Device for measuring the concentration of gas components and / or the vapor state of a gas mixture
A device for measuring the concentration of gas components and / or the vapor state from a gas mixture, using visually observable reaction zones for gas test tubes containing a substance reacting with the components to be detected, the change in the reaction zone can be ascertained by direct observation and / or by means of an optoelectronic scanning device. According to the invention, the reactive substance is accommodated in at least one channel 1 which is formed in a support 2 and the cross section in the reaction zone is less than 1 mm ** 2.
Typical flavour of Muscat d'Alexandrie wines is mainly due to volatile compounds coming from grapes of this variety. Therefore, the choice of grapes is crucial to obtain musts with a great aromatic potential, which will contribute to the final aroma of wines derived from those musts. In this study, three sampling techniques, liquid-liquid extraction (LLE), solid phase extraction (SPE) and simultaneous distillation-extraction (SDE), were compared for the analysis of volatile compounds in Muscat grape juice. Results showed that although the three techniques can be recommended for the quantitative analysis of volatile compounds from musts, LLE and SPE are better sample preparation techniques than SDE, mainly for determination of polar compounds such as acids or alcohols.