Grape Cultivars

Most of the anthocyanins acylated with caffeic acid have this cinnamyl moiety linked to a glucosyl position 6, as in gooseberries, some grape cultivars, ° " ° black carrots, red cabbage,red radishes," and sweet potatoes. Some anthocyanins isolated from species of potatoes have a caffeyl group located at position 4 of the rhamnosyl unit of the rutinose disaccharide. " ... 

Ruberto, G. et al.. Polyphenol constituents and antioxidant activity of grape pomace extracts from five Sicilian red grape cultivars. Food Chem., 100, 203, 2007. 

To detect adulteration of wine. Bums et al. (2002) found that the ratios of acetylated to p-coumaroylated conjugates of nine characteristic anthocyanins served as useful parameters to determine grape cultivars for a type of wine. Our laboratory utilized mid-infrared spectroscopy combined with multivariate analysis to provide spectral signature profiles that allowed the chemically based classification of antho-cyanin-containing fruits juices and produced distinctive and reproducible chemical fingerprints, making it possible to discriminate different juices. " This new application of ATR-FTIR to detect adulteration in anthocyanin-containing juices and foods may be an effective and efficient method for manufacturers to assure product quality and authenticity. 

A similar RP-HPLC method was developed and employed for the separation and quantitative determination of nine anthocyanins in red grape cultivars and red wines. Analysis... 

E. Revilla, E. Garcia-Beneytez, F. Cabello, G. Martin-Ortega and J.-M. Ryan, Value of high-performance liquid chromatographic analysis of anthocyanins in the differentiation of red grape cultivars and red wines made from them. J. Chromatogr.A 915 (2001) 53-60. 

Cantos, E., Espin, J., and Tomas-Barberan, F., Varietal differences among the polyphenol profiles of seven table grape cultivars studied by LC-DAD-MS-MS. J. Agric. Food Chem. 50, 5691, 2002. 

Karabourniotis, G., Bornman, J.F., and Liakoura, V., Different leaf surface characteristics of three grape cultivars affect leaf optical properties as measured with fibre optics possible implication in stress tolerance, Aust. J. Plant Physiol, 26, 47, 1999. 

By an improved solid-phase extraction procedure, 2-methyl-tetrahydro-furan-3-thiol 77 could be measured in wine at levels of 0.2 ng/L (01MI533, 08JC(A)9). This compound smells like strongly cooked meat, described as roasted meaty. From grape cultivars of the Vinho Verde region in Portugal 2-methyl-tetrahydrothiophen-3-one 78 was isolated (02ACA157). 

The other appellations of SGN wines are Coteaux du Layon, and Coteaux de l Aubance in the Loire valley, Anjou. Coteaux du Layon produces sweet wine only, and the single variety here is Chenin blanc, a neutral, acidic grape cultivar. It is extremely prone to noble rot. The required initial sugar content of the must is 294 g/1 for SGN wines (INAO, 2007). Two individual AOCs within this region are Bonnezeaux and Chaume. Most of these SGN wines are very sweet, in comparison with the other French styles. 

Desorption nano-electrospray (nano-DESI) has also been tested for qualitative analysis of anthocyanins in wine samples (Table 5.1 Method 5) (Hartmanova et ah, 2010). Acidifying of the samples and providing an acidic spray liquid (methanol/water 75 25 with 0.2% HCOOH) were essential for obtaining good quality spectra. From the nano-DESI-MS data, the ratio of two grape cultivars (Neronet and Rubinet) in a mixture could be determined. Detection of the main anthocyanins in slices of wine grapes, chokeberries, and elderberries or in a wine stain on cotton fabric was also possible (Hartmanova et al., 2010). 

Pozo-Bayon, M.A., Polo, M.C., Martfn-Alvarez, P.J., and Pueyo, E. (2004). Effect of vineyard yield on the composition of sparkling wines produced from the grape cultivar Parellada. Food Chem., 86, 413 19. 

Houtman, A. C., Du Plessis, C. S. (1986) The effect of grape cultivar and yeast strain on fermentation rate and concentration of volatile components in wine. South African Journal of Enology and Viticulture, 7, 14-20. 

Masa, A., Vilanova, M., Pomar, F. (2007). Varietal differences among the flavonoid profile of white grape cultivars studied by high performance liquid chromatography. /. Chromatogr. A 1164, 291-297. 

Red wines usually contain higher stilbene concentrations than ros6 or white wines. This depends on the more prolonged skin contact of the must during fermentation and the high phenolic content of red grape cultivars (Perrone et al. 2007). 

Pierce s disease, a bacterial disease common in the South, is spread by leafhoppers. Infected vines typically show scorched, dried leaves in midsummer, wilted dried fruit, and eventual death of the vine. There is no cure for this disease. Dig up infected plants and replant with disease-free stock. Muscadine grapes are resistant to Pierce s disease, as are the American grape cultivars Champanel , Herbemont , and Lenoir . 

Table 7.1 Protein composition of juice from different grape cultivars. TLP, thaumatin like proteins. (Reproduced from J. Agric. Food Chem., 2000, 48(5), 1637-1643, Pocock et al., with permission from the American Chemical Society).

Fukui, M., Okuda, T., Takayanagi, T. and Yokotsuka, K. (2002) Changes in amount of nitrogenous compounds from skins and seeds of four grape cultivars during extraction using juice or fermenting must-like model solutions,/. Wine Research, 13, 203-215. 

Yokotsuka, K. and Fukui, M. (2002) Changes in nitrogen compounds in berries of six grape cultivars during ripening over two years, Am. ]. Enol. Vitic., 53, 69-77. 

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