Tartaric acid concentrations 358

Crisp, S., Lewis, B. G. Wilson, A. D. (1979). Characterization of glass-ionomer cements. 5. Effect of tartaric acid concentration in the liquid component. Journal of Dentistry, 7, 304-5. 

Figure 18. Degree of sourness defined by tartaric acid concentration using the sensor output (a) and comparison between the sensor and humans (b).

FIG. 14 Effect of pH on the equilibrium tartaric acid dissociated fractions ( , O, [HT-]/ [T] , , [T2-]/[T] A, A, [H2T]/[T]) at two different ethanol volumetric fractions (0% v/v, closed symbols 18% v/v, open symbols), as estimated according to Berta (1993) and Usseglio-Tomasset and Bosia (1978) H2T, free tartaric acid concentration HT-, hydrogen tartrate concentration T2-, tartrate concentration T, overall tartaric acid concentration. 

The enological profile of must obtained from botrytized grapes is specific (Table 10.11). This juice is very rich in sugars but its acidity is similar to that of juice obtained from healthy grapes. The tartaric acid concentration is often even lower and the pH higher (from 3.5 to 4.0), attesting to the... 

When there is too much surplus malic acid in the initial must, part of the calcium carbonate added to the treated volume produces soluble calcium malate. At the time of final blending, the surplus calcium reacts with the tartaric acid of the untreated must. The deacidification thus occurs in two steps and acts essentially on the tartaric acid. The tartaric acid concentration therefore has to be adjusted in order to decrease malic acid concentrations substantially, by double salt formation (Usseglio-Tomasset and Bosia, 1992). This result can be obtained by using a mixture of calcium carbonate and calcium tartrate, also... 

The CIM disks, with low-volume monolith stationary phase, used in this application allowed the desired separation of the analyte under low-pressure conditions. The use of a mixing chamber and the precise control of timing allowed the inline preparation of the necessary high number of standard solution mixtures for the multivariate calibration. The mixing chamber also provided a homogeneous mixture before the transport to the detector. The large sampled volume (1 mL) allowed the recording of spectra without dispersion effects (D = 1). Samples were diluted and their pH was adjusted to 8.5 before injection. Nevertheless, validation for the tartaric acid concentration was not possible with the enzymatic kits used in this work. 

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