Automated analytical microsystem for the spectrophotometric monitoring of titratable acidity in white, rosé and red wines
Sández, Natàlia (Universitat Autònoma de Barcelona. Departament de Química)
Calvo-Lopez, Antonio (Universitat Autònoma de Barcelona. Departament de Química)
Vidigal, Susana S.M.P. (Universidade Católica Portuguesa)
Rangel, António O.S.S. (Universidade Católica Portuguesa)
Alonso Chamarro, Julián (Universitat Autònoma de Barcelona. Departament de Química)

Data:	2019
Resum:	The design, construction and evaluation of a low-cost cyclic olefin copolymer (COC)-based continuous flow microanalyzer with optical detection to determine the titratable acidity content of wine is here presented. The analysis method is based on the monitoring of the blue coloration decrease of a buffered bromothymol blue (BTB) solution in the presence of the acidic compounds of wine. The microanalyzer monolithically integrates the required microfluidic motifs as well as an optical flow cell where the measurements are performed by using a miniaturized and versatile photometric detection system. Fluid management is totally automated by the use of computer-controlled microvalves, permitting the automatic calibration of the system as well as the automatic sampling, including in-line dilution and analysis. The reduced size of the whole system along with its high simplicity and automation make it suitable for its application to the on-line monitoring of titratable acidity during wine-making processes. With the optimal conditions, a linear range up to 0. 50 g L-1 tartaric acid, a quantification limit (LOQ) of 0. 01 g L-1 and a detection limit (LOD) of 0. 004 g L-1 were obtained, covering the most common acidity content of musts and wines. A sampling rate up to 26 h-1 could be achieved, consuming less than 3 mL of inexpensive reagents per analysis and requiring no pretreatment of the sample. The microsystem has been successfully applied to the quantification of the titratable acidity content of several wine samples, being the results in excellent agreement with the ones obtained by the reference method.
Ajuts:	Agencia Estatal de Investigación CTQ2017-85011-R Agència de Gestió d'Ajuts Universitaris i de Recerca 2017/SGR-220
Drets:	Aquest document està subjecte a una llicència d'ús Creative Commons. Es permet la reproducció total o parcial, la distribució, i la comunicació pública de l'obra, sempre que no sigui amb finalitats comercials, i sempre que es reconegui l'autoria de l'obra original. No es permet la creació d'obres derivades.
Llengua:	Anglès
Document:	Article ; recerca ; Versió acceptada per publicar
Matèria:	Automation ; Cyclic olefin copolymer ; Lab on a chip ; Miniaturization ; Titratable acidity ; Wine acidity
Publicat a:	Analytica chimica acta, Vol. 1091 (December 2019) , p. 50-58, ISSN 1873-4324

DOI: 10.1016/j.aca.2019.09.052
PMID: 31679574

Postprint 28 p, 921.6 KB

El registre apareix a les col·leccions:
Articles > Articles de recerca
Articles > Articles publicats