Monitoring of volatile production in cooked poultry products using selected ion flow tube-mass spectrometry
Abstract Cooked poultry products are nutritious and economically valuable products that are at risk of bacterial spoilage, which can be postponed by cooling and modified-atmosphere-packaging (MAP). In this study, a cooked chicken product was stored at three different temperature ranges (4–6 °C, 7–9 °C, and 11–13 °C) and volatile production was measured over time using selected ion flow tube-mass spectrometry (SIFT-MS). The identities of the volatiles formed were confirmed by headspace solid-phase microextraction coupled with gas chromatography time-of-flight mass spectrometry (HS-SPME-GC-TOF-MS) analysis. In total, 33 volatiles were proposed using the latter technique and their concentrations were calculated using product ion counts after assignment of these counts to specific volatiles. The results indicated that 1-octen-3-ol, 2,3-butanediol, acetoin, benzaldehyde, ethanol, methylbutanal, and methylbutanol may serve as biomarkers for bacterial growth and/or chemical degradation of cooked poultry products. In parallel, the bacterial loads of the product samples were determined on selective agar media. A total of 495 bacterial isolates was classified and identified by (GTG) 5 -PCR fingerprinting, followed by gene sequencing of representative cluster isolates. Carnobacterium divergens , Carnobacterium maltaromaticum , Rahnella aquatilis, and Serratia proteamaculans were the most commonly found species, besides minor contributions of Lactobacillus sakei and Hafnia alvei . Differences in volatile profiles could thus be ascribed to variations in bacterial loads and storage temperatures.