classes. The changes observed in chemical and mechanical parameters through the ripening process are more related to berry density than harvest date. Therefore, the winemaker has to select the flotation density according to the objective quality properties of the wine to be elaborated. On the other hand, the stiffer grapes were associated with a higher accumulation of proanthocyanidins. The harder grapes provided the higher concentration and extractability of flavanols reactive to vanillin, whereas the thicker ones facilitated the extraction of proanthocyanidins.
Food Chemistry, 2011
Cabernet-Sauvignon and Merlot skin and seed extracts from Bordeaux grapes were investigated to determine both grape variety and vintage effect on phenolic composition. The total content of polyphenols and tannins in Merlot seeds was higher than that of Cabernet-Sauvignon allowing to discriminate the varieties. HPLC analyses underlined significant differences in the absolute concentration of proanthocyanidins amongst the two varieties and in their composition: mean degree of polymerisation (mDP) and percentage of galloylation of seed extracts were good indicators of grape variety. The vintage effect on the phenolic composition was confirmed for 2009 in comparison to previous vintages. Low values of mDP and concentrations of proanthocyanidins and anthocyanins were found in 2009 seeds and skins. The climatic conditions of 2009 (high rainfall before flowering followed by a strong hydric stress during berries development until ripening) let us hypothesise a lower activation of flavonoid pathway.
Effect of ripening stage of grapes on the low molecular weight phenolic compounds of red wines
European Food Research and Technology, 2005
Different red wines were elaborated to study the effect of the date of the grape harvest on the levels of individual low molecular weight phenolic compounds, which are chiefly responsible for the wine color. Two red grape varieties and two consecutive years were studied at three different harvesting stages of grapes, and the changes during the 18 months of wine aging (12 months in oak barrels and 6 months in the bottle) were also followed. The results showed that the wines made from grapes harvested 1 week later than the usual date generally had higher contents of some simple phenols, which can act as cofactors that can maintain the color intensity and violet tonalities in aged wines. Besides, these wines had lower levels of caftaric and coutaric acids, which are two of the main substrates for oxidation and browning processes.
International Journal of Food Science & Technology, 2010
The phenolic potential of the grapes of Tannat, Cabernet Sauvignon and Merlot produced in the south region of Uruguay was analysed in four years. The grapes of Tannat had the highest total phenolic richness (A280 = 80.0), total anthocyanin potential (ApH1 = 2540 mg L)1) and extractable anthocyanin potential (ApH3.2 = 1269 mg L)1), although there were important differences between the years. Representative winemaking of each vineyard was carried out. The differences verified in the grapes phenolic indexes were related to the colour and polyphenolic composition of the wines. The correlations between the phenolic indexes of the grapes and the colour and polyphenolic composition of the wines were very high. The estimation of the polyphenolic richness and the extractability of the anthocyanins of the grapes allow to improve the management of the winemaking and the prediction of the chromatic characteristics and the global polyphenolic composition of the wines.
International Journal of Food Science & Technology, 2017
The phenolic composition of red wines is complex and intimately involved in colour, taste, mouth-feel and aroma. There have been significant advances in knowledge of compounds with relatively simple structures, but understanding of those with more complex and probably diverse structures is challenging. A number of phenolic compounds may form temporary complexes with anthocyanins and/or be involved in reactions that lead to relatively stable coloured compounds. A wide range of phenolic compounds is implicated in the oral sensory attributes of red wines. Of particular importance are flavan-3-ols, including proanthocyanidins (PAs). The generally observed decline in the extractability of PAs during berry ripening is due to binding with cell wall material, which may occur within the developing berry and also from tissues brought into contact during processing. Studies have shown that exposure/reduced vigour results in an increasing proportion of skin PAs being extractable during wine making. Temperature and light influence anthocyanin with temperature probably being more important and the most sensitive stage being 1-3 weeks after v eraison. Skin PAs are extracted earlier than those from seeds during winemaking. Recent results suggest some rearrangement of skin and/or seed PAs occurs during vinification which involves the cleavage of large polymers or the aggregation of small ones. The polymeric material is particularly influential in wine astringency and is transformed by incorporation of anthocyanins into tannin-like compounds during wine-making and storage. Although some grape-derived phenolic compounds contribute to the aroma of red wines, likely of greater importance are the effects of nonvolatile phenolics on the volatility of a diverse range of aroma compounds. Advances in analytical techniques are likely to provide greater insights into the structures and conformations of phenolic polymers and the role of cell wall material in relation to phenolic extraction and reaction during vinification. In relation to aroma, much more research is required to reveal the details of the interactions involving phenolics with volatile compounds. It seems likely that the ability to influence the relative extraction and subsequent reaction of skin and seed phenolics is important in the production of full colour, aromatic and long-lived wines.
Analytica Chimica Acta, 2010
With the aim of determining the real predictive ability of three methods for measuring phenolic maturity (Glories, ITV and Cromoenos), representative grapes of Merlot, Cabernet sauvignon, Grenache and Tempranillo were harvested at three different ripening levels. The grapes were vinified by triplicate and were also used for phenolic maturity estimation. After that, color intensity, CIELAB coordinates, anthocyanins by spectrometry and HPLC and total phenolics were analysed in wines and also in the different extracts from the three extraction methods. Statistical analysis of data was carried out to determine the real performance of prediction of the different methods. Glories method predicted reasonably the color intensity, CIELAB coordinates and the concentration of anthocyanins and total phenolics in wine although it needs a lot of time and it requires working carefully. On the other hand, Cromoenos method predicted similarly or even better the color and phenolic composition of wine. This method also presents the advantage of being much faster and easier to apply. In contrast, although the ITV method provided reasonable results for anthocyanins and total phenolic compounds its color prediction was not adequate.
Grapes and Wines - Advances in Production, Processing, Analysis and Valorization
InTech eBooks, 2018
Phenolic compounds are a group of natural products that play an important role in the quality of wines. Most phenolic compounds present in wine are derived from those contained in grapes and extracted from skins, seeds, and pulp during the initial steps of winemaking. Among them, anthocyanins and flavonols are involved in the color of red wines as pigments or copigments and also as precursors of polymeric pigments after reaction with other phenols. Biosynthesis of those phenolics in grapes is regulated by different genes; thus, each grape genotype presents a characteristic phenolic fingerprint, which is modulated by different environmental conditions. In this chapter, the anthocyanins and flavonols composition of different genotypes of wild grapes preserved at El Encin Germplasm Bank has been examined in detail. Wild grapevines are a remarkable genetic resource that may be used in breeding programs to improve the phenolic composition of cultivated grapes and, hence, the quality of red wines.