[Changes in chemical composition of tomatoes during processing]

The influences of processing conditions and composition on chemical changes during thermal processing of tomatoes were investigated. During the Cold and Hot Break process pectin is degraded to different extents. Due to the thermal impact at first cyclization of glutamine to pyroglutamic acid takes place. At higher dry weight contents and during drying processes Amadori compounds and browning can be detected. The reaction products formed during thermal processing can be analysed by amino acid analysis and-after proper derivatization-by capillary gas chromatography.