Characterization of the dynamics of volatile organic compounds released by lactic acid bacteria on modified atmosphere packed beef by PTR-MS

Meat spoilage is a very complex process influenced by many yet not fully characterized factors. To improve the desired characterization especially knowledge about the generation of volatile organic compounds (VOCs) is of great importance since they indicate the freshness and thus the quality of meat. To achieve this, the formation and release of VOCs from modified atmosphere packaged beef was investigated at two different temperatures (4 and 10 degrees C) by online monitoring with proton-transfer-reaction mass spectrometry (PTR-MS) combined with microbial analysis at selected time points (days 0, 7, 10, 14 at 4 degrees C and days 0, 2, 4, 7 at 10 degrees C). By linking microbial analysis to PTR-MS data, the meat condition could be described in the early stages of spoilage by the occurrence of selective volatile organic compounds. In later stages of spoilage, the formation and release of VOCs differed more with time and temperature.