Wine, acid-alcohol ratio

To apply this rule, the alcoholic strength (by volume) and the fixed acidity of the wine are determined. The latter, expressed as sulphuric acid, is increased by 07 (this corresponding with the maximum value of the volatile acidity in ordinary normal wines), and the value thus obtained divided by the alcoholic strength the quotient is the ratio sought. 

Wild apricot (Prunus armenica L.) grows naturally in hilly areas of northern India. It is highly acidic, fibrous, and low in TSS, and, thus, not utilized commercially. Preparation and evaluation of a vermouth from its fruit was undertaken (Abrol, 2009). Vermouths at different sugar (8,10, and 12 °Brix), alcohol (15%, 17%, and 19%), and spices levels (2.5% and 5%) were prepared. Those used in extract preparation are shown in Plate 8.1. The base wine was prepared from crushed fruit, adjusted to 24 °Brix, and diluted in a 1 2 ratio with water. To this mixture was added 200 ppm sulfur dioxide, 0.1% diammonium hydrogen phosphate (DAHP), and 0.5% pectinase enzyme. A 24-h active yeast culture initiated fermentation. The procedure is illustrated in Fig. 8.4. A maturation period of 6 months improved the quality of the vermouth. 

In Table 5.2 and Figure 5.5, data for a quantification comparison between the two techniques referred to some compounds important for the wine quality such as esters, alcohols and fatty acids relative to analysis of different wines, are reported. Figure 5.5 shows the straight line regressions between the concentrations measured after XAD-2 extraction and the ratios of GC-FID area of each compound to that of the internal standard applying the Kaltron method. 

The alcohol and acid in natural wines vary in an inverse ratio, in such a way that the volume percentage of alcohol added to the grams per liter of acid as sulfuric make a sum lying be-... 

Fermentation rarely stops spontaneously at the exact alcohol/sugar ratio desired. In some cases, it can go too far in other cases, it becomes excessively slow and the increase in volatile acidity is more significant than the decrease in the sugar concentration. At this point, the fermentation must be stopped. This operation generally consisted of adding sulfur dioxide to the wine. 

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