Development of a novel sample reuse approach to measure the impact of lean meat, bone and adipose tissue on the development of volatiles in vacuum-packed chilled lamb stored at 2 °C for 15 days.

The impact of different ratios of lean meat, adipose tissue (fat) and bone on the volatile organic compound (VOC) profile of vacuum-packed (VP) lamb stored at 2 °C for up to 15 days was investigated using two sampling approaches. VOC development in individual samples was followed over time using either a traditional sampling regime where replicate samples were sampled (single-use) at a given time or a novel approach where replicate samples were resampled (reuse) over time. VOCs present in the headspace of the packaged samples were detected using proton-transfer-reaction mass spectrometry (PTR-MS) with complementary solid phase micro-extraction gas chromatography-mass spectrometry (SPME-GC-MS) analysis on a subset of samples. Bacteria numbers were determined using standard microbiological methods. Meat packaged with 20% added adipose tissue contained slightly higher numbers of bacteria at the start of the trial with correspondingly higher VOC levels compared to lean meat alone. Storage time (as a proxy for microbial numbers) was the main driver for VOC production. Differences between the reuse and the single-use sample sets were minimal, suggesting that resampling of VP lamb samples may be a useful approach to study the development of low frequency spoilage patterns over time.