STUDIES ON THE COSTITUENTS OF SWEET PEPPER (SENISE PEPPER PGI) SUBJECTED TO DIFFERENT DRYING TECHNIQUES

Summary

The work presented in this thesis, which is the first on the subject, was carried out at the Department of Chemistry, University of Milan under the supervision of Prof. Giovanna Speranza and Dr. Carlo Morelli within the project : “Drying, Juices and Jams of Organic Fruit and Vegetables: What happens to Desired and Non-Desired compounds?” (acronime “FaVOrDeNonDe”). The FaVorDeNonDe project, funded by the action of CORE Organic Plus (Coordination of European Transnational Research in Organic Food and Farming Systems)- Topic 4. Ensuring quality and safety of organic food along the processing chain, is coordinated by Dr. Roberto Lo Scalzo of CREA-IAA of Milan (Consiglio per la Ricerca in Agricoltura e l’Analisi dell’Economia Agraria - Unità di ricerca per i processi dell’industria agroalimentare) and, in addition to Italy, involves four other European countries such as Germany and Denmark.
At the origin of this project, there is an issue of great relevance in the agricultural industry: the quality of products derived from industrial transformation of fruit and vegetables, and in particular of some varieties which are used in small processing plants.
The work that has been done at the Chemistry Department is to study the relationship between the quality of raw material and the processed products of selected fruits and vegetables after being subjected to different sustainable processing techniques. Specific task is the identification of compounds with properties of taste (umami and kokumi compounds), through a fractionation guided by sensory analysis.
The analytical approach has been an initial fractionation by solvent at increasing polarity, with the subsequent TLC isolation of the main compounds interesting for the sensory taste of sweet bell pepper. The comparison with tomato, having a well-known pattern of tastants of the "umami" class, revealed that the main "umami" compound of tomato resulted absent in sweet bell pepper, and that the presence of new compounds have been monitored and, when fully purified, will be checked by NMR spectroscopy.