NON-VOLATILE TASTE COMPOUNDS ASSESSMENT OF COMMERCIAL ITALIAN TOMATO CULTIVARS BEFORE AND AFTER PROCESSING INTO DICED TOMATO AND TOMATO PUREE

Tomato is a fruit pertaining to Solanum lycopersicum species and is well known as a good source of nutrient and bioactive compounds. It contains in fact flavonoids, hydroxicinnamic acids and lycopene, whose amount depends on the cultivar, stage of ripeness, climatic conditions, light exposure, soil, irrigation and fertilization. All these molecules behave as antioxidants, that are important in prevention of cardiovascular disease and certain types of cancer. But tomato is also known for its unique taste which, in past years, was used to make flavorful foods. Unfortunately, in recent years there has been a gradual decline in tomato flavor, caused by intensive breeding practices for production traits, such as yield, disease resistance, sugar content, in the absence of selection for flavor. In addition post-harvest shipping and handling practices, selection of extended shelf-life cultivars contributed to the decline of flavor. For all these reasons, today many studies concern the identification of molecules responsible for tomato taste, aiming to characterize a good-tasting product from the molecular point of view. Since this typical taste is formed by the combination of volatile and non-volatile constituents, the aim of this work was to describe data about amino acids profile and their implication in tomato taste. Nine commercial Italian tomato cultivars were considered for this study in order to find possible differences among all the considered ones. Furthermore the same characterization was carried out on processed tomato products (diced tomatoes and tomato puree) to compare their amino acidic profiles with those of fresh matter and evaluate any changes occurring after processing. Besides the characterization of amino acids content, performed by UPLC/MS technique, a qualitative analysis (soluble solids, total solids, total acidity, pH, total sugar content, Hunter color, Bostwick consistency, lycopene content) was carried out on fresh and processed samples. The amino acids analysis, confirmed that glutamic acid (Glu), γ-aminobutyric acid (GABA) and aspartic acid (Asp) are the most representative amino acids of both fresh fruit and tomato products and they increase during process.