Wines inorganic constituents

In addition to their importance in the chemical reactions of alcoholic fermentation, some inorganic components have a significant effect on the stability of wines. Problems frequently are associated with excesses rather than deficiencies of certain inorganic constituents. Generally, excessive levels produce undesirable effects by altering the color, appearance, or taste of the wines (48). An excessive level of inorganic constituents in wines may arise from many sources such as the inherent content in musts, winery equipment, cellars, and vineyard materials. 

Since significant levels of other inorganic constituents usually occur from sources other than the fruit themselves, a discussion of these components is not included in this article. An excellent review of inorganic constituents of wines has been provided by Amerine (48). 

Fig. 2.10. Composition of a test sample of wine (schematic representation in the middle the size of each area symbolizes the relative amount of the respective component or sort of constituents) and of the measuring samples of inorganic and organic components, respectively (left and right diagrams)...

Sometimes it is necessary to apply two (or more) variants of sample preparation to get different measuring samples from only one test sample. This is the case if various problems have to be solved, e.g. determination of major- and ultra trace constituents, comparison of depth- and surface profiles, or analysis of inorganic and organic trace components in the same test sample. An example is shown in Fig. 2.10 where in a test sample of wine both inorganic and organic trace constituents have to be determined and, therefore, different measuring samples must be prepared. 

Capillary zone electrophoresis (CZE), with direct or indirect photometry and conductivity has become popular in wine analysis. Very little, or sometimes no sample preparation is needed and short analysis times are also apparent advantages of CE and CZE in the analysis of wine. Capillary isotachophoresis (ITP), with conductivity, thermometric, and UV absorption detection, is suitable for the separation of various anionic constituents (organic acids and inorganic anions), currently occurring in wines (Masar et al., 2001). 

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