Repositori URV

Identifier: TDX:784

Handle: https://hdl.handle.net/20.500.11797/TDX784

Authors:
Martí Borras, Maria Pilar

Abstract:
Aroma is an important factor in quality control and quality assurance of foods, but in wines and in alcoholic beverages, this factor is possibly the most important. Wine aroma analysis is not an easy task to perform because aroma is composed of complex mixtures of hundreds of volatile compounds with different sensory and chemical properties and, moreover, the concentration levels of most of them are very low.The research work carried out in this thesis lay in the study and the characterisation of wine aroma by two very important techniques in this field: gas chromatography olfactometry (GCO) and electronic nose. GCO is a very useful technique in the study of wine aroma that makes it possible to identify, among all the volatile compounds, the odorous volatile compounds of the sample by using the human nose as chromatographic detector. The most important study carried out in this thesis by GCO was the development of a method for the characterisation of wine aroma that uses the solid-phase microextraction technique (SPME) as a sample pre-treatment technique. This method evaluates the aromatic intensity of the odorous compounds by a new approach of the aroma extract dilution analysis (AEDA) technique.Quality control of food has been carried out by sensory analysis since immemorial time. However, sensory analysis by a panel of experts is a costly process for industries because it requires trained people who can work for only relatively short periods of time. The purpose of the development of electronic noses was to achieve an instrument that could mimic the human sense of smell and provide rapid sensory information (e.g., differences and similarities among samples, presence of aromatic defects, etc.). Food analysis is probably the field in which the greatest number of applic