Real-Time Detection of Volatiles Released During Meat Spoilage: a Case Study of Modified Atmosphere-Packaged Chicken Breast Fillets Inoculated with <Emphasis Type="Italic">Br. thermosphacta</Emphasis>

The microbial spoilage of meat is accompanied by the release of volatile organic compounds (VOCs), many of which are odorous. These compounds give spoiled meat its characteristic pungent, sour, sulphury odour that provides consumers with an indication that the meat is unpalatable. Characterising meat spoilage based on volatile markers is of interest to the food industry in view of developing food freshness indicators (FFIs) to maintain food quality and reduce food waste. Conventional analytical methods for detecting VOCs developing during food spoilage involve intermittent sampling that delivers only snapshots of the release processes and thereby only limited information on the kinetics of their production and release. Proton-transfer-reaction mass spectrometry (PTR-MS) is an on-line technique that enables the detection of VOCs in real-time, thereby offering the possibility to follow the release of VOCs with a high time resolution. An analytical method using PTR-MS was developed to enable the continuous detection of VOCs released from chicken breast fillets inoculated with Brochothrix thermosphacta and stored under modified atmosphere (30 % CO₂, 70 % O₂) at 4 °C for 1 week. The meat spoilage VOCs detected by PTR-MS displayed different temporal dynamics of production and release, depending on the extent of spoilage. This paper describes the development of an analytical set-up for real-time detection of volatile spoilage markers using PTR-MS. This case study using inoculated chicken breast fillets demonstrates the applicability of this method to characterise individual VOC release patterns, which is of potential utility in the development of FFIs for the consumer market.