Artículos de revistas
CONDUCTIMETRIC AND SPECTROPHOTOMETRIC DETERMINATION OF THE VOLATILE ACIDITY OF WINES BY FLOW-INJECTION
Registration in:
Analyst. Royal Soc Chemistry, v. 117, n. 5, n. 917, n. 919, 1992.
0003-2654
WOS:A1992HU71100017
Author
BARROS, FG
TUBINO, M
Institutions
Abstract
Usual methods for the determination of the volatile acidity of wines are relatively slow, as about 40 min are necessary to perform one analysis. In this work, a method was developed which provides results in a much shorter time. About 60 analyses can be performed in 1 h. The conductimetric analysis consists of the injection of the wine sample into a de-ionized water stream which then flows past a poly(tetrafluoroethylene) membrane separator. The acetic acid diffuses through the membrane into another water stream that passes through a conductivity cell. The spectrophotometric method is similar. The acetic acid diffuses into a stream of Bromocresol Purple solution, at pH 7.0, which passes through a flow cell in a spectrophotometer set at 540 nm. For comparison, analyses were also carried out by the method of Jaulmes. 117 5 917 919