Grapes nitrogenous compounds

TABLE 6.4 Effect of Botrytis cinerea on some nitrogen compounds of the grape juice... 

Rapp, A. and Versini, G. (1991). Influence of nitrogen compounds in grapes on aroma compounds of wine. In proceedings of the international symposium on nitrogen in grapes and wine. Am. Soc. Enol. Vitic. 323,156-164. 

Dizy, M. Polo, M.C. (1996). Changes in concentration of nitrogenous compounds during fermentation of white grape musts at pilot plant scale. Food Sci. Technol. Ini, 2, 87-93. 

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. 

Sponholz, W.R. 1991. Nitrogen compounds in grapes, must, and wine. Proceedings of the International Symposium on Nitrogen in Grapes and Wine.]. Rantz (ed.). Davis, CA American Society for Enology and Viticulture, pp. 196-199. 

Nitrogen compounds may also be involved in the improvement of fermentation kinetics. Heating the crushed grapes increases not only the total nitrogen and amino compound concentrations, but also the consumption of nitrogen during fermentation. 

In a fermentor undergoing carbonic maceration, the grape berry is transformed by anaerobic metabolism reactions of its own cells. These reactions are independent of any yeast involvement and have been covered in the preceding section. Tissue degradation favors the maceration phenomena involved. Phenolic compounds, anthocyanins, nitrogen compounds and other components of the solid parts of the berry are diffused in the juice of the pulp. 

Grape and apple juices usually contain all of the trace nutrients required by Saccharomjces for fermentation of sugars to alcohol. Other fmit and diluted honey, as well as barley malt and rice extract, frequendy need additions of nitrogen, phosphoms, and potassium compounds, together with some autolyzed yeast to faciUtate the yeast growth necessary for fermentation. Stimulation oiy4.cetobacter frequendy requires the addition of autolyzed... 

The Scuppemong grape has a distinctive flavor characteristic. Kep-ner and Webb (47) analyzed the volatile essence of this grape and identified six alcohols, including 0-phenylethyl alcohol, five aldehydes, and five esters. No nitrogen or sulfur containing compounds were found which indicated the absence of methyl anthranilate. 

Hallinan, C. P., Saul, D. J., Jiranek, V. (1999) Differential utilisation of sulfur compounds for H2S liberation by nitrogen-starved wine yeasts. Australian Journal of Grape and Wine Research. 5, 82-90. 

Moreira, N., Mendes, F, Pereira, O., Guedes de Pinho, P, Hogg, X, Vasconcelos, I. (2002) Volatile sulphur compounds in wines related to yeast metabolism and nitrogen composition of grape musts. Analytica ChimicaActa, 458, 157-167. 

Rapp, A., Versini, G. (1996) Influence of nitrogen on compounds in grapes on aroma compounds in wines.Journal International des Sciences de la Vigne et du Vin, 51, 193-203. 

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